1. From the Departments of Obstetrics and Gynecology, University of Pittsburgh, Pittsburgh (J.M.R.); University of Cincinnati College of Medicine, Cincinnati (L.M.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (C.Y.S.) and the National Heart, Lung, and Blood Institute (G.D.P.) — both in Bethesda, MD; George Washington University Biostatistics Center, Washington, DC (E.A.T.); University of Alabama at Birmingham, Birmingham (J.C.H.); University of Texas Southwestern Medical...