Affiliation: | 1. Motherisk Program, Hospital for Sick Children and University of Toronto, Toronto, ON, Canada;3. Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX;4. Department of Obstetrics and Gynecology, University of Pittsburgh Medical Center, Pittsburgh, PA;5. Departments of Obstetrics and Gynecology, Washington Hospital Center and Georgetown University Medical Center, Washington, DC |