The antenatal sonographic visualization of cloacal dysgenesis.

Hydronephrosis associated with a septated cystic structure in the fetal pelvis in the absence of an otherwise identifiable fetal bladder should alert the sonographer to the possibility of a persistent cloaca. Problems associated with compromised urinary tract drainage and the associated oligohydramnios occurring early in gestation as well as frequent association of anomalies with other organ systems must be addressed. Squamous epithelia in fetal bladder aspirate is further supportive evidence for the diagnosis.