1. Departments of Obstetrics and Gynecology and Urology, Loyola University Medical Center, Maywood, Illinois
2. Departments of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, Alabama
3. University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
4. Department of Obstetrics and Gynecology, Case Western University, Cleveland, Ohio
5. University of Utah, Salt Lake City, Utah
6. Department of Biostatistics, University of Michigan, Ann Arbor, Michigan
7. Obstetrics/Gynecology and Women's Health Institute, Cleveland Clinic, Cleveland, Ohio
8. Department of Obstetrics and Gynecology, Kaiser Permanente San Diego and Department of Reproductive Medicine, University of California-San Diego, San Diego, California
9. University of Texas Southwest, Dallas, Texas
10. Contraception and Reproductive Health Branch, Center for Population Research, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
11. Department of Urology, University of Michigan, Ann Arbor, Michigan