1. Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, Pennsylvania
2. Department of Obstetrics and Gynecology, Duke University, Durham
3. Social, Statistical and Environmental Sciences Group, RTI International, Research Triangle Park, North Carolina
4. Department of Obstetrics, Gynecology & Reproductive Sciences, University of California San Diego, La Jolla, California
5. Department of Obstetrics and Gynecology, Brown University, Providence, Rhode Island
6. Department of Obstetrics and Gynecology, University of New Mexico, Albuquerque, New Mexico
7. Department of Women's Health, Dell Medical School, University of Texas, Austin, Texas
8. Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, Alabama
9. Obstetrics, Gynecology and Women's Health Institute, Cleveland Clinic, Cleveland, Ohio
10. Department of Urology, University of Pittsburgh, Pittsburgh, Pennsylvania
11. Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland