1. Department of Obstetrics and Gynaecology, Faculty of Medicine, Assiut University Women’s Health Center, P.O. Box 30, Assiut, Egypt
2. Department of Obstetrics and Gynaecology, El Galaa Maternity Teaching Hospital, Cairo, Egypt
3. Department of Obstetrics, Gynaecology and Reproductive Sciences, University of California, San Francisco, CA, USA