Facts about Omphalocele

Pronounced uhm-fa-lo-seal

Omphalocele, also known as exomphalos, is a birth defect of the abdominal (belly) wall. The infant’s intestines, liver, or other organs stick outside of the belly through the belly button. The organs are covered in a thin, nearly transparent sac that hardly ever is open or broken. 

As the baby develops during weeks six through ten of pregnancy, the intestines get longer and push out from the belly into the umbilical cord. By the eleventh week of pregnancy, the intestines normally go back into the belly. If this does not happen, an omphalocele occurs.

The omphalocele can be small, with only some of the intestines outside of the belly, or it can be large, with many organs outside of the belly. Because some or all of the abdominal (belly) organs are outside of the body, babies born with an omphalocele can have other problems as well. The abdominal cavity, the space in the body that holds these organs, might not grow to its normal size.  Also, infection is a concern, especially if the sac around the organs is broken. Sometimes, an organ might become pinched or twisted, and loss of blood flow might damage the organ. 

The Centers for Disease Control and Prevention (CDC) estimates that each year about 775 babies in the United States are born with an omphalocele.¹ In other words, about 1 out of every 5,386 babies born in the United States each year is born with an omphalocele. Many babies born with an omphalocele also have other birth defects, such as heart defects, neural tube defects, and chromosomal abnormalities.²

 

Causes and Risk Factors

Like many families affected by birth defects, we at CDC want to find out what causes them. Understanding factors that can increase the chance of having a baby with a birth defect will help us learn more about the causes. Currently, we are working on one of the largest U.S. studies―the National Birth Defects Prevention Study―to understand the causes of and risk factors for birth defects. This study is looking at many possible risk factors for birth defects, such as omphalocele.

Recently, CDC researchers have reported important findings about some factors that can affect the risk of having a baby with an omphalocele:

• Alcohol and tobacco: Women who consumed alcohol or were heavy smokers (more than 1 pack a day) were more likely to have a baby with omphalocele.³
  
  
• Certain medications: Women who used selective serotonin-reuptake inhibitors (SSRIs) during pregnancy were more likely to have a baby with an omphalocele.⁴
  
  
• Obesity: Women who were obese or overweight before pregnancy were more likely to have a baby with an omphalocele.⁵

CDC continues to study birth defects such as omphaloceles and how to prevent them. If you consume alcohol or smoke cigarettes, take medications, or are obese, and you are pregnant or thinking about getting pregnant, talk with your doctor about ways to increase your chances of having a healthy baby.

 

Diagnosis

An omphalocele can be diagnosed during pregnancy or after a baby is born.

During Pregnancy

During pregnancy, there are screening tests (prenatal tests) to check for birth defects and other conditions. An omphalocele might result in an abnormal result on a blood or serum screening test or it might be seen during an ultrasound (which creates pictures of the baby).

After a Baby Is Born

In some cases, an omphalocele might not be diagnosed until after a baby is born. An omphalocele is seen immediately at birth.

 

Treatments

Treatment for infants with an omphalocele depends on a number of factors, including

• the size of the omphalocele,
  
  
• the presence of other birth defects or chromosomal abnormalities, and
  
  
• the baby’s gestational age.

If the omphalocele is small (only some of the intestine is outside of the belly), it usually is treated with surgery soon after birth to put the intestine back into the belly and close the opening.  If the omphalocele is large (many organs outside of the belly), the repair might be done in stages.  The exposed organs might be covered with a special material, and slowly, over time, the organs will be moved back into the belly. When all the organs have been put back in the belly, the opening is closed.

 

 

References

1. Parker SE, Mai CT, Canfield MA, Rickard R, Wang Y, Meyer RE, et al; for the National Birth Defects Prevention Network. Updated national birth prevalence estimates for selected birth defects in the United States, 2004-2006. Birth Defects Res A Clin Mol Teratol. 2010 Sept 28. [Epub ahead of print]
2. Stoll C, Alembik Y, Dott B, Roth MP. Omphalocele and gastroschisis and associated malformations. Am J Med Genet A. 2008 May 15;146A(10):1280-5.
3. Bird TM, Robbins JM, Druschel C, Cleves MA, Yang S, Hobbs CA, & the National Birth Defects Prevention Study . Demographic and environmental risk factors for gastroschisis and omphalocele in the National Birth Defects Prevention Study. J Pediatr Surg, 2009;44:1546-1551.
4. Alwan S, Reefhuis J, Rasmussen SA, Olney RS, Friedman JM, & the National Birth Defects Prevention Study. Use of Selective Serotonin-Reuptake Inhibitors in Pregnancy and the Risk of Birth Defects. N Engl J Med, 2007;356:2684-92.
5. Waller DK, Shaw GM, Rasmussen SA, Hobbs CA, Canfield MA, Siega-Riz AM, Gallaway MS, Correa A, & the National Birth Defects Prevention Study. Prepregnancy obesity as a risk factor for structural birth defects. Arch Pediatr Adolesc Med, 2007;161(8):745-50.