cephalic presentation at 4 months

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The way a baby is positioned in the uterus just before birth can have a big effect on labor and delivery. This positioning is called fetal presentation.

Babies twist, stretch and tumble quite a bit during pregnancy. Before labor starts, however, they usually come to rest in a way that allows them to be delivered through the birth canal headfirst. This position is called cephalic presentation. But there are other ways a baby may settle just before labor begins.

Following are some of the possible ways a baby may be positioned at the end of pregnancy.

Head down, face down

When a baby is head down, face down, the medical term for it is the cephalic occiput anterior position. This the most common position for a baby to be born in. With the face down and turned slightly to the side, the smallest part of the baby's head leads the way through the birth canal. It is the easiest way for a baby to be born.

Head down, face up

When a baby is head down, face up, the medical term for it is the cephalic occiput posterior position. In this position, it might be harder for a baby's head to go under the pubic bone during delivery. That can make labor take longer.

Most babies who begin labor in this position eventually turn to be face down. If that doesn't happen, and the second stage of labor is taking a long time, a member of the health care team may reach through the vagina to help the baby turn. This is called manual rotation.

In some cases, a baby can be born in the head-down, face-up position. Use of forceps or a vacuum device to help with delivery is more common when a baby is in this position than in the head-down, face-down position. In some cases, a C-section delivery may be needed.

Frank breech

When a baby's feet or buttocks are in place to come out first during birth, it's called a breech presentation. This happens in about 3% to 4% of babies close to the time of birth. The baby shown below is in a frank breech presentation. That's when the knees aren't bent, and the feet are close to the baby's head. This is the most common type of breech presentation.

If you are more than 36 weeks into your pregnancy and your baby is in a frank breech presentation, your health care professional may try to move the baby into a head-down position. This is done using a procedure called external cephalic version. It involves one or two members of the health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

If the procedure isn't successful, or if the baby moves back into a breech position, talk with a member of your health care team about the choices you have for delivery. Most babies in a frank breech position are born by planned C-section.

Complete and incomplete breech

A complete breech presentation, as shown below, is when the baby has both knees bent and both legs pulled close to the body. In an incomplete breech, one or both of the legs are not pulled close to the body, and one or both of the feet or knees are below the baby's buttocks. If a baby is in either of these positions, you might feel kicking in the lower part of your belly.

If you are more than 36 weeks into your pregnancy and your baby is in a complete or incomplete breech presentation, your health care professional may try to move the baby into a head-down position. This is done using a procedure called external cephalic version. It involves one or two members of the health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

If the procedure isn't successful, or if the baby moves back into a breech position, talk with a member of your health care team about the choices you have for delivery. Many babies in a complete or incomplete breech position are born by planned C-section.

When a baby is sideways — lying horizontal across the uterus, rather than vertical — it's called a transverse lie. In this position, the baby's back might be:

• Down, with the back facing the birth canal.
• Sideways, with one shoulder pointing toward the birth canal.
• Up, with the hands and feet facing the birth canal.

Although many babies are sideways early in pregnancy, few stay this way when labor begins.

If your baby is in a transverse lie during week 37 of your pregnancy, your health care professional may try to move the baby into a head-down position. This is done using a procedure called external cephalic version. External cephalic version involves one or two members of your health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

If the procedure isn't successful, or if the baby moves back into a transverse lie, talk with a member of your health care team about the choices you have for delivery. Many babies who are in a transverse lie are born by C-section.

If you're pregnant with twins and only the twin that's lower in the uterus is head down, as shown below, your health care provider may first deliver that baby vaginally.

Then, in some cases, your health care team may suggest delivering the second twin in the breech position. Or they may try to move the second twin into a head-down position. This is done using a procedure called external cephalic version. External cephalic version involves one or two members of the health care team putting pressure on your belly with their hands to get the baby to roll into a head-down position.

Your health care team may suggest delivery by C-section for the second twin if:

• An attempt to deliver the baby in the breech position is not successful.
• You do not want to try to have the baby delivered vaginally in the breech position.
• An attempt to move the baby into a head-down position is not successful.
• You do not want to try to move the baby to a head-down position.

In some cases, your health care team may advise that you have both twins delivered by C-section. That might happen if the lower twin is not head down, the second twin has low or high birth weight as compared to the first twin, or if preterm labor starts.

• Landon MB, et al., eds. Normal labor and delivery. In: Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed May 19, 2023.
• Holcroft Argani C, et al. Occiput posterior position. https://www.updtodate.com/contents/search. Accessed May 19, 2023.
• Frequently asked questions: If your baby is breech. American College of Obstetricians and Gynecologists https://www.acog.org/womens-health/faqs/if-your-baby-is-breech. Accessed May 22, 2023.
• Hofmeyr GJ. Overview of breech presentation. https://www.updtodate.com/contents/search. Accessed May 22, 2023.
• Strauss RA, et al. Transverse fetal lie. https://www.updtodate.com/contents/search. Accessed May 22, 2023.
• Chasen ST, et al. Twin pregnancy: Labor and delivery. https://www.updtodate.com/contents/search. Accessed May 22, 2023.
• Cohen R, et al. Is vaginal delivery of a breech second twin safe? A comparison between delivery of vertex and non-vertex second twins. The Journal of Maternal-Fetal & Neonatal Medicine. 2021; doi:10.1080/14767058.2021.2005569.
• Marnach ML (expert opinion). Mayo Clinic. May 31, 2023.

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What Is Cephalic Position?

The ideal fetal position for labor and delivery

• Why It's Best

Risks of Other Positions

• Determining Position
• Turning a Fetus

The cephalic position is when a fetus is head down when it is ready to enter the birth canal. This is one of a few variations of how a fetus can rest in the womb and is considered the ideal one for labor and delivery.

About 96% of babies are born in the cephalic position. Most settle into it between the 32nd and 36th weeks of pregnancy . Your healthcare provider will monitor the fetus's position during the last weeks of gestation to ensure this has happened by week 36.

If the fetus is not in the cephalic position at that point, the provider may try to turn it. If this doesn't work, some—but not all—practitioners will attempt to deliver vaginally, while others will recommend a Cesarean (C-section).

Getty Images

Why Is the Cephalic Position Best?

During labor, contractions dilate the cervix so the fetus has adequate room to come through the birth canal. The cephalic position is the easiest and safest way for the baby to pass through the birth canal.

If the fetus is in a noncephalic position, delivery becomes more challenging. Different fetal positions have a range of difficulties and varying risks.

A small percentage of babies present in noncephalic positions. This can pose risks both to the fetus and the mother, and make labor and delivery more challenging. It can also influence the way in which someone can deliver.

A fetus may actually find itself in any of these positions throughout pregnancy, as the move about the uterus. But as they grow, there will be less room to tumble around and they will settle into a final position.

It is at this point that noncephalic positions can pose significant risks.

Cephalic Posterior

A fetus may also present in an occiput or cephalic posterior position. This means they are positioned head down, but they are facing the abdomen instead of the back.

This position is also nicknamed "sunny-side up."

Presenting this way increases the chance of a painful and prolonged delivery.

There are three different types of breech fetal positioning:

• Frank breech: The legs are up with the feet near the head.
• Footling breech: One or both legs is lowered over the cervix.
• Complete breech: The fetus is bottom-first with knees bent.

A vaginal delivery is most times a safe way to deliver. But with breech positions, a vaginal delivery can be complicated.

When a baby is born in the breech position, the largest part—its head—is delivered last. This can result in them getting stuck in the birth canal (entrapped). This can cause injury or death.

The umbilical cord may also be damaged or slide down into the mouth of the womb, which can reduce or cut off the baby's oxygen supply.

Some providers are still comfortable performing a vaginal birth as long as the fetus is doing well. But breech is always a riskier delivery position compared with the cephalic position, and most cases require a C-section.

Likelihood of a Breech Baby

You are more likely to have a breech baby if you:

• Go into early labor before you're full term
• Have an abnormally shaped uterus, fibroids , or too much amniotic fluid
• Are pregnant with multiples
• Have placenta previa (when the placenta covers the cervix)

Transverse Lie

In transverse lie position, the fetus is presenting sideways across the uterus rather than vertically. They may be:

• Down, with the back facing the birth canal
• With one shoulder pointing toward the birth canal
• Up, with the hands and feet facing the birth canal

If a transverse lie is not corrected before labor, a C-section will be required. This is typically the case.

Determining Fetal Position

Your healthcare provider can determine if your baby is in cephalic presentation by performing a physical exam and ultrasound.

In the final weeks of pregnancy, your healthcare provider will feel your lower abdomen with their hands to assess the positioning of the baby. This includes where the head, back, and buttocks lie

If your healthcare provider senses that the fetus is in a breech position, they can use ultrasound to confirm their suspicion.

Turning a Fetus So They Are in Cephalic Position

External cephalic version (ECV) is a common, noninvasive procedure to turn a breech baby into cephalic position while it's still in the uterus.

This is only considered if a healthcare provider monitors presentation progress in the last trimester and notices that a fetus is maintaining a noncephalic position as your delivery date approaches.

External Cephalic Version (ECV)

ECV involves the healthcare provider applying pressure to your stomach to turn the fetus from the outside. They will attempt to rotate the head forward or backward and lift the buttocks in an upward position. Sometimes, they use ultrasound to help guide the process.

The best time to perform ECV is about 37 weeks of pregnancy. Afterward, the fetal heart rate will be monitored to make sure it’s within normal levels. You should be able to go home after having ECV done.

ECV has a 50% to 60% success rate. However, even if it does work, there is still a chance the fetus will return to the breech position before birth.

Natural Methods For Turning a Fetus

There are also natural methods that can help turn a fetus into cephalic position. There is no medical research that confirms their efficacy, however.

• Changing your position: Sometimes a fetus will move when you get into certain positions. Two specific movements that your provider may recommend include: Getting on your hands and knees and gently rocking back and forth. Another you could try is pushing your hips up in the air while laying on your back with your knees bent and feet flat on the floor (bridge pose).
• Playing stimulating sounds: Fetuses gravitate to sound. You may be successful at luring a fetus out of breech position by playing music or a recording of your voice near your lower abdomen.
• Chiropractic care: A chiropractor can try the Webster technique. This is a specific chiropractic analysis and adjustment which enables chiropractors to establish balance in the pregnant person's pelvis and reduce undue stress to the uterus and supporting ligaments.
• Acupuncture: This is a considerably safe way someone can try to turn a fetus. Some practitioners incorporate moxibustion—the burning of dried mugwort on certain areas of the body—because they believe it will enhance the chances of success.

A Word From Verywell

While most babies are born in cephalic position at delivery, this is not always the case. And while some fetuses can be turned, others may be more stubborn.

This may affect your labor and delivery wishes. Try to remember that having a healthy baby, and staying well yourself, are your ultimate priorities. That may mean diverting from your best laid plans.

Speaking to your healthcare provider about turning options and the safest route of delivery may help you adjust to this twist and feel better about how you will move ahead.

Glezerman M. Planned vaginal breech delivery: current status and the need to reconsider . Expert Rev Obstet Gynecol. 2012;7(2):159-166. doi:10.1586/eog.12.2

Cleveland Clinic. Fetal positions for birth .

MedlinePlus. Breech birth .

UT Southwestern Medical Center. Can you turn a breech baby around?

The American College of Obstetricians and Gynecologists. If your baby is breech .

Roecker CB. Breech repositioning unresponsive to Webster technique: coexistence of oligohydramnios .  Journal of Chiropractic Medicine . 2013;12(2):74-78. doi:10.1016/j.jcm.2013.06.003

By Cherie Berkley, MS Berkley is a journalist with a certification in global health from Johns Hopkins University and a master's degree in journalism.

Cephalic presentation

October 14, 2016

A cephalic presentation or head presentation or head-first presentation is a situation at childbirth where the fetus is in a longitudinal lie and the head enters the pelvis first; the most common form of cephalic presentation is the vertex presentation where the occiput is the leading part (the part that first enters the birth canal). All other presentations are abnormal (malpresentations) which are either more difficult to deliver or not deliverable by natural means.

