1. Department of Obstetrics and Gynecology, Women and Infants Hospital, Warren Alpert Medical School at Brown University, Providence, Rhode Island, USA.
2. Department of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA.
3. Department of Emergency Medicine, Warren Alpert Medical School at Brown University, Providence, Rhode Island, USA.
4. Department of Women's Health, Dell Medical School, University of Texas at Austin, Austin, Texas, USA.