1. Department of Obstetrics & Gynecology Baylor College of Medicine Houston Texas USA
2. Department of Obstetrics & Gynecology Beth Israel Deaconess Medical Center Boston Massachusetts USA
3. Department of Obstetrics, Gynecology, and Reproductive Biology Harvard Medical School Boston Massachusetts USA
4. Maternal and Child Health Research Center, Department of Obstetrics & Gynecology, Perelman School of Medicine University of Pennsylvania Philadelphia Pennsylvania USA
5. Department of Obstetrics and Gynecology Women's Health Hospital, Faculty of Medicine, Assiut University Assiut Egypt