1. From the Department of Obstetrics and Gynecology, Brigham and Women’s Hospital (S.E.L.), the Departments of Radiology (O.A.C.), Obstetrics and Gynecology (A.G.E.), and Pathology (S.G.S.), Massachusetts General Hospital, and the Departments of Radiology (O.A.C.), Obstetrics and Gynecology (S.E.L., A.G.E.), and Pathology (S.G.S.), Harvard Medical School — all in Boston.