1. Developmental Endocrinology Branch (V.K.B., L.A., J.B., L.H., L.M.N., C.A.B.), Bethesda, Maryland 20892
2. Warren G. Magnuson Clinical Center Radiology Department (J.C.R., S.H.), National Institutes of Health, Bethesda, Maryland 20892
3. Division of Epidemiology, Statistics, and Prevention Research (J.T.), National Institute of Child Health and Human Development, Bethesda, Maryland 20892