1. Second Department of Obstetrics and Gynecology, Aretaeion Hospital, University of Athens, and the Department of Hygiene and Epidemiology, Medical School, University of Athens, Athens, Greece; Second Department of Obstetrics and Gynecology, 124B Vasilisis Sofias Ave, 115 26 Athens, Greece;
2. Second Department of Obstetrics and Gynecology, Aretaeion Hospital, University of Athens, and the Department of Hygiene and Epidemiology, Medical School, University of Athens, Athens, Greece