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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).

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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.

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• Pregnancy week by week
• Fetal presentation before birth

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

, MD, Children's Hospital of Philadelphia

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Abnormal fetal lie or presentation may occur due to fetal size, fetal anomalies, uterine structural abnormalities, multiple gestation, or other factors. Diagnosis is by examination or ultrasonography. Management is with physical maneuvers to reposition the fetus, operative vaginal delivery Operative Vaginal Delivery Operative vaginal delivery involves application of forceps or a vacuum extractor to the fetal head to assist during the second stage of labor and facilitate delivery. Indications for forceps... read more , or cesarean delivery Cesarean Delivery Cesarean delivery is surgical delivery by incision into the uterus. The rate of cesarean delivery was 32% in the United States in 2021 (see March of Dimes: Delivery Method). The rate has fluctuated... read more .

Terms that describe the fetus in relation to the uterus, cervix, and maternal pelvis are

Fetal presentation: Fetal part that overlies the maternal pelvic inlet; vertex (cephalic), face, brow, breech, shoulder, funic (umbilical cord), or compound (more than one part, eg, shoulder and hand)

Fetal position: Relation of the presenting part to an anatomic axis; for transverse presentation, occiput anterior, occiput posterior, occiput transverse

Fetal lie: Relation of the fetus to the long axis of the uterus; longitudinal, oblique, or transverse

Normal fetal lie is longitudinal, normal presentation is vertex, and occiput anterior is the most common position.

Abnormal fetal lie, presentation, or position may occur with

Fetopelvic disproportion (fetus too large for the pelvic inlet)

Fetal congenital anomalies

Uterine structural abnormalities (eg, fibroids, synechiae)

Multiple gestation

Several common types of abnormal lie or presentation are discussed here.

Transverse lie

Fetal position is transverse, with the fetal long axis oblique or perpendicular rather than parallel to the maternal long axis. Transverse lie is often accompanied by shoulder presentation, which requires cesarean delivery.

Breech presentation

There are several types of breech presentation.

Frank breech: The fetal hips are flexed, and the knees extended (pike position).

Complete breech: The fetus seems to be sitting with hips and knees flexed.

Single or double footling presentation: One or both legs are completely extended and present before the buttocks.

Types of breech presentations

Breech presentation makes delivery difficult ,primarily because the presenting part is a poor dilating wedge. Having a poor dilating wedge can lead to incomplete cervical dilation, because the presenting part is narrower than the head that follows. The head, which is the part with the largest diameter, can then be trapped during delivery.

Additionally, the trapped fetal head can compress the umbilical cord if the fetal umbilicus is visible at the introitus, particularly in primiparas whose pelvic tissues have not been dilated by previous deliveries. Umbilical cord compression may cause fetal hypoxemia.

Predisposing factors for breech presentation include

Preterm labor Preterm Labor Labor (regular uterine contractions resulting in cervical change) that begins before 37 weeks gestation is considered preterm. Risk factors include prelabor rupture of membranes, uterine abnormalities... read more

Multiple gestation Multifetal Pregnancy Multifetal pregnancy is presence of > 1 fetus in the uterus. Multifetal (multiple) pregnancy occurs in up to 1 of 30 deliveries. Risk factors for multiple pregnancy include Ovarian stimulation... read more

Uterine abnormalities

Fetal anomalies

If delivery is vaginal, breech presentation may increase risk of

Umbilical cord prolapse

Perinatal death

It is best to detect abnormal fetal lie or presentation before delivery. During routine prenatal care, clinicians assess fetal lie and presentation with physical examination in the late third trimester. Ultrasonography can also be done. If breech presentation is detected, external cephalic version can sometimes move the fetus to vertex presentation before labor, usually at 37 or 38 weeks. This technique involves gently pressing on the maternal abdomen to reposition the fetus. A dose of a short-acting tocolytic ( terbutaline 0.25 mg subcutaneously) may help. The success rate is about 50 to 75%. For persistent abnormal lie or presentation, cesarean delivery is usually done at 39 weeks or when the woman presents in labor.

