1. Departments of Obstetrics and Gynecology and Pharmacology, Yale University School of Medicine, New Haven, Connecticut; Department of Obstetries and Gynecology, Nanfang Hospital, The First Military Medical University, Guangzhou, China
2. Departments of Obstetrics and Gynecology and Pharmacology, Yale University School of Medicine, New Haven, Connecticut; Department of Obstetries and Gynecology, Nanfang Hospital, The First Military Medical University, Guangzhou, China; Department of Obstetrics and Gynecology, Yale University School of Medicine, P.O. Box 208063, 333 Cedar St., FMB 301, New Haven, CT 06520-8063