1. Medical Research Group of Egypt, Cairo, Egypt;
2. Kasralainy, Faculty of medicine, Cairo University, Cairo, Egypt;
3. Faculty of medicine, Fayoum University, Fayoum, Egypt;
4. Department of Obstetrics and Gynecology, Faculty of Medicine, Assiut University, Egypt;
5. Department of Obstetrics and Gynecology, Mayo Clinic, Rochester, MN, USA