Face or brow presentation

In face presentation, the head is hyperextended, and position is designated by the position of the chin (mentum). When the chin is posterior, the head is less likely to rotate and less likely to deliver vaginally, necessitating cesarean delivery.

Brow presentation usually converts spontaneously to vertex or face presentation.

Occiput posterior position

The most common abnormal position is occiput posterior.

The fetal neck is usually somewhat deflexed; thus, a larger diameter of the head must pass through the pelvis.

Progress may arrest in the second phase of labor. Operative vaginal delivery Operative Vaginal Delivery Operative vaginal delivery involves application of forceps or a vacuum extractor to the fetal head to assist during the second stage of labor and facilitate delivery. Indications for forceps... read more or cesarean delivery Cesarean Delivery Cesarean delivery is surgical delivery by incision into the uterus. The rate of cesarean delivery was 32% in the United States in 2021 (see March of Dimes: Delivery Method). The rate has fluctuated... read more is often required.

Position and Presentation of the Fetus

If a fetus is in the occiput posterior position, operative vaginal delivery or cesarean delivery is often required.

In breech presentation, the presenting part is a poor dilating wedge, which can cause the head to be trapped during delivery, often compressing the umbilical cord.

For breech presentation, usually do cesarean delivery at 39 weeks or during labor, but external cephalic version is sometimes successful before labor, usually at 37 or 38 weeks.

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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.

Related MedlinePlus Health Topics

• Childbirth Problems

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Chapter 15:  Abnormal Cephalic Presentations

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Malpresentations.

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The fetus enters the pelvis in a cephalic presentation approximately 95 percent to 96 percent of the time. In these cephalic presentations, the occiput may be in the persistent transverse or posterior positions. In about 3 percent to 4 percent of pregnancies, there is a breech-presenting fetus (see Chapter 25 ). In the remaining 1 percent, the fetus may be either in a transverse or oblique lie (see Chapter 26 ), or the head may be extended with the face or brow presenting.

Predisposing Factors

Maternal and uterine factors.

Contracted pelvis: This is the most common and important factor

Pendulous maternal abdomen: If the uterus and fetus are allowed to fall forward, there may be difficulty in engagement

Neoplasms: Uterine fibromyomas or ovarian cysts can block the entry to the pelvis

Uterine anomalies: In a bicornuate uterus, the nonpregnant horn may obstruct labor in the pregnant one

Abnormalities of placental size or location: Conditions such as placenta previa are associated with unfavorable positions of the fetus

High parity

Fetal Factors

Errors in fetal polarity, such as breech presentation and transverse lie

Abnormal internal rotation: The occiput rotates posteriorly or fails to rotate at all

Fetal attitude: Extension in place of normal flexion

Multiple pregnancy

Fetal anomalies, including hydrocephaly and anencephaly

Polyhydramnios: An excessive amount of amniotic fluid allows the baby freedom of activity, and he or she may assume abnormal positions

Prematurity

Placenta and Membranes

Placenta previa

Cornual implantation

Premature rupture of membranes

Effects of Malpresentations

Effects on labor.

The less symmetrical adaptation of the presenting part to the cervix and to the pelvis plays a part in reducing the efficiency of labor.

The incidence of fetopelvic disproportion is higher

Inefficient uterine action is common. The contractions tend to be weak and irregular

Prolonged labor is seen frequently

Pathologic retraction rings can develop, and rupture of the lower uterine segment may be the end result

The cervix often dilates slowly and incompletely

The presenting part stays high

Premature rupture of the membranes occurs often

The need for operative delivery is increased

Effects on the Mother

Because greater uterine and intraabdominal muscular effort is required and because labor is often prolonged, maternal exhaustion is common

There is more stretching of the perineum and soft parts, and there are more lacerations

Tears of the uterus, cervix, and vagina

Uterine atony from prolonged labor

Early rupture of the membranes

Excessive blood loss

Tissue damage

Frequent rectal and vaginal examinations

Prolonged labor

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Undiagnosed Uterine Didelphys in a Multiparous Somali Woman with Two Previous Cesarean Sections

1 Obstetrics and Gynecology Department, Somalia Mogadishu Turkey Recep Tayyip Erdogan Training and Research Hospital, Mogadishu, Somalia

Safia Ahmed Hussein

Uterine didelphys (UD) develops from failure of fusion of the paired Müllerian ducts, resulting in two noncommunicating uteri. We present a 31-year-old pregnant woman whose UD anomaly had not been detected during two previous cesarean sections and her presentation to a health-care clinic for her fifth pregnancy.

