1. Departments of Obstetrics/Gynecology/Reproductive Sciences (V.A.H., J.S.B., E.D.A.), Center for Studies in Reproduction, The University of Maryland School of Medicine, Baltimore, Maryland 21201
2. Department of Physiology (R.D.K.), Center for Studies in Reproduction, The University of Maryland School of Medicine, Baltimore, Maryland 21201
3. Department of Physiological Sciences (G.J.P.), Eastern Virginia Medical School, Norfolk, Virginia 23507