The movement of the fetus to cephalic presentation is called head engagement. It occurs in the third trimester. In head engagement, the fetal head descends into the pelvic cavity so that only a small part (or none) of it can be felt abdominally. The perineum and cervix are further flattened and the head may be felt vaginally. Head engagement is known colloquially as the baby drop, and in natural medicine as the lightening because of the release of pressure on the upper abdomen and renewed ease in breathing. However, it severely reduces bladder capacity, increases pressure on the pelvic floor and the rectum, and the mother may experience the perpetual sensation that the fetus will “fall out” at any moment.

The vertex is the area of the vault bounded anteriorly by the anterior fontanelle and the coronal suture, posteriorly by the posterior fontanelle and the lambdoid suture and laterally by 2 lines passing through the parietal eminences.

In the vertex presentation the occiput typically is anterior and thus in an optimal position to negotiate the pelvic curve by extending the head. In an occiput posterior position, labor becomes prolonged and more operative interventions are deemed necessary. The prevalence of the persistent occiput posterior is given as 4.7 %

The vertex presentations are further classified according to the position of the occiput, it being right, left, or transverse, and anterior or posterior:

Left Occipito-Anterior (LOA), Left Occipito-Posterior (LOP), Left Occipito-Transverse (LOT); Right Occipito-Anterior (ROA), Right Occipito-Posterior (ROP), Right Occipito-Transverse (ROT);

By Mikael Häggström – Own work, Public Domain  

Cephalic presentation. (2016, September 17). In Wikipedia, The Free Encyclopedia . Retrieved 05:18, September 17, 2016, from https://en.wikipedia.org/w/index.php?title=Cephalic_presentation&oldid=739815165

Fetal Presentation, Position, and Lie (Including Breech Presentation)

• Variations in Fetal Position and Presentation |

During pregnancy, the fetus can be positioned in many different ways inside the mother's uterus. The fetus may be head up or down or facing the mother's back or front. At first, the fetus can move around easily or shift position as the mother moves. Toward the end of the pregnancy the fetus is larger, has less room to move, and stays in one position. How the fetus is positioned has an important effect on delivery and, for certain positions, a cesarean delivery is necessary. There are medical terms that describe precisely how the fetus is positioned, and identifying the fetal position helps doctors to anticipate potential difficulties during labor and delivery.

Presentation refers to the part of the fetus’s body that leads the way out through the birth canal (called the presenting part). Usually, the head leads the way, but sometimes the buttocks (breech presentation), shoulder, or face leads the way.

Position refers to whether the fetus is facing backward (occiput anterior) or forward (occiput posterior). The occiput is a bone at the back of the baby's head. Therefore, facing backward is called occiput anterior (facing the mother’s back and facing down when the mother lies on her back). Facing forward is called occiput posterior (facing toward the mother's pubic bone and facing up when the mother lies on her back).

Lie refers to the angle of the fetus in relation to the mother and the uterus. Up-and-down (with the baby's spine parallel to mother's spine, called longitudinal) is normal, but sometimes the lie is sideways (transverse) or at an angle (oblique).

For these aspects of fetal positioning, the combination that is the most common, safest, and easiest for the mother to deliver is the following:

Head first (called vertex or cephalic presentation)

Facing backward (occiput anterior position)

Spine parallel to mother's spine (longitudinal lie)

Neck bent forward with chin tucked

Arms folded across the chest

If the fetus is in a different position, lie, or presentation, labor may be more difficult, and a normal vaginal delivery may not be possible.

Variations in fetal presentation, position, or lie may occur when

The fetus is too large for the mother's pelvis (fetopelvic disproportion).

The uterus is abnormally shaped or contains growths such as fibroids .

The fetus has a birth defect .

There is more than one fetus (multiple gestation).

Position and Presentation of the Fetus

Variations in Fetal Position and Presentation

Some variations in position and presentation that make delivery difficult occur frequently.

Occiput posterior position

In occiput posterior position (sometimes called sunny-side up), the fetus is head first (vertex presentation) but is facing forward (toward the mother's pubic bone—that is, facing up when the mother lies on her back). This is a very common position that is not abnormal, but it makes delivery more difficult than when the fetus is in the occiput anterior position (facing toward the mother's spine—that is facing down when the mother lies on her back).

When a fetus faces up, the neck is often straightened rather than bent,which requires more room for the head to pass through the birth canal. Delivery assisted by a vacuum device or forceps or cesarean delivery may be necessary.

Breech presentation

In breech presentation, the baby's buttocks or sometimes the feet are positioned to deliver first (before the head).

When delivered vaginally, babies that present buttocks first are more at risk of injury or even death than those that present head first.

The reason for the risks to babies in breech presentation is that the baby's hips and buttocks are not as wide as the head. Therefore, when the hips and buttocks pass through the cervix first, the passageway may not be wide enough for the head to pass through. In addition, when the head follows the buttocks, the neck may be bent slightly backwards. The neck being bent backward increases the width required for delivery as compared to when the head is angled forward with the chin tucked, which is the position that is easiest for delivery. Thus, the baby’s body may be delivered and then the head may get caught and not be able to pass through the birth canal. When the baby’s head is caught, this puts pressure on the umbilical cord in the birth canal, so that very little oxygen can reach the baby. Brain damage due to lack of oxygen is more common among breech babies than among those presenting head first.

In a first delivery, these problems may occur more frequently because a woman’s tissues have not been stretched by previous deliveries. Because of risk of injury or even death to the baby, cesarean delivery is preferred when the fetus is in breech presentation, unless the doctor is very experienced with and skilled at delivering breech babies or there is not an adequate facility or equipment to safely perform a cesarean delivery.

Breech presentation is more likely to occur in the following circumstances:

Labor starts too soon (preterm labor).

The uterus is abnormally shaped or contains abnormal growths such as fibroids .

Other presentations

In face presentation, the baby's neck arches back so that the face presents first rather than the top of the head.

In brow presentation, the neck is moderately arched so that the brow presents first.

Usually, fetuses do not stay in a face or brow presentation. These presentations often change to a vertex (top of the head) presentation before or during labor. If they do not, a cesarean delivery is usually recommended.

In transverse lie, the fetus lies horizontally across the birth canal and presents shoulder first. A cesarean delivery is done, unless the fetus is the second in a set of twins. In such a case, the fetus may be turned to be delivered through the vagina.

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Management of Labour and Delivery – Questions

Rekha Wuntakal, Madhavi Kalidindi, Tony Hollingworth in Get Through , 2014

For each clinical scenario below, choose the single most appropriate stage of labour from the above list of options. Each option may be used once, more than once or not at all. A 30-year-old para 3 woman was admitted at term with regular uterine activity at 5 cm cervical dilatation and 4 hours later she delivered a female neonate with APGARs 9, 10, 10 at 1, 5 and 10 minutes. Syntometrine injection was given immediately after delivery and placenta with membranes was delivered completely 20 minutes after the delivery of the baby by continuous cord traction.A 23-year-old para 3 woman was admitted after spontaneous rupture of membranes at 39 weeks’ gestation. She is contracting 4 in 10 minutes and pushing involuntarily. On vaginal examination the cervix was fully dilated, vertex was 2 cm below the spines in direct occipito-anterior position with minimal caput and moulding.A 30-year-old nulliparous woman was admitted at term with uterine contractions once in every 5 minutes. On examination, the fetus is in cephalic presentation with two fifths palpable per abdomen. The cervix is central, soft, fully effaced and 2 cm dilated with intact membranes.

Biometric Measurements and Normal Growth Parameters in a Child

Nirmal Raj Gopinathan in Clinical Orthopedic Examination of a Child , 2021

In cephalic presentation, the intra-uterine fetal position is of universal flexion, which is carried by the child to the immediate post-partum period. The hips and knees are flexed. The lower legs are internally rotated. The feet are further internally rotated with respect to the lower legs. At times there is an external rotational contracture of the hip that tends to mask the true femoral rotational profile. The anatomy of the lower limbs changes significantly as the child grows. This is primarily in response to the development of motor abilities and the ability of the child to crawl, cruise, stand, walk, and finally run. These changes are seen right from the hip joints, the femoral neck, knees, and tibia to the feet.

DRCOG MCQs for Circuit A Questions

Una F. Coales in DRCOG: Practice MCQs and OSCEs: How to Pass First Time three Complete MCQ Practice Exams (180 MCQs) Three Complete OSCE Practice Papers (60 Questions) Detailed Answers and Tips , 2020

External cephalic version: Used to convert a breech presentation to cephalic presentation.Not contraindicated if there is a prior Caesarean section scar.Can cause premature labour.Contraindicated in hypertension.Can be performed after 33 weeks' gestation in a rhesus-negative mother.

Complex maternal congenital anomalies – a rare presentation and delivery through a supra-umbilical abdominal incision

Published in Journal of Obstetrics and Gynaecology , 2018

Samantha Bonner, Yara Mohammed

She had a spontaneous conception and booked at 9 weeks of gestation under consultant-led care. A scan confirmed the pregnancy was in the right uterus. She had no other significant medical history but did suffer from recurrent urinary tract infections and hence was on low-dose antibiotic prophylaxis. There was no sonographic evidence of hydronephrosis. Her body mass index (BMI) was 18 at the time of booking. Combined screening was low risk and she had a normal 20 week anomaly scan. She had serial growth scans which demonstrated a normal growth trajectory on a customised chart. The baby was consistently a cephalic presentation. She had multidisciplinary antenatal care, including specialist urologists, general surgeons, obstetricians and anaesthetists. An antenatal MRI scan had shown extensive adhesions over the lower segment of the uterus. She was extensively counselled regarding the mode of delivery and this was scheduled at 37 weeks of gestation to avoid the potential of spontaneous labour and an emergency Caesarean section.

Utilization of epidural volume extension technique for external cephalic version

Published in Baylor University Medical Center Proceedings , 2021

Hanna Hussey, James Damron, Mark F. Powell, Michelle Tubinis

Repeat ultrasound demonstrated breech presentation, normal amniotic fluid volume, and fetal head toward the maternal left abdomen. After 0.25 mg of intramuscular terbutaline injection, a forward roll was initiated by applying pressure from behind the fetal head toward the maternal left. Continuous progress was made and bedside ultrasound showed cephalic presentation. Immediately after successful ECV, the fetal heart rate was 70 beats/min but returned to baseline with conservative measures. Motor blockade regressed after approximately 1.5 hours. After 4 hours of fetal heart rate monitoring and tocometry, the patient was deemed stable for discharge. Follow-up discussion with the patient via phone call on postprocedure day 1 confirmed that she was not experiencing pain or concerning symptoms for neuraxial complications. She returned to the labor and delivery unit at 40 weeks’ gestation for elective induction of labor and had a successful vaginal delivery.

Antenatal scoring system in predicting the success of planned vaginal birth following one previous caesarean section

Aida Kalok, Shahril A. Zabil, Muhammad Abdul Jamil, Pei Shan Lim, Mohamad Nasir Shafiee, Nirmala Kampan, Shamsul Azhar Shah, Nor Azlin Mohamed Ismail

The inclusion criteria were pregnant women at 36 weeks of gestation or more with singleton foetus in cephalic presentation, who agreed for trial of vaginal delivery after one lower segment caesarean section. We excluded women with contraindication for vaginal birth, or who declined trial of vaginal delivery from this study. Previous antenatal history was noted and recorded during the 36-week assessment, including year and indication for previous caesarean section. Recurrent indications involved were cephalopelvic disproportion and obstructed labour. While non-recurrent indications were foetal distress and malpresentation. Past operative notes were checked for any operative complications such as extended uterine tear, organ injury and post-partum haemorrhage. Information regarding current pregnancy including pre-existing medical disorder was recorded. Estimated foetal weight based on ultrasound scan at 36 weeks of gestation was used in this study.

Related Knowledge Centers

• Breech Birth
• Occipital Bone
• Pelvic Cavity
• Presentation
• Shoulder Presentation

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Your baby in the birth canal

During labor and delivery, your baby must pass through your pelvic bones to reach the vaginal opening. The goal is to find the easiest way out. Certain body positions give the baby a smaller shape, which makes it easier for your baby to get through this tight passage.

The best position for the baby to pass through the pelvis is with the head down and the body facing toward the mother's back. This position is called occiput anterior.

Information

Certain terms are used to describe your baby's position and movement through the birth canal.

FETAL STATION

Fetal station refers to where the presenting part is in your pelvis.

• The presenting part. The presenting part is the part of the baby that leads the way through the birth canal. Most often, it is the baby's head, but it can be a shoulder, the buttocks, or the feet.
• Ischial spines. These are bone points on the mother's pelvis. Normally the ischial spines are the narrowest part of the pelvis.
• 0 station. This is when the baby's head is even with the ischial spines. The baby is said to be "engaged" when the largest part of the head has entered the pelvis.
• If the presenting part lies above the ischial spines, the station is reported as a negative number from -1 to -5.

In first-time moms, the baby's head may engage by 36 weeks into the pregnancy. However, engagement may happen later in the pregnancy, or even during labor.

This refers to how the baby's spine lines up with the mother's spine. Your baby's spine is between their head and tailbone.

Your baby will most often settle into a position in the pelvis before labor begins.

• If your baby's spine runs in the same direction (parallel) as your spine, the baby is said to be in a longitudinal lie. Nearly all babies are in a longitudinal lie.
• If the baby is sideways (at a 90-degree angle to your spine), the baby is said to be in a transverse lie.

FETAL ATTITUDE

The fetal attitude describes the position of the parts of your baby's body.

The normal fetal attitude is commonly called the fetal position.

• The head is tucked down to the chest.
• The arms and legs are drawn in towards the center of the chest.

Abnormal fetal attitudes include a head that is tilted back, so the brow or the face presents first. Other body parts may be positioned behind the back. When this happens, the presenting part will be larger as it passes through the pelvis. This makes delivery more difficult.

DELIVERY PRESENTATION

Delivery presentation describes the way the baby is positioned to come down the birth canal for delivery.

The best position for your baby inside your uterus at the time of delivery is head down. This is called cephalic presentation.

• This position makes it easier and safer for your baby to pass through the birth canal. Cephalic presentation occurs in about 97% of deliveries.
• There are different types of cephalic presentation, which depend on the position of the baby's limbs and head (fetal attitude).

If your baby is in any position other than head down, your doctor may recommend a cesarean delivery.

Breech presentation is when the baby's bottom is down. Breech presentation occurs about 3% of the time. There are a few types of breech:

• A complete breech is when the buttocks present first and both the hips and knees are flexed.
• A frank breech is when the hips are flexed so the legs are straight and completely drawn up toward the chest.
• Other breech positions occur when either the feet or knees present first.

The shoulder, arm, or trunk may present first if the fetus is in a transverse lie. This type of presentation occurs less than 1% of the time. Transverse lie is more common when you deliver before your due date, or have twins or triplets.

CARDINAL MOVEMENTS OF LABOR

As your baby passes through the birth canal, the baby's head will change positions. These changes are needed for your baby to fit and move through your pelvis. These movements of your baby's head are called cardinal movements of labor.

• This is when the widest part of your baby's head has entered the pelvis.
• Engagement tells your health care provider that your pelvis is large enough to allow the baby's head to move down (descend).
• This is when your baby's head moves down (descends) further through your pelvis.
• Most often, descent occurs during labor, either as the cervix dilates or after you begin pushing.
• During descent, the baby's head is flexed down so that the chin touches the chest.
• With the chin tucked, it is easier for the baby's head to pass through the pelvis.

Internal Rotation

• As your baby's head descends further, the head will most often rotate so the back of the head is just below your pubic bone. This helps the head fit the shape of your pelvis.
• Usually, the baby will be face down toward your spine.
• Sometimes, the baby will rotate so it faces up toward the pubic bone.
• As your baby's head rotates, extends, or flexes during labor, the body will stay in position with one shoulder down toward your spine and one shoulder up toward your belly.
• As your baby reaches the opening of the vagina, usually the back of the head is in contact with your pubic bone.
• At this point, the birth canal curves upward, and the baby's head must extend back. It rotates under and around the pubic bone.

External Rotation

• As the baby's head is delivered, it will rotate a quarter turn to be in line with the body.
• After the head is delivered, the top shoulder is delivered under the pubic bone.
• After the shoulder, the rest of the body is usually delivered without a problem.

Alternative Names

Shoulder presentation; Malpresentations; Breech birth; Cephalic presentation; Fetal lie; Fetal attitude; Fetal descent; Fetal station; Cardinal movements; Labor-birth canal; Delivery-birth canal

Barth WH. Malpresentations and malposition. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies . 8th ed. Philadelphia, PA: Elsevier; 2021:chap 17.

Kilpatrick SJ, Garrison E, Fairbrother E. Normal labor and delivery. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies . 8th ed. Philadelphia, PA: Elsevier; 2021:chap 11.

Review Date 11/10/2022

Updated by: John D. Jacobson, MD, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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Presentation and position of baby through pregnancy and at birth

9-minute read

If you are concerned about your baby’s movements, contact your doctor or midwife for advice immediately.

• If you baby is in a breech presentation, your doctor may recommend trying a technique called an external cephalic version to try and move your baby while they are still in the uterus for an easier birth.

What does presentation and position mean?

Presentation refers to the part of your baby’s body that is facing downwards in the direction of the birth canal.

Position refers to where your baby’s occiput (the bottom part of the back of their head) is in relation to your body.

If your baby is in a breech presentation , then position refers to where your baby’s sacrum (lower back) is in relation to your body.

People — including medical professionals — sometimes use these terms incorrectly. Sometimes when speaking about babies in breech presentation, the word ‘position’ will be used to refer to their presentation. For example, you may read information or hear people say ‘breech position’ instead of ‘breech presentation’.

What are the different types of presentation my baby could be in during pregnancy and birth?

Most babies present headfirst, also known as cephalic presentation. Most babies that are headfirst will be vertex presentation. This means that the crown of their head sits at the opening of your birth canal.

In rare cases, your baby can be headfirst but in face or brow presentation, which may not be suitable for vaginal birth.

If your baby is in a breech presentation, their feet or bottom will be closest to your birth canal. The 3 most common types of breech presentation are:

• frank or extended breech — where your baby’s legs are straight up in front of their body, with their feet up near their face
• complete or flexed breech — where your baby is in a sitting position with their legs crossed in front of their body and their feet near their bottom
• footling breech — where one or both of your baby’s feet are hanging below their bottom, so the foot or feet are coming first

Read more on breech presentation .

What are the different positions my baby could be in during pregnancy and birth?

If your baby is headfirst, the 3 main types of presentation are:

• anterior – when the back of your baby’s head is at the front of your belly
• lateral – when the back of your baby’s head is facing your side
• posterior – when the back of your baby’s head is towards your back

How will I know what presentation and position my baby is in?

Your doctor or midwife can usually work out your baby’s presentation by feeling your abdomen. They may also double check it with a portable ultrasound. Your baby’s presentation is usually checked around 36 weeks .

Your doctor or midwife will also confirm your baby’s head position in labour by examining your belly and using an ultrasound , and they may also do a vaginal examination . During the vaginal examination they are feeling for certain ridges on your baby’s head called sutures and fontanelles that help them work out which way your baby is positioned.

What is the ideal presentation and position for baby to be in for a vaginal birth?

For a vaginal birth, your baby will ideally be headfirst with the back of their head at the front of your belly, also known as being in the anterior position. This position is best for labour and birth since it means that the smallest part of your baby’s head goes down the birth canal first.

When does a baby usually get in the ideal presentation and position for birth?

Your baby will usually be in a headfirst position by 37 weeks of pregnancy. Around 3 in every 100 babies will be in breech presentation after 37 weeks.

Your baby’s position can change with your contractions during labour as they move down the birth canal, so their exact position can change during labour.

What are my options if baby isn't in the ideal presentation or position for a vaginal birth?

If your baby is in a breech presentation, your doctor may recommend a technique called an external cephalic version (ECV) to try and move your baby while they are still in the uterus . An ECV involves your doctor using their hands to apply pressure on your belly and help turn your baby to a headfirst position. It has a 1 in 2 chance of success and is a safe option in most pregnancies.

There is no evidence to show that alternative therapies, such as exercises, acupuncture or chiropractic treatments, help your baby change from a breech presentation to headfirst.

If your baby remains breech, your doctor may discuss having a breech vaginal birth. Not all doctors and hospitals offer this option. They may also suggest you birth your baby with a planned caesarean section .

If your baby’s presentation is headfirst but the position of your baby’s head is not ideal for labour, it can lead to a longer labour, and potential complications . The position of your baby’s head will often change as your labour progresses. If it doesn’t, sometimes you can still give birth without assistance, or you may need your doctor to help turn your baby’s head or help your birth with a vacuum or forceps .

Any procedure or decision for a type of birth will only go ahead with your consent . You will be able to discuss all the options with your doctor, and based on your preferences for yourself and your baby’s safety, make a decision together .

Resources and support

The Royal Australian and New Zealand College of Obstetrics and Gynaecology has a factsheet about the options available to you if your baby is in a breech presentation at the end of your pregnancy .

Mercy Perinatal has information on external cephalic version (ECV) safety and benefits if your baby is in a breech presentation at the end of your pregnancy.

The Women’s Hospital has information about the different presentations and positions your baby could be in, and how it can affect your birthing experience.

Speak to a maternal child health nurse

Call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436 or video call . Available 7am to midnight (AET), 7 days a week.

Learn more here about the development and quality assurance of healthdirect content .

Last reviewed: October 2023

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External cephalic version (ecv), malpresentation, breech pregnancy, search our site for.

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In preparation for a safe birth, your health team will need to turn your baby if it is in a bottom first ‘breech’ position.

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Breech Presentation at the End of your Pregnancy

Breech presentation occurs when your baby is lying bottom first or feet first in the uterus (womb) rather than the usual head first position. In early pregnancy, a breech position is very common.

Read more on RANZCOG - Royal Australian and New Zealand College of Obstetricians and Gynaecologists website

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Read more on Pregnancy, Birth & Baby website

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ECV is a procedure to try to move your baby from a breech position to a head-down position. This is performed by a trained doctor.

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Planned or elective caesarean

There are important things to consider if you are having a planned or elective caesarean such as what happens during and after the procedure.

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• Prenatal Care

Fetal Cephalic Presentation During Pregnancy

What Is Cephalic Position?

Types of cephalic position, benefits of cephalic presentation, risks of cephalic position, what are some other positions and their associated risks, when does a foetus get into the cephalic position, how do you know if baby is in cephalic position, how to turn a breech baby into cephalic position, natural ways to turn a baby into cephalic position.

If your baby is moving around in the womb, it’s a good sign as it tells you that your baby is developing just fine. A baby starts moving around in the belly at around 14 weeks. And their first movements are usually called ‘ quickening’ or ‘fluttering’.

A baby can settle into many different positions throughout the pregnancy, and it’s alright. But it is only when you have reached your third and final trimester that the position of your baby in your womb will matter the most. The position that your baby takes at the end of the gestation period will most likely be how your baby will make its appearance in the world. Out of all the different positions that your baby can settle into, the cephalic position at 36 weeks is considered the best position. Read on to learn more about fetal cephalic presentation.

When it comes to cephalic presentation meaning, the following can be considered. A baby is in the cephalic position when he is in a head-down position. This is the best position for them to come out in. In case of a ‘cephalic presentation’, the chances of a smooth delivery are higher. This position is where your baby’s head has positioned itself close to the birth canal, and the feet and bottom are up. This is the best position for your baby to be in for safe and healthy delivery.

Your doctor will begin to keep an eye on the position of your baby at around 34 weeks to 36 weeks . The closer you get to your due date, the more important it is that your baby takes the cephalic position. If your baby is not in this position, your doctor will try gentle nudges to get your baby in the right position.

Though it is pretty straightforward, the cephalic position actually has two types, which are explained below:

1. Cephalic Occiput Anterior

Most babies settle in this position. Out of all the babies who settle in the cephalic position, 95% of them will settle this way. This is when a baby is in the head-down position but is facing the mother’s back. This is the preferred position as the baby is able to slide out more easily than in any other position.

2. Cephalic Occiput Posterior

In this position, the baby is in the head-down position but the baby’s face is turned towards the mother’s belly. This type of cephalic presentation is not the best position for delivery as the baby’s head could get stuck owing to its wide position. Almost 5% of the babies in cephalic presentation settle into this position. Babies who come out in this position are said to come out ‘sunny side up’.

Cephalic presentation, where the baby’s head is positioned down towards the birth canal, is the most common and optimal fetal presentation for childbirth. This positioning facilitates a smoother delivery process for both the mother and the baby. Here are several benefits associated with cephalic presentation:

1. Reduced risk of complications

Cephalic presentation decreases the likelihood of complications during labor and delivery , such as umbilical cord prolapse or shoulder dystocia, which can occur with other presentations.

2. Easier vaginal delivery

With the baby’s head positioned first, vaginal delivery is generally easier and less complicated compared to other presentations, resulting in a smoother labor process for the mother.

3. Lower risk of birth injuries

Cephalic presentation reduces the risk of birth injuries to the baby, such as head trauma or brachial plexus injuries, which may occur with other presentations, particularly breech or transverse positions.

4. Faster progression of labor

Babies in cephalic presentation often help to stimulate labor progression more effectively through their positioning, potentially shortening the duration of labor and reducing the need for medical interventions.

5. Better fetal oxygenation

Cephalic presentation typically allows for optimal positioning of the baby’s head, which facilitates adequate blood flow and oxygenation, contributing to the baby’s well-being during labor and delivery.

Factors such as the cephalic posterior position of the baby and a narrow maternal pelvis can increase the likelihood of complications during childbirth. Occasionally, infants in the cephalic presentation may exhibit a backward tilt of their heads, potentially leading to preterm delivery in rare instances.

In addition to cephalic presentation, there are several other fetal positions that can occur during pregnancy and childbirth, each with its own associated risks. These positions can impact the delivery process and may require different management strategies. Here are two common fetal positions and their associated risks:

1. Breech Presentation

• Babies in breech presentation, where the buttocks or feet are positioned to enter the birth canal first, are at higher risk of birth injuries such as hip dysplasia or brachial plexus injuries.
• Breech presentation can lead to complications during labor and delivery, including umbilical cord prolapse, entrapment of the head, or difficulty delivering the shoulders, necessitating interventions such as cesarean section.

2. Transverse Lie Presentation

• Transverse lie , where the baby is positioned sideways across the uterus, often leads to prolonged labor and increases the likelihood of cesarean section due to difficulties in the baby’s descent through the birth canal.
• The transverse position of the baby may result in compression of the umbilical cord during labor, leading to decreased oxygen supply and potential fetal distress. This situation requires careful monitoring and intervention to ensure the baby’s well-being.

When a foetus is moving into the cephalic position, it is known as ‘head engagement’. The baby stars getting into this position in the third trimester, between the 32nd and the 36th weeks, to be precise. When the head engagement begins, the foetus starts moving down into the pelvic canal. At this stage, very little of the baby is felt in the abdomen, but more is felt moving downward into the pelvic canal in preparation for birth.

You may think that in order to find out if your baby has a cephalic presentation, an ultrasound is your only option. This is not always the case. You can actually find out the position of your baby just by touching and feeling their movements.

By rubbing your hand on your belly, you might be able to feel their position. If your baby is in the cephalic position, you might feel their kicks in the upper stomach. Whereas, if the baby is in the breech position, you might feel their kicks in the lower stomach.

Even in the cephalic position, it may be possible to tell if your baby is in the anterior position or in the posterior position. When your baby is in the anterior position, they may be facing your back. You may be able to feel your baby move underneath your ribs. It is likely that your belly button will also pop out.

When your baby is in the posterior position, you will usually feel your baby start to kick you in your stomach. When your baby has its back pressed up against your back, your stomach may not look rounded out, but flat instead.

Mothers whose placentas have attached in the front, something known as anterior placenta , you may not be able to feel the movements of your baby as well as you might like to.

Breech babies can make things complicated. Both the mother and the baby will face some problems. A breech baby is positioned head-up and bottom down. In order to deliver the baby, the birth canal needs to open a lot wider than it has to in the cephalic position. Besides this, your baby can get an arm or leg entangled while coming out.

If your baby is in the breech position, there are some things that you can do to encourage the baby to get into the cephalic position. There are a few exercises that could help such as pelvic tilts , swimming , spending a bit of time upside down, and belly dancing are a few ways you can try yourself to get your baby into the head-down position .

If this is not working either, your doctor will try an ECV (External Cephalic Version) . Here, your doctor will be hands-on, applying some gentle, but firm pressure to your tummy. In order to reach a cephalic position, the baby will need to be rolled into a bottom’s up position. This technique is successful around 50% of the time. When this happens, you will be able to have a normal vaginal delivery.

Though it sounds simple enough to get the fetal presentation into cephalic, there are some risks involved with ECV. If your doctor notices your baby’s heart rate starts to become problematic, the doctor will stop the procedure right away.

Encouraging a baby to move into the cephalic position, where the head is down towards the birth canal, is often desirable for smoother labor and delivery. While medical interventions may be necessary in some cases, there are natural methods that pregnant individuals can try to help facilitate this positioning. Here are several techniques that may help turn a baby into the cephalic position:

1. Optimal Maternal Positioning

Maintaining positions such as kneeling, hands and knees, or pelvic tilts may encourage the baby to move into the cephalic position by utilizing gravity and reducing pressure on the pelvis.

2. Spinning Babies Techniques

Specific exercises and positions recommended by the Spinning Babies organization, such as Forward-Leaning Inversion or the Sidelying Release, aim to promote optimal fetal positioning and may help encourage the baby to turn cephalic.

3. Chiropractic Care or Acupuncture

Some individuals find that chiropractic adjustments or acupuncture sessions with qualified practitioners can help address pelvic misalignment or relax tight muscles, potentially creating more space for the baby to maneuver into the cephalic position.

4. Prenatal Yoga and Swimming

Engaging in gentle exercises like prenatal yoga or swimming may help promote relaxation, reduce stress on the uterine ligaments, and encourage the baby to move into the cephalic position naturally. These activities also support overall physical and mental well-being during pregnancy.

1. What factors influence whether my baby will be in cephalic presentation?

Several factors can influence your baby’s position during pregnancy, including the shape and size of your uterus, the strength of your abdominal muscles, the amount of amniotic fluid, and the position of the placenta . Additionally, your baby’s own movements and preferences play a role.

2. Is it necessary for my baby to be in cephalic presentation for a vaginal delivery?

While cephalic presentation is considered the optimal position for vaginal delivery, some babies born in non-cephalic presentations can still be safely delivered vaginally with the guidance of a skilled healthcare provider. However, certain non-cephalic presentations may increase the likelihood of needing a cesarean section.

3. What can I do to encourage my baby to stay in the cephalic presentation?

Maintaining good posture, avoiding positions that encourage the baby to settle into a breech or transverse lie, staying active with gentle exercises, and avoiding excessive reclining can all help encourage your baby to remain in the cephalic presentation. Additionally, discussing any concerns with your healthcare provider and following their recommendations can be beneficial.

This was all about fetus with cephalic presentation. Most babies get into the cephalic position on their own. This is the most ideal situation as there will be little to no complications during normal vaginal labour. There are different cephalic positions, but these should not cause a lot of issues. If your baby is in any position other than cephalic in pregnancy, you may need C-Section . Keep yourself updated on the smallest of progress during your pregnancy so that you are aware of everything that is going on. Go for regular check-ups as your doctor will be able to help you if a complication arises during acephalic presentation at 20, 28 and 30 weeks.

References/Resources:

1. Glezerman. M; Planned vaginal breech delivery: current status and the need to reconsider (Expert Review of Obstetrics & Gynecology); Taylor & Francis Online; https://www.tandfonline.com/doi/full/10.1586/eog.12.2 ; January 2014

2. Feeling your baby move during pregnancy; UT Southwestern Medical Center; https://utswmed.org/medblog/fetal-movements/

3. Fetal presentation before birth; Mayo Clinic; https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/fetal-positions/art-20546850

4. Fetal Positions; Cleveland Clinic; https://my.clevelandclinic.org/health/articles/9677-fetal-positions-for-birth

5. FAQs: If Your Baby Is Breech; American College of Obstetricians and Gynecologists; https://www.acog.org/womens-health/faqs/if-your-baby-is-breech

6. Roecker. C; Breech repositioning unresponsive to Webster technique: coexistence of oligohydramnios (Journal of Chiropractic Medicine); Science Direct; https://www.sciencedirect.com/science/article/abs/pii/S1556370713000588 ; June 2013

7. Presentation and position of baby through pregnancy and at birth; Pregnancy, Birth & Baby; https://www.pregnancybirthbaby.org.au/presentation-and-position-of-baby-through-pregnancy-and-at-birth

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Why Is Cephalic Presentation Ideal For Childbirth?

5   Dec   2017 | 8 min Read

During labour, contractions stretch your birth canal so that your baby has adequate room to come through during birth. The cephalic presentation is the safest and easiest way for your baby to pass through the birth canal.

If your baby is in a non-cephalic position, delivery can become more challenging. Different fetal positions pose a range of difficulties and varying risks and may not be considered ideal birthing positions.

Two Kinds of Cephalic Positions

There are two kinds of cephalic positions:

• Cephalic occiput anterior , where your baby’s head is down and is facing toward your back.
• Cephalic occiput posterior , where your baby is positioned head down, but they are facing your abdomen instead of your back. This position is also nicknamed ‘sunny-side-up’ and can increase the chances of prolonged and painful delivery. 

How to Know if Your Baby is In a Cephalic Position?

You can feel your baby’s position by rubbing your hand on your belly. If you feel your little one’s stomach in the upper stomach, then your baby is in a cephalic position. But if you feel their kicks in the lower stomach, then it could mean that your baby is in a breech position.

You can also determine whether your baby is in the anterior or posterior cephalic position. If your baby is in the anterior position, you may feel their movement underneath your ribs and your belly button could also pop out. If your baby is in the posterior position, then you may feel their kicks in their abdomen, and your stomach may appear rounded up instead of flat. 

You can also determine your baby’s position through an ultrasound scan or a physical examination at your healthcare provider’s office. 

Benefits of Cephalic Presentation in Pregnancy

Cephalic presentation is one of the most ideal birth positions, and has the following benefits:

• It is the safest way to give birth as your baby’s position is head-down and prevents the risk of any injuries.
• It can help your baby move through the delivery canal as safely and easily as possible.
• It increases the chances of smooth labour and delivery.

Are There Any Risks Involved in Cephalic Position?

Conditions like a cephalic posterior position in addition to a narrow pelvis of the mother can increase the risk of pregnancy complications during delivery. Some babies in the head-first cephalic presentation might have their heads tilted backward. This may, in some rare cases, cause preterm delivery.

What are the Risks Associated with Other Birth Positions?

A small percentage of babies may settle into a non-cephalic position before their birth. This can pose risks to both your and your baby’s health, and also influence the way in which you deliver. 

In the next section, we have discussed a few positions that your baby can settle in throughout pregnancy, as they move around the uterus. But as they grow old, there will be less space for them to tumble around, and they will settle into their final position. This is when non-cephalic positions can pose a risk.  

Breech Position

There are three types of breech fetal positioning:

• Frank breech : Your baby’s legs stick straight up along with their feet near their head.
• Footling breech: One or both of your baby’s legs are lowered over your cervix.
• Complete breech: Your baby is positioned bottom-first with their knees bent.

If your baby is in a breech position , vaginal delivery is considered complicated. When a baby is born in breech position, the largest part of their body, that is, their head is delivered last. This can lead to injury or even fetal distress. Moreover, the umbilical cord may also get damaged or get wrapped around your baby’s neck, cutting off their oxygen supply.  

If your baby is in a breech position, your healthcare provider may recommend a c-section, or they may try ways to flip your baby’s position in a cephalic presentation.

Transverse Lie

In this position, your baby settles in sideways across the uterus rather than being in a vertical position. They may be:

• Head-down, with their back facing the birth canal
• One shoulder pointing toward the birth canal
• Up with their hands and feet facing the birth canal

If your baby settles in this position, then your healthcare provider may suggest a c-section to reduce the risk of distress in your baby and other pregnancy complications.

Turning Your Baby Into A Cephalic Position

External cephalic version (ECV) is a common, and non-invasive procedure that helps turn your baby into a cephalic position while they are in the womb. However, your healthcare provider may only consider this procedure if they consider you have a stable health condition in the last trimester, and if your baby hasn’t changed their position by the 36th week.

You can also try some natural remedies to change your baby’s position, such as:

• Lying in a bridge position: Movements like bridge position can sometimes help move your baby into a more suitable position. Lie on your back with your feet flat on the ground and your legs bent. Raise your pelvis and hips into a bridge position and hold for 5-10 minutes. Repeat several times daily.
• Chiropractic care: A chiropractor can help with the adjustment of your baby’s position and also reduce stress in them.
• Acupuncture: After your doctor’s go-ahead, you can also consider acupuncture to get your baby to settle into an ideal birthing position.

While most babies settle in a cephalic presentation by the 36th week of pregnancy, some may lie in a breech or transverse position before birth. Since the cephalic position is considered the safest, your doctor may recommend certain procedures to flip your baby’s position to make your labour and delivery smooth. You may also try the natural methods that we discussed above to get your baby into a safe birthing position and prevent risks or other pregnancy complications. 

When Should A Baby Be In A Cephalic Position?

Your baby would likely naturally drop into a cephalic position between weeks 37 to 40 of your pregnancy .

Is Cephalic Position Safe?

Research shows that 95% of babies take the cephalic position a few weeks or days before their due date. It is considered to be the safest position. It ensures a smooth birthing process.

While most of the babies are in cephalic position at delivery, this is not always the case. If you have a breech baby, you can discuss the available options for delivery with your doctor.

Does cephalic presentation mean labour is near?

Head-down is the ideal position for your baby within your uterus during birth. This is known as the cephalic position. This posture allows your baby to pass through the delivery canal more easily and safely.

Can babies change from cephalic to breech?

The external cephalic version (ECV) is the most frequent procedure used for turning a breech infant.

How can I keep my baby in a cephalic position?

While your baby naturally gets into this position, you can try some exercises to ensure that they settle in cephalic presentation. Exercises such as breech tilt, forward-leaning position (spinning babies program), cat and camel pose can help.

Stitches after a normal delivery : How many stitches do you need after a vaginal delivery? Tap this post to know.

Vaginal birth after caesarean delivery : Learn all about the precautions to consider before having a vaginal delivery after a c-section procedure. 

How many c-sections can you have : Tap this post to know the total number of c-sections that you can safely have.

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Cephalic Presentation Definition

Cephalic presentation is the most common type of fetal presentation, in which the baby is in a head-down position in the uterus. In this position, the baby’s head is the first part of the body to come out of the mother’s vagina. Cephalic presentation is also sometimes called vertex presentation, although the latter is only one of the different categories of the former. This fetus turning to this position happens during the last three months of pregnancy.

The process by which the fetus moves from a breech to a cephalic position is known as head engagement. This occurs when the baby’s head is able to move down into the pelvis. The chin and forehead will press against the sacrum, and the occiput will press against the back of the mother’s pubic bone.

Other Types of Cephalic Presentations

The cephalic presentation can be further classified, according to the degree of flexion of the fetal head. A presentation is considered vertex if the fetal head is well-flexed. An incomplete flexion is called a sinciput presentation, a partially deflexed head is called a brow presentation, and a completely extended head is called a face presentation.

This image shows how often the term ‘Cephalic presentation” is used in relation to other, similar birth terms:

Other Types of Fetal Presentations

There are other types of presentations , including breech presentation, shoulder presentation, and transverse presentation . Breech presentation occurs when the baby’s buttocks or feet are the first to come out of the vagina. Shoulder presentation occurs when the baby’s arm or shoulder is the first to come out of the vagina. Transverse presentation occurs when the baby is lying across the uterus, instead of head-down.

These presentations other types of presentations, but they are much less common than cephalic presentation. In fact, breech presentation occurs in only about 3 percent of births, and shoulder presentation occurs in only 1 percent of births. transverse presentation occurs in even fewer pregnancies, about 0.5 percent. Giving birth with these presentations come along with certain risks.

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If Your Baby Is Breech

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Frequently Asked Questions Expand All

In the last weeks of pregnancy, a fetus usually moves so his or her head is positioned to come out of the vagina first during birth. This is called a vertex presentation . A breech presentation occurs when the fetus’s buttocks, feet, or both are in place to come out first during birth. This happens in 3–4% of full-term births.

It is not always known why a fetus is breech. Some factors that may contribute to a fetus being in a breech presentation include the following:

You have been pregnant before.

There is more than one fetus in the uterus (twins or more).

There is too much or too little amniotic fluid .

The uterus is not normal in shape or has abnormal growths such as fibroids .

The placenta covers all or part of the opening of the uterus ( placenta previa )

The fetus is preterm .

Occasionally fetuses with certain birth defects will not turn into the head-down position before birth. However, most fetuses in a breech presentation are otherwise normal.

Your health care professional may be able to tell which way your fetus is facing by placing his or her hands at certain points on your abdomen. By feeling where the fetus's head, back, and buttocks are, it may be possible to find out what part of the fetus is presenting first. An ultrasound exam or pelvic exam may be used to confirm it.

External cephalic version (ECV) is an attempt to turn the fetus so that he or she is head down. ECV can improve your chance of having a vaginal birth. If the fetus is breech and your pregnancy is greater than 36 weeks your health care professional may suggest ECV.

ECV will not be tried if:

You are carrying more than one fetus

There are concerns about the health of the fetus

You have certain abnormalities of the reproductive system

The placenta is in the wrong place

The placenta has come away from the wall of the uterus ( placental abruption )

ECV can be considered if you have had a previous cesarean delivery .

The health care professional performs ECV by placing his or her hands on your abdomen. Firm pressure is applied to the abdomen so that the fetus rolls into a head-down position. Two people may be needed to perform ECV. Ultrasound also may be used to help guide the turning.

The fetus's heart rate is checked with fetal monitoring before and after ECV. If any problems arise with you or the fetus, ECV will be stopped right away. ECV usually is done near a delivery room. If a problem occurs, a cesarean delivery can be performed quickly, if necessary.

Complications may include the following:

Prelabor rupture of membranes

Changes in the fetus's heart rate

Placental abruption

Preterm labor

More than one half of attempts at ECV succeed. However, some fetuses who are successfully turned with ECV move back into a breech presentation. If this happens, ECV may be tried again. ECV tends to be harder to do as the time for birth gets closer. As the fetus grows bigger, there is less room for him or her to move.

Most fetuses that are breech are born by planned cesarean delivery. A planned vaginal birth of a single breech fetus may be considered in some situations. Both vaginal birth and cesarean birth carry certain risks when a fetus is breech. However, the risk of complications is higher with a planned vaginal delivery than with a planned cesarean delivery.

In a breech presentation, the body comes out first, leaving the baby’s head to be delivered last. The baby’s body may not stretch the cervix enough to allow room for the baby’s head to come out easily. There is a risk that the baby’s head or shoulders may become wedged against the bones of the mother’s pelvis. Another problem that can happen during a vaginal breech birth is a prolapsed umbilical cord . It can slip into the vagina before the baby is delivered. If there is pressure put on the cord or it becomes pinched, it can decrease the flow of blood and oxygen through the cord to the baby.

Although a planned cesarean birth is the most common way that breech fetuses are born, there may be reasons to try to avoid a cesarean birth.

A cesarean delivery is major surgery. Complications may include infection, bleeding, or injury to internal organs.

The type of anesthesia used sometimes causes problems.

Having a cesarean delivery also can lead to serious problems in future pregnancies, such as rupture of the uterus and complications with the placenta.

With each cesarean delivery, these risks increase.

If you are thinking about having a vaginal birth and your fetus is breech, your health care professional will review the risks and benefits of vaginal birth and cesarean birth in detail. You usually need to meet certain guidelines specific to your hospital. The experience of your health care professional in delivering breech babies vaginally also is an important factor.

Amniotic Fluid : Fluid in the sac that holds the fetus.

Anesthesia : Relief of pain by loss of sensation.

Breech Presentation : A position in which the feet or buttocks of the fetus would appear first during birth.

Cervix : The lower, narrow end of the uterus at the top of the vagina.

Cesarean Delivery : Delivery of a fetus from the uterus through an incision made in the woman’s abdomen.

External Cephalic Version (ECV) : A technique, performed late in pregnancy, in which the doctor attempts to manually move a breech baby into the head-down position.

Fetus : The stage of human development beyond 8 completed weeks after fertilization.

Fibroids : Growths that form in the muscle of the uterus. Fibroids usually are noncancerous.

Oxygen : An element that we breathe in to sustain life.

Pelvic Exam : A physical examination of a woman’s pelvic organs.

Placenta : Tissue that provides nourishment to and takes waste away from the fetus.

Placenta Previa : A condition in which the placenta covers the opening of the uterus.

Placental Abruption : A condition in which the placenta has begun to separate from the uterus before the fetus is born.

Prelabor Rupture of Membranes : Rupture of the amniotic membranes that happens before labor begins. Also called premature rupture of membranes (PROM).

Preterm : Less than 37 weeks of pregnancy.

Ultrasound Exam : A test in which sound waves are used to examine inner parts of the body. During pregnancy, ultrasound can be used to check the fetus.

Umbilical Cord : A cord-like structure containing blood vessels. It connects the fetus to the placenta.

Uterus : A muscular organ in the female pelvis. During pregnancy, this organ holds and nourishes the fetus.

Vagina : A tube-like structure surrounded by muscles. The vagina leads from the uterus to the outside of the body.

Vertex Presentation : A presentation of the fetus where the head is positioned down.

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Published: January 2019

Last reviewed: August 2022

Copyright 2024 by the American College of Obstetricians and Gynecologists. All rights reserved. Read copyright and permissions information . This information is designed as an educational aid for the public. It offers current information and opinions related to women's health. It is not intended as a statement of the standard of care. It does not explain all of the proper treatments or methods of care. It is not a substitute for the advice of a physician. Read ACOG’s complete disclaimer .

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What to Read Next

Cesarean Birth

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Breech presentation

• Overview  
• Theory  
• Diagnosis  
• Management  
• Follow up  
• Resources  

Breech presentation refers to the baby presenting for delivery with the buttocks or feet first rather than head.

Associated with increased morbidity and mortality for the mother in terms of emergency cesarean section and placenta previa; and for the baby in terms of preterm birth, small fetal size, congenital anomalies, and perinatal mortality.

Incidence decreases as pregnancy progresses and by term occurs in 3% to 4% of singleton term pregnancies.

Treatment options include external cephalic version to increase the likelihood of vaginal birth or a planned cesarean section, the optimal gestation being 37 and 39 weeks, respectively.

