1 Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO.
2 Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO.
3 Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill, Chapel Hill, NC.
4 Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO; Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO.
5 Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO.
6 Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO; Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO. Electronic address: nrahghuraman@wustl.edu.