1. Department of Medicine (V.M., P.D.C., R.S.S., C.W.), Division of Endocrinology, Harbor-UCLA Medical Center and Los Angeles Biomedical Research Institute, Torrance, California 90509
2. Department of Medicine (J.K.A., W.J.B., S.T.P.), University of Washington, Seattle, Washington 98195
3. Center for Biomedical Research (R.S.-W., N.K., Y.-Y.T.), Population Council, New York, New York 10021
4. Contraception and Reproductive Health Branch (D.B.), National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20852