1. Department of Obstetrics and Gynecology, Thomas Jefferson University Hospital, Philadelphia, PA, USA
2. Department of Obstetrics and Gynecology, Cedars-Sinai Medical Center, Division of Maternal-Fetal Medicine, 8700 Beverly Boulevard, Suite 160W, Los Angeles, CA 90046, USA
3. Department of Obstetrics and Gynecology, University of Washington Medical Center, Seattle, WA, USA
4. Department of Obstetrics and Gynecology, University of Massachusetts Medical Center, Worcester, MA, USA
5. Department of Obstetrics and Gynecology, University of British Columbia—Oak Tree Clinic, BC, Vancouver, Canada
6. Department of Obstetrics and Gynecology, Dube University Medical Center, Durham, NC, USA
7. Department of Obstetrics and Gynecology, Wake Forest University School of Medicine, Winston-Salem, NC, USA