Case Presentation

She was referred to our obstetrics clinic due to suspicion of abdominal pregnancy and a complaint of severe lower abdominal pain. On ultrasonography, UD was detected with two adjacent uteri, one of which was empty and the other with a fetus of approximately 1100 g at 28 weeks and 1 day of gestational age. Magnetic resonance imaging confirmed the presence of UD. Due to severe lower abdominal pain of the patient and severe oligohydramnios of the fetus, emergency cesarean section was performed, and a 980 g male baby was delivered.

This case exemplifies how difficult life is for women living in an underdeveloped and resource-limited country like Somalia.

Introduction

Uterine didelphys (UD) develops from failure of fusion of the paired Müllerian ducts, resulting in two uterine horns and creating two noncommunicating cavities. Each uterine cavity has a fallopian tube, but may or may not have its own cervix. Of all Müllerian anomalies, UD comprises 8%–10%, and has an incidence of one in 3000 women. A single vaginal canal is rarely encountered. 1–4

UD is known to be accompanied by renal anomalies, which are often unilateral and right-sided, 15%–25% of the time. 1–4 Although this anomaly can be detected by ultrasound examination at any trimester of pregnancy, this may not occur in underdeveloped countries where diagnostic tools are unavailable or extremely limited. Somali is an example of one such countries where many pregnant women may not have the chance to see an obstetrician until delivery or have to give birth at home, even without the help of a midwife.

A 31-year-old pregnant woman (gravida 5, para 4) was referred to the obstetrics department of a tertiary health-care center in Mogadishu, Somalia because of a suspected abdominal pregnancy and a 2-day history of severe lower abdominal pain. On the morning of presentation, she had visited a health-care clinic with a complaint of severe lower abdominal pain, where she had her first ultrasound examination during pregnancy. An initial diagnosis of abdominal pregnancy was made. At the current presentation, she did not remember her last menstrual bleeding and did not report any problems with her four prior full-term pregnancies, which ended up with normal vaginal deliveries in the first two and cesarean sections for the latter two. No information could be elicited from the patient concerning her previous cesarean sections.

Physical examination was unremarkable except for abdominal pain on palpation. Uterine contractions were present on a nonstress test. Pelvic examination showed a soft and 2 cm dilated cervix. Transabdominal ultrasonography revealed two adjacent uteri, one of which was empty ( Figure 1 , arrow) and the other bearing a fetus of approximately 1100 g at 28 weeks and 1 day of gestational age, with cephalic presentation and severe oligohydramnios ( Figure 1 ). Magnetic resonance imaging substantiated ultrasonographic findings of the two uteri, with a single fetus in the left one having cephalic presentation, findings consistent with intrauterine pregnancy ( Figure 2 , arrow). A diagnosis of UD was made.

Transabdominal ultrasound showing two adjacent noncommunicating uteri (arrows), one of which is empty and the other is bearing a fetus.

Magnetic resonance image showing two adjacent noncommunicating uteri (arrows), one of which is empty and the other is bearing a fetus.

On the same day of presentation and after administration of betamethasone, due to the very severe lower abdominal pain of the patient and severe oligohydramnios of the fetus, the patient underwent emergency cesarean section under general anesthesia, and a 980 g male baby was delivered. His 1- and 5-min APGAR scores were 4 and 5, respectively. The newborn was transferred to the newborn intensive care unit for postnatal care. The mother had an uneventful postoperative course and was discharged home on the second postoperative day in very good condition. Given her background of poor health-seeking behavior and the three cesarean sections she had undergone, the patient was counseled about appropriate ways of contraception other than a uterine device.

