1. From the Departments of Obstetrics, Gynecology and Surgery (Division of Urology), and Radiology, University of South Florida, Tampa, Florida, Department of Urology, Division of Pediatric Urology, Johns Hopkins Hospital and School of Medicine, Baltimore, Maryland, and Department of Obstetrics and Gynecology and Division of Urology, Children's Memorial Hospital, Institute for Unborn Baby, Chicago, Illinois