1 Unit of Reproductive Endocrinology and Unit of Human Reproduction, First Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, 'Papageorgiou' General Hospital, Ring Road, 54601 Nea Efkarpia, Thessaloniki, Greece.
2 Unit of Reproductive Endocrinology and Unit of Human Reproduction, First Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, 'Papageorgiou' General Hospital, Ring Road, 54601 Nea Efkarpia, Thessaloniki, Greece dgg@auth.gr.