Although UD can be diagnosed with ultrasonography at any time, particularly during pregnancy, it may easily go unnoticed in underdeveloped countries like Somalia, where women have been particularly unlucky amid a host of adverse conditions, including lack of security throughout the country because of ongoing civil war, resource-limited health-care facilities, and transportation difficulties, as well as poverty. This case also emphasizes the shortcomings of the health-care system, particularly with regard to obstetric policies and services and the training and experience of obstetricians.

The current case had a history of two deliveries with cesarean section, yet her anomaly had been missed. Moreover, at the time of presentation to another clinic with severe lower abdominal pain, the anomaly was not suspected on ultrasonography and the clinical picture was mistaken for abdominal pregnancy. Documentation of UD has mainly been reported in women before pregnancy or during examinations for their first pregnancy. 1 , 5 Conversely, as with our case, reports of UD have been rare in women whose diagnosis has been missed before or during previous pregnancies and cesarean section deliveries. 6

This case exemplifies how difficult life is for women living in an underdeveloped and resource-limited country like Somalia. Apart from the UD anomaly being undiagnosed, many women experience their pregnancies without even seeing an obstetrician and deliver their babies at home without medical support. Apart from providing the necessary education and training to all parties concerned, ie, patients and obstetricians, it should be noted that a great majority of problems encountered in underdeveloped countries are of international nature and thus cannot be solved without international cooperation and collaboration.

Informed consent was obtained from the patient for the publication of her case.

Institutional Approval

Institutional review board approval is not required by our hospital if identifiable information is not used in the case report.

The authors report no conflicts of interest in this work.

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Developing Novel Genomic Risk Stratification Models in Soft Tissue and Uterine Leiomyosarcoma

Clin Cancer Res 2024;XX:XX–XX

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Josephine K. Dermawan , Sarah Chiang , Samuel Singer , Bhumika Jadeja , Martee L. Hensley , William D. Tap , Sujana Movva , Robert G. Maki , Cristina R. Antonescu; Developing Novel Genomic Risk Stratification Models in Soft Tissue and Uterine Leiomyosarcoma. Clin Cancer Res 2024; https://doi.org/10.1158/1078-0432.CCR-24-0148

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Leiomyosarcomas (LMS) are clinically and molecularly heterogeneous tumors. Despite recent large-scale genomic studies, current LMS risk stratification is not informed by molecular alterations. We propose a clinically applicable genomic risk stratification model.

We performed comprehensive genomic profiling in a cohort of 195 soft tissue LMS (STLMS), 151 primary at presentation, and a control group of 238 uterine LMS (ULMS), 177 primary at presentation, with at least 1-year follow-up.

In STLMS, French Federation of Cancer Centers (FNCLCC) grade but not tumor size predicted progression-free survival (PFS) or disease-specific survival (DSS). In contrast, in ULMS, tumor size, mitotic rate, and necrosis were associated with inferior PFS and DSS. In STLMS, a 3-tier genomic risk stratification performed well for DSS: high risk: co-occurrence of RB1 mutation and chr12q deletion (del12q)/ ATRX mutation; intermediate risk: presence of RB1 mutation, ATRX mutation, or del12q; low risk: lack of any of these three alterations. The ability of RB1 and ATRX alterations to stratify STLMS was validated in an external AACR GENIE cohort. In ULMS, a 3-tier genomic risk stratification was significant for both PFS and DSS: high risk: concurrent TP53 mutation and chr20q amplification/ ATRX mutations; intermediate risk: presence of TP53 mutation, ATRX mutation, or amp20q; low risk: lack of any of these three alterations. Longitudinal sequencing showed that most molecular alterations were early clonal events that persisted during disease progression.

Compared with traditional clinicopathologic models, genomic risk stratification demonstrates superior prediction of clinical outcome in STLMS and is comparable in ULMS.

