1. From the Division of Maternal Fetal Medicine and Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland (R.M.B.); and Division of Maternal Fetal Medicine (B.B.F.), Laboratory of Genital Tract Biology (H.Y.D., H.S.Y., R.N.F.), and Department of Obstetrics, Gynecology, and Reproductive Biology (S.R.E.), Brigham and Women’s Hospital, Harvard Medical School, Boston, MA.