University of Florida, College of Medicine, Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Gainesville, Florida Correspondence: Patrick Duff, MD, University of Florida, College of Medicine, Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, P.O. Box 100294, Gainesville, FL 32610–0294. E-mail: [email protected]