OEIS (Omphalocele, extrophy of bladder/cloaca, imperforate anus, spinal defects) is a rare constellation of malformations involving multiple organs in humans. It is the most serious manifestation of exstrophy-epispadias sequence. The exact aetiology of this condition is not known. It is sporadic but genetic associations have also been hypothesised. It results from defective blastogenesis leading to improper closure of anterior abdominal wall and defective development of cloacae and urogenital septum. Incidence ranges from 1 in 200000 to 1 in 400000. Prenatal diagnosis of OEIS complex can be done by anomaly scan between 18 to 22 weeks of gestation. It carries a poor prognosis. Survival is nil or very less. Even if baby survives it requires multiple surgeries with many potential complications. We had an undiagnosed case of this complex presenting to us in advanced labour, but a timely ultrasound helped in the diagnosis and avoided an unnecessary caesarean section which we would have done for an elderly primigravida with breech presentation.
OEIS complex, Foetal anomaly, Anomaly scan