1. Department of Obstetrics and Gynecology, Mansoura Medical School, Mansoura, Egypt;
2. Department of Obstetrics and Gynecology, Medical College of Georgia, Augusta University, Augusta, GA, USA;
3. Department of Obstetrics and Gynecology, University of Texas Medical Branch at Galveston, Galveston, TX, USA;
4. Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, Rockefeller University, New York, NY, USA;
5. Department of Research, American College of Obstetricians and Gynecologists, Washington, DC, USA