title: Reply.
authors.affiliation: Brigham and Women's Hospital, Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA. Electronic address: kvenkatesh@partners.org.
authors.forename: Kartik K
authors.initials: KK
authors.lastname: Venkatesh
authors.affiliation: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA.
authors.forename: Anjali J
authors.initials: AJ
authors.lastname: Kaimal