1. Department of Obstetrics and Gynecology, University of Pennsylvania , Philadelphia, PA 19104 , USA
2. Department of Obstetrics, Gynecology, & Reproductive Sciences, Reproductive Medicine Associates (IVIRMA), Rutgers Robert Wood Johnson Medical School , New Brunswick, NJ 07920 , USA
3. Department of Biostatistics and Epidemiology, University of Pennsylvania , Philadelphia, PA 19104 , USA
4. Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Utah , Salt Lake City, UT 84132 , USA
5. Center for Reconstructive Urology and Men's Health, Departments of Surgery (Urology) and Obstetrics and Gynecology, School of Medicine, University of Utah , Salt Lake City, UT 84112 , USA
6. Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Washington , Seattle, WA 98105 , USA
7. Department of Obstetrics and Gynecology, Carver College of Medicine, University of Iowa , Iowa City, IA 52242 , USA
8. Departments of Surgery (Urology) and Human Genetics, School of Medicine, University of Utah , Salt Lake City, UT 84112 , USA
9. Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo , Buffalo, NY 14214 , USA
10. Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development , Bethesda, MD 20892 , USA