Cloacal anomaly simulating megalocystis in the first trimester.

We present a case of cloacal anomaly that simulated megalocystis in the first trimester of gestation of a female fetus. During the second trimester, repeated paracentesis was necessary to treat increasing ascites, oligohydramnios, and hydronephrosis. Our data support findings that ascites presenting with a multiloculated cystic structure on sonography during the second trimester may be typical for cloacal anomalies. Active treatment of the fetal ascites is recommended to improve the child's prospects for survival.