1. Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine and Perinatal Research, The University of Texas Medical Branch at Galveston, 301 University Blvd., MRB, Room 11.138, Galveston, TX, USA
2. Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Vermont College of Medicine, 792 College Parkway, Fanny Allen Campus, Suite 101, Colchester, Burlington, VT, USA
3. Department of Obstetrics and Gynecology, Wayne State University, Perinatal Research Branch, NICHD, Detroit, MI, USA
4. Department of Reproductive Biology and Obstetrics and Gynecology, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, USA
5. Department of Obstetrics and Gynecology, Medical Center Boulevard, Wake Forest School of Medicine, Winston-Salem, NC, USA