The purpose of this study was to review antenatal sonographic findings in children born with persistent cloaca.Infants (n =145) with persistent cloaca followed at a center for colorectal congenital anomalies were identified by a retrospective chart review. Fifty female infants with a persistent cloaca met inclusion criteria and had prenatal records and imaging studies available for review. Sonographic data were retrospectively abstracted from charts.Anomalies were detected in 27 of 50 cases (54%). A correct antenatal diagnosis of persistent cloaca occurred in 3 of 50 (6%). Common findings misinterpreted on antenatal sonography include urinary tract anomalies, dilated bowel, and a cystic pelvic mass (representing hydrocolpos).Antenatal diagnosis of persistent cloaca is difficult. Persistent cloaca should be considered in the differential diagnosis if urinary tract malformations, dilated bowel loops, or cystic pelvic masses are visualized by prenatal diagnosis.