1. Reproductive Endocrine Unit, Department of Medicine (N.D.S., S.N.H., S.S.S., J.E.H.), Massachusetts General Hospital, Boston, Massachusetts 02114
2. Division of Endocrinology (N.D.S.), Children’s Hospital Boston, Boston, Massachusetts 02115
3. Biostatistics Center (J.Y., H.L.), Massachusetts General Hospital, Boston, Massachusetts 02114