Planned cesarean section is considered the safest form of delivery for infants with a persisting breech presentation at term.

Breech presentation in pregnancy occurs when a baby presents with the buttocks or feet rather than the head first (cephalic presentation) and is associated with increased morbidity and mortality for both the mother and the baby. [1] Cunningham F, Gant N, Leveno K, et al. Williams obstetrics. 21st ed. New York: McGraw-Hill; 1997. [2] Kish K, Collea JV. Malpresentation and cord prolapse. In: DeCherney AH, Nathan L, eds. Current obstetric and gynecologic diagnosis and treatment. New York: McGraw-Hill Professional; 2002. There is good current evidence regarding effective management of breech presentation in late pregnancy using external cephalic version and/or planned cesarean section.

History and exam

Key diagnostic factors.

• buttocks or feet as the presenting part
• fetal head under costal margin
• fetal heartbeat above the maternal umbilicus

Other diagnostic factors

• subcostal tenderness
• pelvic or bladder pain

Risk factors

• premature fetus
• small for gestational age fetus
• nulliparity
• fetal congenital anomalies
• previous breech delivery
• uterine abnormalities
• abnormal amniotic fluid volume
• placental abnormalities
• female fetus

Diagnostic tests

1st tests to order.

• transabdominal/transvaginal ultrasound

Treatment algorithm

<37 weeks' gestation and in labor, ≥37 weeks' gestation not in labor, ≥37 weeks' gestation in labor: no imminent delivery, ≥37 weeks' gestation in labor: imminent delivery, contributors, natasha nassar, phd.

Associate Professor

Menzies Centre for Health Policy

Sydney School of Public Health

University of Sydney

Disclosures

NN has received salary support from Australian National Health and a Medical Research Council Career Development Fellowship; she is an author of a number of references cited in this topic.

Christine L. Roberts, MBBS, FAFPHM, DrPH

Research Director

Clinical and Population Health Division

Perinatal Medicine Group

Kolling Institute of Medical Research

CLR declares that she has no competing interests.

Jonathan Morris, MBChB, FRANZCOG, PhD

Professor of Obstetrics and Gynaecology and Head of Department

JM declares that he has no competing interests.

Peer reviewers

John w. bachman, md.

Consultant in Family Medicine

Department of Family Medicine

Mayo Clinic

JWB declares that he has no competing interests.

Rhona Hughes, MBChB

Lead Obstetrician

Lothian Simpson Centre for Reproductive Health

The Royal Infirmary

RH declares that she has no competing interests.

Brian Peat, MD

Director of Obstetrics

Women's and Children's Hospital

North Adelaide

South Australia

BP declares that he has no competing interests.

Lelia Duley, MBChB

Professor of Obstetric Epidemiology

University of Leeds

Bradford Institute of Health Research

Temple Bank House

Bradford Royal Infirmary

LD declares that she has no competing interests.

Justus Hofmeyr, MD

Head of the Department of Obstetrics and Gynaecology

East London Private Hospital

East London

South Africa

JH is an author of a number of references cited in this topic.

Differentials

• Transverse lie
• Caesarean birth
• Mode of term singleton breech delivery

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You and your baby at 32 weeks pregnant

Your baby at 32 weeks.

By about 32 weeks, the baby is usually lying with their head pointing downwards, ready for birth. This is known as cephalic presentation.

If your baby is not lying head down at this stage, it's not a cause for concern – there's still time for them to turn.

The amount of amniotic fluid in your uterus is increasing, and your baby is still swallowing fluid and passing it out as urine.

You at 32 weeks

Being active and fit during pregnancy will help you adapt to your changing shape and weight gain. It can also help you cope with labour and get back into shape after the birth.

Find out about exercise in pregnancy .

You may develop pelvic pain in pregnancy. This is not harmful to your baby, but it can cause severe pain and make it difficult for you to get around.

Find out about ways to tackle pelvic pain in pregnancy .

Read about the benefits of breastfeeding for you and your baby. It's never too early to start thinking about how you're going to feed your baby, and you do not have to make up your mind until your baby is born.

Things to think about

• how you might feel after the birth

Start4Life has more about you and your baby at 32 weeks pregnant .

You can sign up for Start4Life's weekly emails for expert advice, videos and tips on pregnancy, birth and beyond.

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Pregnancy and Fetal Development: Cephalic Presentation and Other Descriptive Ultrasonographic Findings from Clinically Healthy Bottlenose Dolphins ( Tursiops truncatus ) under Human Care

Pietro saviano.

1 Ambulatorio Veterinario Saviano-Larocca, 41042 Spezzano, Italy; ti.liamtoh@orteiprd (P.S.); ti.ecila@ednargarf (F.G.)

Letizia Fiorucci

2 Facultad de Veterinaria, Universidad de Las Palmas de Gran Canaria, Arucas, 35416 Las Palmas de Gran Canaria, Spain

Francesco Grande

Roberto macrelli.

3 Dipartimento di Scienze Pure e Applicate, Università di Urbino, 61029 Urbino, Italy; ti.orebil@otreborcam

Alessandro Troisi

4 Scuola di Bioscienze e Medicina Veterinaria, Università di Camerino, 62024 Matelica, Italy; [email protected]

Angela Polisca

5 Dipartimento di Medicina Veterinaria, Università di Perugia, 06124 Perugia, Italy; [email protected]

Riccardo Orlandi

6 Tyrus Veterinary Clinic, 05100 Terni, Italy; [email protected]

Simple Summary

Ultrasound data are vital for monitoring and detecting problems in pregnancies, and although there is a significant amount of data for domestic species, data for marine mammals are scarce. In domestic species, the use of ultrasonography to monitor a pregnancy usually has the following aims: fetal movements, fetal heart rates, measurements of the skull and the thorax for the prediction of the birth date interval, the morphological aspects of the fetal organs, the appearance of the umbilical cord, and the placentation. The purpose of this study is to provide to the clinician additional relevant data on fetal development and well-being during a dolphin pregnancy that may also be useful for wild population monitoring. This study is the result of a retrospective analysis of 192 ultrasound scans over 10 years that, for the first time, describes the sonographic findings of the bottlenose dolphin organogenesis and their correlation with the stage of pregnancy, as well as the calf presentation at birth, according to its position within the uterus, and moreover a complete literature review.

Ultrasonography is widely used in veterinary medicine for the diagnosis of pregnancy, and can also be used to monitor abnormal pregnancies, embryonic resorption, or fetal abortion. Ultrasonography plays an important role in modern-day cetacean preventative medicine because it is a non-invasive technique, it is safe for both patient and operator, and it can be performed routinely using trained responses that enable medical procedures. Reproductive success is an important aspect of dolphin population health, as it is an indicator of the future trajectory of the population. The aim of this study is to provide additional relevant data on feto-maternal ultrasonographic monitoring in bottlenose dolphin ( Tursiops truncatus ) species, for both the clinicians and for in situ population studies. From 2009 to 2019, serial ultrasonographic exams of 11 healthy bottlenose dolphin females kept under human care were evaluated over the course of 16 pregnancies. A total of 192 ultrasound exams were included in the study. For the first time, the sonographic findings of the bottlenose dolphin organogenesis and their correlation with the stage of pregnancy are described. Furthermore, this is the first report that forecasts the cephalic presentation of the calf at birth, according to its position within the uterus.

1. Introduction

A preventative medicine program is one of the key factors in health evaluation for ensuring the welfare of dolphins under human care. Ultrasonography (US) plays an important role in modern-day cetacean preventative medicine because it is a non-invasive technique, it is safe for both patient and operator, and it can be performed routinely using trained responses that enable medical procedures [ 1 , 2 ]. Ultrasound data are vital for monitoring and detecting problems in pregnancies, and while there is a significant amount of data for domestic species [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ], data for marine mammals are scarce [ 12 , 13 , 14 ]. In domestic species, US is often used for the early identification of fetal pathologies and reabsorption, for example, altered/slowed down growth, loss of fetal fluids with decrease in the size of the vesicle and alteration of its shape, absence of heartbeat, blurring of margins and alteration of normal fetal anatomy, and detachment of the placenta from the uterine wall [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ]. In marine mammal medicine, in the past, US was used only to confirm a pregnancy; however, an increasing number of facilities are now monitoring gestation by US, and further studies are now emerging with additional reference ranges.

Reproductive success is an important aspect of dolphin population health, as it is an indicator of the future trajectory of the population [ 15 , 16 ]. Pregnancy determination for wild dolphins, including differentiation of pregnancy stage, is possible during capture–release health assessments through application of diagnostic ultrasound to evaluate fetal development and viability, estimate gestational age, and measure anatomical structures [ 15 , 16 ]. The use of ultrasound for systematic pregnancy determination provides a useful tool for measuring an important component of reproductive success. Application of this approach for conservation of wild populations benefits from the establishment of baseline values, such as the estimates provided herein for the reference population of bottlenose dolphins [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ].

The brightness (B)-mode technique is based on a process in which focused beams are iteratively sent into the body and the received waves are used to form an image scan-line, covering line-by-line the region of interest. The use of it to monitor bottlenose dolphin pregnancy dates back to the early 1990s, when Williamson et al. (1990) diagnosed pregnancy in a limited number of subjects ( n = 4), at approximately the fourth month of gestation, being able to visualize fetal movements and fluids. Periodic monitoring allowed the authors to observe fetal vitality through the observation of cardiac mechanics and to carry out measurements both of the cranial diameter (on the front–occipital axis) and of the thoracic diameter, obtaining linear growth diagrams [ 23 ]. The authors showed difficulties in obtaining clear ultrasonographic images, both because the dolphins were uncooperative during the exam due to scarce training, and due to the features of the transducers used at the time. As regards the positioning of the transducer in the first months of gestation, the midline between the genital opening and the navel was used as a landmark, obtaining images in cross section, whereas in late pregnancy the probe was placed longitudinally, at 10–20 cm from the ventral midline [ 23 ]. Stone et al. (1999) observed a similar pattern of linear growth in bottlenose dolphins by measuring bi-parietal and thoracic fetal diameters from week 46 up to 1 week after delivery [ 24 ].

Lacave in her work developed an easy-to-use computer program to provide better birth prediction for regularly scanned dolphins during their gestation and to predict dolphin delivery dates, even with only one or two ultrasound scans of their animals [ 25 ]. Measurement of bi-parietal diameters is only possible when the head is distinguishable from the rest of the body; the head is presented ultrasonographically as a symmetrical ovoid structure and the bi-parietal diameters are measured where they reach their maximum amplitude [ 25 ]. For thoracic diameters, Lacave et al. (2004) used, as a reference point, the section where all cardiac chambers, symmetrically surrounded by the lungs, appear in the ultrasound image in the same section and where pectoral fins are also frequently visible. Lacave showed how the diameters of the skull increase more slowly than the thoracic diameters, and that the thoracic diameters represent the limit of accuracy in late pregnancy [ 25 ].

Sklansky et al. (2010) recognize the utility of fetal echocardiography as a safe technique able to evaluate the cardiovascular system in the bottlenose dolphin, especially in the period between the eighth and the ninth month of gestation. As in humans, this technique allows us to identify congenital cardiac anomalies [ 26 , 27 , 28 ] and to identify the possible causes of perinatal mortality risk associated with physiological abnormalities and cardiac hemodynamics [ 29 , 30 ]. In most cases, the optimal visualization of the fetal heart is obtained by positioning the pregnant female in lateral decubitus, homolaterally to the uterine horn in which the fetus is housed [ 26 , 27 ]. The optimal window is located near the maternal navel, proximal to the dorsal and caudal–ventral fin compared to the caudal fin. As expected, the cardiac dimensions increased with the approaching birth; passing from 3 to 6 cm of the 9th month up to 8–9 cm of the 10th month [ 26 , 27 ].

