Affiliation: | a Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, New York University School of Medicine, New York, NY b Human Genetics Program, New York University School of Medicine, New York, NY c Statistics and Mapping Laboratory, New York University, New York, NY d Department of Obstetrics and Gynecology, Lenox Hill Hospital, New York, NY e Genzyme Genetics, Philadelphia, PA |