1 Department of Obstetrics, Gynecology, and Reproductive Sciences, McGovern Medical School at The University of Texas Health Science Center, Houston, TX.
2 Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, 800 Spruce St., 2 Pine E., Philadelphia, PA 19107-6192. Electronic address: beth.pineles@pennmedicine.upenn.edu.