Recently, Ivancic et al. (2020) developed a protocol for feto-maternal ultrasonographic monitoring in bottlenose dolphins. In their work, a total of 203 US exams were performed during a 7-year period to monitor 16 pregnancies. The authors reported normal measurements and descriptive findings correlated with a positive outcome—fetal bi-parietal diameter, thoracic width in dorsal and transverse planes, thoracic height in a sagittal plane, aortic diameter, and blubber thickness all demonstrated a high correlation with date of gestation [ 21 ].

Umbilical cord accidents were diagnosed in the same dolphin in three consecutive pregnancies in a study by García-Párraga et al. (2014). The trans-abdominal ultrasound evaluation revealed the presence of a wrap of the umbilical cord around the fetal peduncle. All pregnancies ended in in utero death of fetuses and their expulsion [ 31 ]. In addition, an omphalocele (an abdominal wall defect at the base of the umbilical cord) in an approximately 16-week-old fetus was detected in the clinical case reported by Smith et al. (2013), thanks to the US prenatal examination. Color Doppler was utilized to study the blood flow within the omphalocele, as well as diagnose an associated anomaly of the umbilical cord, which contained three vessels instead of four [ 32 ]. Finally, the case of meconium aspiration syndrome (MAS) in a male neonate of bottlenose dolphin who died immediately after birth was reported by Tanaka et al. in 2014. At necropsy, a knot was found in the umbilical cord [ 33 ]. The lungs showed diffuse intra-alveolar edema, hyperemic congestion, and atelectasis due to meconium aspiration with mild inflammatory cell infiltration. Although the exact cause of MAS in this case was unknown, fetal hypoxia due possibly to the umbilical knot might have been associated with MAS, which is the first report in dolphins. MAS due to perinatal asphyxia should be taken into account as a possible cause of neonatal mortality and stillbirth of dolphin calves [ 33 ].

Valuable information about the ontogeny of the body systems and their development in cetacean species, the precise time intervals of such developments, and any distinctive growth trajectories are basically unknown, because descriptions are based on occasional recoveries of embryos and fetuses and it very difficult to acquire complete ontogenic series [ 34 , 35 , 36 , 37 , 38 , 39 ]. Fetal abnormalities have been observed in cetaceans, as in other species. Brook, in 1994, for the first time, described the ultrasound diagnosis of an anencephaly, a lethal form of cephalic axial skeletal-neuronal disraphism, in a Tursiops aduncus fetus [ 34 ]. The fetal skull base appeared disproportionately small, and the cranium could not be identified. Fetal heart motion could be detected throughout the gestation. After a period of 357 days after conception, an uncomplicated, spontaneous delivery produced a stillborn male anencephalic calf. The abnormality was associated with various factors including respiratory tract infection in early gestation and folic acid deficiency. This case illustrates the ability of US to provide assessment of fetal morphology and growth, information not available by other means [ 34 ]. Ultrasonography proved to be appropriate to monitor fetal development, placenta and fetal membranes, and also to identify umbilical cord defects, thanks to the monitoring of its position and perfusion. This method has the advantage that it can identify abnormalities at early gestational stages [ 21 , 34 ], and that regular measurements allow monitoring of fetal growth and provide a more accurate prediction of expected delivery [ 25 ], so that adequate arrangements can be made in good time. The aim of this retrospective study was to provide additional relevant descriptive findings on feto-maternal ultrasonographic monitoring protocols in bottlenose dolphin species, thanks to the analysis of 192 ultrasound exams during a 10-year period. The data obtained may be very useful for the future clinical practice for managed population and in situ population studies, as it can be used to improve the understanding of the pathophysiology of reproductive failure.

2. Materials and Methods

2.1. study animals.

This study is the result of a retrospective analysis of 192 ultrasound scans obtained during the routine pregnancy check of bottlenose dolphins and from the marine mammal ultrasound consulting work in 11 different facilities over 10 years. All the examinations were included in the preventative medicine protocol of each facility, and no additional examinations were performed. From 2009 to 2019, serial ultrasonographic exams of 11 healthy bottlenose dolphin females (average age: 18 ± 7 years; min–max: 9 to 36 years) kept under human care were evaluated over the course of 16 pregnancies. Three dams were pluriparous. The calves born were 10 males and 6 females; of these, 2 females died 9 days after birth due to a respiratory disease. Neither case was that of cephalic birth. Inclusion criteria involved all pregnancies ended with the birth of alive calves that survived at least 48 h after the delivery. Exclusion criteria included any pre-existing health conditions that could have affected pregnancy, abortion, or any significant health conditions that occurred during pregnancy and required initiation of treatment by the attending clinician. A total of 192 ultrasound exams were included in the study. All examined animals were trained routinely for medical behaviors, including US. Lateral and ventral abdominal scanning was performed using seawater for acoustic coupling. For the study, the urogenital area was explored and the reproductive organs, ovaries, and uterus were evaluated. Uterine fluid echogenicity was assessed as anechoic, hypo-echoic, or hyper-echoic, as well as for the presence of echoic free-floating particles. Umbilical cord vasculature was assessed in cross section. Color Doppler confirmed vascular flow.

2.2. Ultrasonography: Instrumentation and Methodology

A portable SonoSite 180 Plus with a 2–5 MHz convex probe, an Esaote Mylab 25 gold with convex probe 2–5 MHz, an Aloka 900 with convex probe 2–5 MHz, and a General Electrics Logiq V2 with a 2–5 MHz curvilinear transducer were used to evaluate the dolphins during pregnancy. During the exam, the machine was covered with a transparent plastic bag to avoid accidental contact of the device with salt water. To avoid direct sunlight, a dark-colored bag was used to cover the instrument. The probe was waterproof. Acoustic gel was unnecessary because water provides an excellent medium through which to conduct ultrasound waves. Still images obtained were stored in DICOM (Digital Imaging and Communications in Medicine) format, whereas videos were also recorded using an external hard-disk.

2.3. Statistical Analyses

For each fetus, the time required for the appearance of each organ studied was analyzed. The quantitative variable “organ onset time” was introduced and a descriptive statistic expressed—average organ onset time with relative standard deviation. In addition, left or right ovulation rates and podalic or cephalic birth rates were analyzed. Medcalc, version 11.6.0.0, was used to analyze the data.

Considering the 16 pregnancies, the percentage of ovulation in the left ovary was 68.75%, whereas the ovulation in the right ovary was 31.25%, and it was of interest that two dams always ovulated in the right ovary. Maximum corpus luteum (CL) longitudinal diameter was 3.63 cm and transversal diameter was 3.02 cm ( Figure 1 ), even though the diameter may vary according to laterality. The results concerning the gonadal activity correspond to previous studies [ 18 , 19 , 20 ].

Corpus luteum (CL) with measurements.

The embryonic vesicle was recognizable at 29 ± 3 days post-ovulation on the apex of the uterine horn as a roundish structure with an average diameter of 1.21 cm with an anechoic content. In the following week, it was possible to recognize the embryo inside it as an elongated hyperechoic structure ( Figure 2 ).

( a ) The embryonic vesicle at 38 ± 2 days post-ovulation appeared as a roundish structure with an anechoic content and a hyper-echoic structure inside (V), under the CL. ( b ) At 52 ± 3 days, the embryo was perfectly recognizable (E).

The distinction between head and trunk was visible starting from 68 ± 5 days after ovulation. From the 216 ± 5 days of gestation, measurements started to be hard to realize with accuracy. In fact, in the evaluations after this last period, the position/orientation of the fetus and its size meant that it was not possible to take reliable measurements thereafter. Starting from 68 ± 5 days after ovulation, the embryonic cardiac mechanisms were displayed as a point of maximum fluctuation of the echoes. The heart rate was measured because the cardiac mechanics became visible and remained constant between 155 and 198 bpm until the ninth month of pregnancy ( Figure 3 ). During the last 3 months, it stabilized at 140 bpm, to reach 85 ± 5 bpm in the last 2 weeks of gestation. The first abdominal organs to be visualized were the stomach and the urinary bladder (98 ± 3 and 110 ± 2 days of gestation, respectively), which appeared as distinct and anechoic cavities. It was also possible to recognize the eye as an anechoic cavitary structure ( Figure 4 ).

( a ) The distinction between head and trunk was clear between 68 ± 5, up to the 216 ± 5 day of gestation. It allowed measurement of bi-parietal diameters. The umbilical cord was already easy guessed (as indicated by yellow arrow). ( b ) The fetal heart rate (HR) was measured once the cardiac mechanics became visible.

Fetal stomach (S) and fetal urinary bladder (B) were the first abdominal organs to be visualized, and appeared as distinct and anechoic cavities. The heart was recognizable as an anechoic cavity (H) and the embryonic cardiac mechanics were displayed as a point of maximum fluctuation of the echoes. The eye appeared as an anechoic cavitary structure (E).

The distinction between thorax and abdomen and, thus, the presence of the diaphragm, was seen at 92 ± 5 days of gestation. A clear distinction between lungs and liver was identified at 112 ± 5 days, whereas the ribs were visible at 153 ± 5 days. At 167 ± 3 days of gestation, the dorsal fin was visible as a hyper-echoic triangular structure in the dorsal portion of the trunk. During the same period, it was possible to identify the teeth. Even if the umbilical cord was easily guessed previously (as shown in Figure 3 ) from the 119 ± 6 day of gestation, it was clear as a hyper-echoic cordoniform structure, and it was important to evaluate the internal vascular components and the absence of knots or torsions until the birth ( Figure 5 ). Furthermore, it was possible to notice, between the 149th day and the 230th day of gestation, that the eye was open, the lens was visible, and eyelid movements were also detectable ( Figure 6 ).

( a ) From day 119 ± 6 of gestation, the umbilical cord was clear as a hyper-echoic cordoniform structure. ( b ) The small hypo-echoic central cavity is the urachus, shown by the yellow circle. ( c ) Color Doppler demonstrating flow within the umbilical vasculature: ( d ) the umbilical veins (in blue), and the umbilical arteries (in red).

From day 110 ± 2 of gestation, the eye appeared as anechoic cavitary structures, whereas starting from the 149th day, the lens was also visible. At 167 ± 3 days of gestation, it was possible to identify the teeth.

The intestine was visualized at 189 ± 5 days of gestation. The cardiac chambers were visualized 194 ± 5 days after ovulation, and after about 3 weeks, the vascular structures (aorta and caudal vena cava) departing from them were visualized ( Figure 7 ).

Fetal spinal cord (Sp), stomach (S), liver (Li), intestine (I), lungs (Lu), and heart (H) were visualized at 194 ± 5 days of gestation.

From the 230th day of gestation, it was possible to observe a ventral flexion of the caudal fin, a hyper-echoic structure, in contact with the abdomen. From the 245th to the 288th day of gestation, it was possible to recognize the thyroid and thymus ( Figure 8 ). During the last 3 months of gestation, it was possible to identify the kidneys.

( a ) At 245 ± 2 to 288 ± 2 days of gestation, it was possible to recognize the thyroid (T) and ( b ) the thymus, respectively.

In addition, it was possible to identify the genitalia and sex the fetus (males have a tri-lobed structure, whereas females have an apricot-shaped structure, as shown in Figure 9 ).

( a ) An ultrasound image of female genitals (apricot-shaped) by SonoSite 180 Plus with a 2–5 MHz convex probe; ( b ) the same area caught with General Electrics Logiq V2, with a 2–5 MHz convex probe.

Starting from the 301th post-ovulation day until the end of pregnancy, it is very difficult to obtain images of the caudal portions of the fetus, due to the folded position it assumes within the maternal uterus. To the authors’ knowledge, this is the first study that reports the sonographic descriptive findings of the bottlenose dolphin organogenesis and their correlation with the stage of pregnancy as shown in Figure 10 ).

Bottlenose dolphin ( Tursiops truncatus ) organogenesis timeline table.

Allantoic and amniotic fluid are distinguishable in all examinations starting from the last trimester of pregnancy. Allantoic fluid appears as an anechoic fluid and the amniotic fluid appears as a hyper-echoic fluid, with an increasing number of echoic particles during the last period of pregnancy ( Figure 11 ).

