1. Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
2. Department of Obstetrics and Gynecology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
3. Department of Obstetrics and Gynecology, University of Massachusetts Medical School, University of Massachusetts Memorial Medical Center, Worcester, Massachusetts
4. Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
5. Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
6. Department of Obstetrics and Gynecology, Weill Cornell Medicine, New York City, New York