Omphalocele

An omphalocele is a birth defect involving an opening in the central portion of the fetal belly (abdomen) that allows the fetal intestines, stomach, and liver to protrude from the abdomen through the umbilical cord. The organs are still covered and protected by a thin, translucent membrane. 

An omphalocele is often diagnosed during a routine pregnancy ultrasound around 20 weeks but can sometimes be detected earlier in the first trimester. 

In some cases, a blood test collected between 15 and 20 weeks of pregnancy called the maternal serum alpha-fetoprotein test (MSAFP) may be increased. This suggests that there could be an abnormal opening in the fetal abdomen. If this occurs, your provider will recommend additional testing to better understand the findings.

Omphalocele occurs in about 1 out of every 5,000 babies. Although this condition is rare, our team of specialists at UCLA has extensive experience caring for families affected by this condition.

Omphalocele occurs when the wall of the abdomen does not form normally, but the exact cause is not fully understood. There are no proven links between medicines, chemicals, or other exposures during pregnancy with omphalocele. Some potential risk factors that may increase the risk for omphalocele include: older maternal age, multiple gestation (twin pregnancy), maternal obesity, and alcohol or tobacco use before or during pregnancy. 

No specific genetic abnormality has been identified to cause omphalocele. However, omphalocele is commonly associated with genetic syndromes, meaning a genetic abnormality that results in multiple birth defects. These include trisomy 21, trisomy 13, trisomy 18, and Beckwith-Wiedemann syndrome. 

The possible complications depend on several factors:

• Whether the fetus has other birth defects, such as heart problems or underdeveloped lungs
• The size of the omphalocele
• Whether there are genetic abnormalities

About 70% of fetuses diagnosed with an omphalocele during pregnancy also have another birth defect or a genetic condition. These additional complications often play the biggest role in the treatment plan and outcome. Your care team will carefully look for these associated conditions and guide you through what they mean for your pregnancy.

Evaluation during pregnancy begins with detailed ultrasound imaging to carefully assess the fetus and look for other birth defects or genetic conditions. Your doctor may recommend a special ultrasound of the fetal heart, called a fetal echocardiogram. Your doctor may also offer diagnostic genetic testing, such as amniocentesis (a procedure where a small amount of fluid around the fetus is sampled to look at chromosomes and genes).

Larger omphaloceles can affect lung growth (called pulmonary hypoplasia). To better evaluate lung development, your doctor may recommend an MRI to better evaluate the development of the lungs.

Babies with an omphalocele cannot be treated during pregnancy. Treatment takes place after birth and often involves surgery. Our UCLA Health team of specialists can provide counseling during pregnancy and the surgical care your baby needs after delivery.

Once a diagnosis of omphalocele is made, your care team will meet with you to talk about your baby’s condition, the rest of your pregnancy, and your delivery options. You may have more frequent ultrasounds during the remaining weeks of your pregnancy to monitor your baby’s health before delivery. Delivery is generally recommended at term (between 37-39 weeks) to allow for optimal growth of the baby. This may vary based on the presence of other complications. The mode of delivery (vaginal or cesarean) will be determined based on the size and abdominal organs present within the omphalocele. 

Please know that at UCLA Health, we have experts to care for both you and your baby during pregnancy and after delivery that include high-risk obstetrics, neonatology and pediatric surgery. Your team will also include additional specialists such as lactation and child life specialists to ensure a holistic, person-centered experience.

After your delivery, your baby will be transferred to the neonatal intensive care unit (NICU) where specialized doctors and nurses will provide care for your baby. A pediatric surgeon will examine your baby to determine what type of procedure is needed. 

How your child’s omphalocele is treated depends on several factors, including the gestational age at delivery, the size of the omphalocele, and whether there are other birth defects or genetic problems present. Each case is different and some don’t require staged repair. Typically, for smaller omphaloceles, surgery may be done soon after birth to move the organs back into the abdomen and close the defect. For larger, more complicated omphaloceles, the repair may be delayed for months. Waiting allows the abdomen time to expand and the baby to grow stronger before the repair is completed.  When repair is delayed, the omphalocele is covered with a dressing that can be applied and changed by parents.

It is common for feeding to be delayed because the bowels are slow to work after repair of the defect. During this time, babies receive IV nutrition until they can achieve full feeds. 

Depending on the specific circumstances, additional operations may be required to place a feeding tube in the stomach and/or place a special long-term catheter to provide IV nutrition.  The length of stay for more complicated cases can be quite long (several months).

You and your baby will be cared for by expert specialists in maternal fetal medicine, pediatric surgery, clinical genetics, nursing, lactation specialists, social workers, mental health specialists, child life specialists, neonatologists and the neonatal intensive care unit (NICU).

Your UCLA Health care team will support the options you have in your health care. When a pregnancy is diagnosed with fetal omphalocele, this does not mean that you will require a cesarean section. Depending on your unique situation, your care team will discuss whether you can deliver your baby vaginally or if a cesarean section will be required.

The chance of an omphalocele happening again depends on whether there is an underlying genetic cause. When the omphalocele happens by itself (without other genetic problems), the chance of omphalocele happening in future pregnancy is less than 1%. We offer genetic counseling resources where you can discuss this in detail.