Omphalocele Secondary to Spontaneous Rupture of Allantoic Cyst in the Third Trimester of Pregnancy.

Objective: We report the first case in which the onset of omphalocele was after the spontaneous rupture of an allantoic cyst. We hypothesize a causal link between the spontaneous rupture of the cyst and the herniation of the viscera. Case Presentation. A 36-year-old woman was diagnosed with an allantoic cyst during the first trimester. The allantoic cyst underwent spontaneous rupture during the 32nd week of gestation, and an omphalocele developed secondary to the cyst's rupture. Two days after birth, the peritoneum covering intestinal loops broke spontaneously and the newborn underwent successful urgent surgery.

Conclusions: This case may suggest that the relative benignity of the allantoid cysts may recommend a close ultrasound follow-up in order to identify the onset of any complications, as a late third trimester onset of omphalocele. Prenatal diagnosis of such complications may allow multidisciplinary management of the pregnancy with planned cesarean section, prenatal pediatric surgery consultation, and neonatal surgery.