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Supplementary data.

Immunohistochemical antibodies

Supplementary Table S2. Clinicopathologic summary of uterine leiomyosarcoma (ULMS)

Supplementary Figure S1. A. Lollipop plots depicting the distribution of point mutations in TP53, RB1 and ATRX in STLMS and ULMS. B-C. Oncoprints in STLMS (B) and ULMS (C) depicting the distribution of recurrent genetic alterations in primary versus metastatic samples (unpaired).

Supplementary Figure S2. MSKCC STLMS cohort. Genomic variables (gene level point mutations and copy number changes and chromosomal arm level changes) are input into the OncoCast model using the elastic net (“ENET”) approach, with outcome being overall survival. Variable importance is assigned and visualized in a plot by selection frequency (the event frequency of that feature in the data) and Cox proportional hazard ratios. Dotted lines indicate threshold of 0.55 selection frequency and hazard ratio of 1.

Supplementary Figure S3. Overall survival (OS) for 195 STLMS patients from the MSK cohort stratified by in low-, intermediate-, and high-risk genomic groups represented by Kaplan-Meier curves.

Supplementary Figure S4. Disease-specific survival (DSS) for STLMS patients (primary at presentation) from the MSK cohort stratified by tumor size represented by Kaplan-Meier curves. Bottom: Alluvial diagram comparing tumor size versus genomic risk groups in STLMS.

Supplementary Figure S5. A. Forest plot depicting univariate Cox regression analysis for clinicopathologic and genomic risk variables for DSS in STLMS patients. B. Forest plot depicting multivariate Cox regression analysis comparing mitotic rate and necrosis with high genomic risk group for DSS in STLMS patients.

Supplementary Figure S6. Oncoprint depicting frequency of TP53, RB1, ATRX, PTEN, and MAP2K4 in the AACR GENIE STLMS cohort.

Supplementary Figure S7. Modified 3-tier genomic risk stratification in STLMS cohort. DSS represented by Kaplan-Meier curves.

Supplementary Figure S8. STLMS genomic risk stratification for progression-free survival (PFS). A, A 2-tier genomic risk group is proposed for PFS. PFS for 151 patients with primary STLMS from the MSK cohort with low- and high-risk genomic groups is represented by Kaplan-Meier curves.

Supplementary Figure S9. MSKCC ULMS cohort. Genomic variables (gene level point mutations and copy number changes and chromosomal arm level changes) are input into the OncoCast model using the elastic net (“ENET”) approach, with outcome being overall survival. Variable importance is assigned and visualized in a plot by selection frequency (the event frequency of that feature in the data) and Cox proportional hazard ratios. Dotted lines indicate threshold of 0.50 selection frequency and hazard ratio of 1.

Supplementary Figure S10. ULMS genomic risk stratification for disease-specific survival (DSS). A 3-tier genomic risk group is proposed for DSS. DSS for 238 ULMS patients from the MSK cohort in low, intermediate, and high-risk genomic groups is represented by Kaplan-Meier curves (global log-rank P and Benjamin-Hochberg adjusted P-values by pairwise analysis).

Supplementary Figure S11. ULMS genomic risk stratification for progression-free survival (PFS). A, A 3-tier genomic risk group is proposed for PFS. PFS for 238 patients with primary ULMS from the MSK cohort with low-, intermediate- and high-risk genomic groups [co-occurrence of TP53 and ATRX mutations or co-occurrence of TP53 mutation and chr20q amplification (amp20q); intermediate risk – presence of any of the following: TP53 mutation, ATRX mutation or amp20q; low risk – lack of any of these three alterations], as well as stratification by tumor size (B), mitotic rate (C), and necrosis (D) are represented by Kaplan-Meier curves.

Supplementary Figure S12. A. Forest plot depicting univariate Cox regression analysis for clinicopathologic and genomic risk variables for DSS in ULMS patients. B. Forest plot depicting multivariate Cox regression analysis comparing tumor size, mitotic rate and necrosis with high genomic risk group for DSS in ULMS patients.

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