Approximately 1 in 5,000 babies have an omphalocele that contains bowel only. Liver herniation is also frequently associated with an underdeveloped abdominal cavity and pulmonary hypoplasia which may complicate the postnatal course. Fetuses with omphalocele are at increased risk for other malformations, most commonly cardiac and genitourinary anomalies, neural tube defects, or intestinal malrotation. Fetal karyotyping is important to rule out chromosome anomalies such as trisomy 13 or 18, in particular in fetuses with small omphaloceles. In addition, omphalocele may also be associated with several syndromes such as Beckwith-Wiedemann syndrome or Pentalogy of Cantrell.
Prognosis depends largely on the size of the defect and the presence or absence of other anomalies.
Evaluation Families coming for evaluation of a ventral wall defect to the Center for Fetal Diagnosis and Treatment will undergo a comprehensive one-day evaluation. A level II sonogram is performed to assess fetal development and detect any other structural malformations. A fetal echocardiogram rules out most cardiac malformations while an ultrafast fetal MRI is a useful adjunct to ultrasound in confirming the diagnosis, determining the extent of liver involvement, and measuring lung volumes. Following conclusion of these tests, families meet with a pediatric surgeon and an obstetrician to review all results and discuss prognosis and postnatal management approaches. Depending upon the extent and severity of associated anomalies, a family may choose to continue or end the pregnancy.