Distinguishing omphalocele from pseudo-omphalocele, highlighting the ultrasonography pitfall: a case report

Omphalocele is a congenital anomaly where abdominal contents herniate through a defect in the fetal abdominal wall, covered by peritoneum and amnion. It is associated with high mortality and other anomalies. Pseudo-omphalocele is a potential pitfall in antenatal ultrasonography, where a transient bulge of abdominal contents may appear owing to factors such as a contracted uterus, placenta, or excessive transducer pressure.

This report presents two cases: one of true omphalocele in a twin pregnancy and another of pseudo-omphalocele, underscoring the importance of careful assessment. The first case involves a twin pregnancy at 12 weeks' gestation, conceived through assisted reproductive technique in a 38-year-old Nepali woman of Indo-Aryan ethnicity. During a routine check-up, one twin was diagnosed with omphalocele. Trans-abdominal fetal reduction of the anomalous twin was performed. The other twin progressed to term and was delivered via cesarean section at 39 weeks. The second case involved pseudo-omphalocele, observed at 15 weeks' 3 days of gestation in a 32-year-old Nepali woman of Tibeto-Burmese ethnicity. Initially, the fetal abdomen appeared to herniate, mimicking omphalocele. However, a repeat examination after 30 min showed no herniation or defect. Retrospective analysis revealed that the misdiagnosis occurred because the fetal abdomen was compressed between the contracted myometrium and placenta.

Accurate diagnosis of omphalocele is crucial to prevent unnecessary abortions and potential professional repercussions. We recommend repeat examination after 30 min in all cases of omphalocele to prevent misdiagnosis.