Background and Aims Initially defined as a rare complication, ovarian autoamputation is increasingly reported in neonates and infants less than one year of age. Antenatal ultrasound may not always be relevant in determining long term outcome of complex ovarian cysts. A sonographically persistent ovarian cyst may be free floating in the peritoneal cavity with no connection to the pelvis, or may parasite omental or mesenteric circulation, simulating an omental or mesenteric cyst.

Methods Five patients with prenatally diagnosed cystic masses are reported. The masses were initially detected during 28, 33, 34 and 35 weeks of gestational age, with septations and dense echogenicity mimicking complex ovarian cysts. The cysts failed to resolve in all cases. Serum αFP levels were normal on date of admission in three elder cases and returned to normal in two newborns. β-hCG was within normal limits. CT or MRI studies confirmed cystic lesion with additional calcification area in two patients.

Results Laparoscopic approach revealed ovarian autoamputation in all patients with vessel resembling attachments originating from the greater omentum in two, and ileal mesenteric attachment in another. Histopathology revealed a hemorrhagic cyst with areas of infarction in four cases and locus of mature teratoma in one. Four patients were discharged within 24 hours postop.

Conclusions Radiology failed to detect torsion and autoamputation in all patients with prenatally diagnosed hypoechogenic cystic masses which failed to resolve following conservative management. The possibility of an otherwise silent ovarian autoamputation in a neonate, may necessitate laparoscopic intervention for correct diagnosis.