1. Division of Maternal-Fetal Medicine, the Departments of Obstetrics and Gynecology, The University of Rochester School of Medicine & Dentistry, Rochester, New York; Perinatology Research Branch, Intramural Division, NICHD, Department of Obstetrics and Gynecology, 3PHC, Georgetown University Medical Center, 3800 Res ersoir Road, NW7, Washington, DC 20007.
2. Division of Maternal-Fetal Medicine, the Departments of Obstetrics and Gynecology, The University of Rochester School of Medicine & Dentistry, Rochester, New York.