title: Reply.
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA.
authors.forename: Adeeb
authors.initials: A
authors.lastname: Khalifeh
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Thomas Jefferson University, 833 Chestnut Street, First Floor, Philadelphia, PA 19107. Electronic address: vincenzo.berghella@jefferson.edu.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Berghella