[1] Maimonides Hosp, Dept Obstet & Gynecol, Brooklyn, NY 11219 USA
[2] SUNY Hlth Sci Ctr, Dept Obstet & Gynecol, Brooklyn, NY 11203 USA
[3] Johns Hopkins Univ, Sch Publ Hlth, Div Epidemiol, Baltimore, MD USA
[4] Cook Cty Hosp, Dept Obstet & Gynecol, Chicago, IL 60612 USA
[5] Rush Med Coll, Dept Obstet & Gynecol, Chicago, IL 60612 USA
[6] Montefiore Med Ctr, Dept Med, Bronx, NY 10467 USA
[7] Lincoln Med & Mental Hlth Ctr, Dept Med, Bronx, NY USA
[8] NICHHD, Bethesda, MD 20892 USA
[9] NCI, Bethesda, MD 20892 USA
[10] Univ So Calif, Dept Obstet & Gynecol, Los Angeles, CA 90089 USA
[11] Univ Calif San Francisco, Dept Med, San Francisco, CA USA