( a ) Allantoic (A) and amniotic fluid (B) in early stage of pregnancy. ( b ) Allantoic fluid appears as an anechoic fluid (A), and the amniotic fluid appears as a hyper-echoic fluid, with an increasing amount of echoic particles during the last period of pregnancy (B).

Finally, fetal position was evaluated throughout the gestational period. Considering the 16 pregnancies, the percentage of fluke presentation was 93.75%, whereas the head presentation was 6.25%. It is interesting to note that they were all successful cephalic deliveries. According to the results of the present study, it is possible to predict the calf presentation at birth, considering its position in the uterus during the last trimester. Using the CL as a reference, if the fetus skull is located close to the CL, it will have a podalic position at birth ( Figure 12 ).

( a ) Using the CL as a reference, if the fetus skull is located close to the CL, it will have a podalic position at birth, ( b ) as shown in the image.

However, if the tail fluke is located close to the CL, it will have a cephalic position at birth ( Figure 13 ).

( a ) Using the CL as a reference, if the tail fluke (TF) is located close to the CL, it will have a cephalic position at birth, ( b ) as shown in the image.

To the authors’ knowledge, the present study reports the first bottlenose dolphin cephalic presentation documented by US.

4. Discussion

In the present retrospective study, we describe, by US, the genesis of the fetal organs (stomach, bladder, lungs, eye, intestine) and structures (column, appendices), and note that their appearance can be used to estimate the gestational period in the dolphin, in the absence of further information, as described in other species [ 40 ]. To the authors’ knowledge, this is the first study that reports the sonographic descriptive findings of bottlenose dolphin organogenesis and their correlation with the stage of pregnancy. The heart, while appearing visible already in the early stages of gestation, was displayed optimally between the eighth and the ninth month, allowing exclusion of the presence of detectable pathologies. As reported by Sedmera et al. (2003), there is a scant amount of data regarding heart development in cetaceans [ 41 ]. In their study, the authors examined samples from a unique collection of embryonic dolphin specimens macroscopically and histologically to learn more about normal cardiac development in the spotted dolphin. It was found that during the spotted dolphin’s 280 days of gestation, the heart completes septation at about 35 days. However, substantial trabecular compaction, which normally occurs in terrestrial mammals, as well as in humans at around the same time period, was delayed until day 60, when coronary circulation became established. By day 80, however, the heart gained a compacted, characteristic shape, with a single apex [ 41 ]. Considering the bottlenose dolphin’s 385 days of gestation, around 68 ± 5 days after ovulation, the results of the present study show how the heart was recognizable by US, and the embryonic cardiac mechanics were displayed as a point of maximum fluctuation of the echoes. An accurate index of fetus welfare is the fetal heart rate [ 26 , 27 , 28 , 29 , 30 ]. The heart rate was measured once the cardiac mechanics became visible, and remained constant between 155 and 198 bpm until the ninth month of pregnancy. During the last 3 months, it stabilized at 140 bpm, to reach 85 ± 5 bpm in the last 2 weeks of gestation.

The distinction between thorax and abdomen and, thus, the presence of the diaphragm, was seen between 92 ± 5 days of gestation, whereas the clear distinction between lungs and liver was identified at 112 ± 5 days of gestation. The correlation between the dolphin fetus organogenesis and the gestational period may help the clinician to identify the proximity of the delivery and any suspected anomaly in fetal development. In human literature, normal fetal lung and lung/liver echogenicity relationships facilitate early diagnosis of congenital bronchopulmonary abnormalities, and a decrease in the fetal lung/liver echogenicity has been shown to predict respiratory distress in newborns [ 21 ]. Regarding the two calves who died 9 days after birth due to a respiratory disease, there are no data that suggested lung alteration identified by ultrasound throughout the pregnancy. The two clinical cases had fetal development comparable with the other fetuses examined. The necropsy of both calves revealed postpartum pathological process as cause of death.

The umbilical cord has also been documented in ultrasound images, thus being able to exclude the presence of twisting nodes or echographically detectable defects of the same conditions that proved fatal in the bottlenose dolphins [ 31 , 32 , 33 ]. Color Doppler may be utilized to study the blood flow, as well as diagnose an associated anomaly of the umbilical cord, such as in the case of an onphalocele that contained three vessels instead of four [ 32 ]. It is worth mentioning that four vessels are needed as normal presentation, as shown in Figure 4 .

As described in other animals such as horses [ 42 ], during the last 20 days of pregnancy, amniotic fluid shows an increase of the echogenicity compared with allantoic fluid. Allantoic fluid has to remain completely anechoic during all the stages of pregnancy. Amniotic and allantoic fluids increase their volume during pregnancy, giving protection to the fetus. At the time of birth, allantoic fluid dilates the pathways of birth, whereas amniotic fluid has the function of lubricating the fetus [ 43 ]. The allantoic liquid is composed mainly of the urine of the fetus and has an anechoic aspect throughout the pregnancy [ 43 ]. The amniotic fluid envelops the fetus, and epithelial cells and meconium are accumulated in it, causing a progressive increase of its echogenicity compared to the allantoic liquid [ 43 ]. As confirmed by the present study, the difference in echogenicity between these two liquids reaches the highest level in the last 20 days of pregnancy because of the increase in the number of echogenic particles in the amniotic fluid. The authors hypothesize that these observations could be used to determine the approximate date of birth. Echogenic particles may indicate pathology and fetal stress when associated with infective debris, however, increased fluid echogenicity is not always predictive of pathology [ 21 ]. In all pregnancies evaluated in the present study, no changes in the allantoic fluid were observed throughout the gestation period. The results of the present study agree with recently published data by Ivancic et al. (2020) and provide further support for the newly established reference ranges [ 21 ].

Fetal position is another aspect to evaluate throughout gestation. In fact, keeping both the CL and the fetus in the same scan, it is possible to evaluate how, during the last three months of pregnancy, the relative topographical position of the head to the CL of the fetus is related to a podalic presentation at birth, which is the normal condition in this species (93.75% of cases). On the contrary, when the tail of the fetus is topographically related to the CL in the same image, it is related to a cephalic birth (6.25%). It is known that a cetacean fetus can change its position in the uterus during pregnancy, but usually moves into a tail-first position by the last months [ 36 , 44 ]. Head presentation of a fetus is reported for several delphinid species, and is thought to be an adaptation to the pregnancy and delivery in the aquatic environment [ 19 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 ]. It is repeatedly observed under human care—the rate of cephalic delivery was found to be 7% in killer whales ( Orcinus orca ) and 1.2% in bottlenose dolphins [ 19 ]. The labor of eight captive finless porpoises ( Neophocaena asiaeorientalis asiaeorientalis and Neophocaena asiaeorientalis sunameri ) were described by Deng et al. in 2019. The duration of parturition and the time of particular events in the parturition process were recorded for both podalic and cephalic births. Cephalic births were shorter than podalic births, and the calf position at birth did not seem to have a negative effect on its survival [ 47 ]. Successful cephalic delivery in a bottlenose dolphin under human care is described in detail by Essapian (1963)—stage 2 of the parturition lasted 22 min [ 49 ]. The result corresponds to that of the present study; in fact, the cephalic birth mentioned here also had a duration of 22 min. Even if it is indicated as a complicating factor, such cases are not referred to as pathologies [ 49 ]. In the wild, head presentation of a fetus was observed in a stranded dead white-beaked dolphin ( Lagenorhynchus albirostris ) [ 50 ]; it had ruptured the uterine wall, and thus the head presentation could be a cause of both dystocia and maternal death [ 50 ]. Numerous cases of cephalic delivery have been consistently reported for belugas ( Delphinapterus leucas ) in both nature and under human care; a rate of head-first delivery in captive belugas of 14% has been reported [ 51 , 52 , 53 ]. Head presentation seems to be more widespread in belugas than in any cetacean species. The cephalic presentation of a fetus in cetaceans is not a pathology but a natural variation. This idea is also supported by the documented cases of successful cephalic deliveries and by the occurrence of head presentations both in the wild and under human care. Nonetheless, head presentation of a fetus in a small cetacean can increase the risk of trauma or dystocia. In addition, a change of presentation at an advanced stage can be a pathology, such as that described by Baker and Martin in 1992 [ 54 ]. To the authors’ knowledge, the present study reports the first bottlenose dolphin cephalic presentation documented by US. An accurate and early ultrasound diagnosis of the presentation at delivery can help the clinician to adapt the intervention protocol to the needs of the case and, thus, minimize the risk of reproductive failure. The results of the present study reinforce the importance of monitoring health and fetal vitality throughout the duration of pregnancy and at the time of delivery by ultrasound.

In spite of the advantages provided by ultrasonographic surveys of dolphins, the procedure has some limitations compared to the same examination carried out in species commonly investigated in clinical practice [ 1 , 2 ]:

• (1) it must be conducted by an expert operator;
• (2) it depends on the features of the device;
• (3) animals must be trained for the voluntary medical behavior;
• (4) the animals must remain in water, which may not be safe for the instrumentation;
• (5) the external environment (and the light level, in particular) negatively affects results.

However, the difficulties listed above can be overcome, given the value of the information that can be gained, as the methods have been successfully applied to both under human care and wild dolphins.

5. Conclusions

This study adds further findings to the ultrasonographic monitoring protocol of bottlenose dolphin pregnancy. On the basis of the review of the literature, this is the first study that describes the sonographic data of bottlenose dolphin organogenesis and their correlation with the stage of pregnancy. As described in other species [ 40 ], these data could be used to estimate the gestational period in the dolphin in the absence of further information (such as measurements that allow derivation of linear growth diagrams, or a known ovulation date). These findings may be useful for investigations of stranding dolphins, providing data on prenatal development. These data are otherwise difficult to establish in wild cetaceans, as the precise time intervals of such developments and any distinctive growth trajectories in most cetacean species are basically unknown [ 34 , 35 , 36 , 37 , 38 , 39 ]. Furthermore, this is the first report that describes by ultrasonography the cephalic presentation of the calf at birth, according to its position within the uterus. The results of the present study reinforce the importance of monitoring health and fetal vitality throughout the duration of pregnancy and at the time of delivery by ultrasound. Reproductive success is vital in sustaining cetacean populations, and the systematic use of ultrasound for pregnancy monitoring provides a useful tool for assessing reproductive success, including for free-ranging dolphins. During capture–release health assessments, it is possible through application of diagnostic ultrasound to evaluate fetal development and viability, estimate gestational age, and measure anatomical structures [ 16 ]. This wild population conservation approach benefits from the findings of studies of the population of bottlenose dolphins under human care. Deviations from the normal findings during pregnancy could be related to the alteration of the health status and the well-being of the fetus or the mother, and, if detected sufficiently early, could result in timely therapeutic intervention for animals under human care. Thus, findings related to a reproductive failure in the wild may also be elucidated. However, further investigation will be necessary, carried out with a greater number of subjects, in order to validate the results obtained and to apply these diagnostic methods to other cetacean species.

Acknowledgments

We would like to thank the University of Perugia, Faculty of Veterinary Medicine (Dipartimento di Medicina Veterinaria, Università di Perugia, 06124, Perugia, Italy) for their support and for making this study possible. We are especially grateful to all of the staff of veterinarians and trainers who dedicate themselves daily to dolphin welfare. Their dedication and teamwork make medical behavior, investigation, and conservation projects possible.

Author Contributions

Conceptualization, P.S., L.F., F.G., A.T., A.P., and R.O.; data curation, R.M.; formal analysis, P.S., F.G., and L.F.; methodology, P.S., F.G., and R.O.; supervision, P.S. and L.F.; writing—original draft, L.F.; writing—review and editing, P.S., L.F., F.G., R.M., A.T., A.P., and R.O. All authors have read and agreed to the published version of the manuscript.

This research received no external funding.

Conflicts of Interest

The authors declare no conflict of interest.