1. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
2. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, The University of Utah, Salt Lake City
3. Department of Obstetrics and Gynecology, Indiana University School of Medicine, Indianapolis
4. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Perelman School of Medicine, University of Pennsylvania, Philadelphia
5. Department of Obstetrics and Gynecology, The MetroHealth System, Case Western Reserve University, Cleveland, Ohio
6. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of California, Irvine
7. Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Science, Yale University, New Haven, Connecticut
8. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston
9. Department of Obstetrics, Gynecology, and Reproductive Science, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania