1. Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, MD
2. Department of Family and Preventive Medicine, University of Utah Health Sciences Center, Salt Lake City, UT
3. Department of Epidemiology and Environmental Health, University at Buffalo, Buffalo, NY
4. Program of Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD