1. Unit of Reproductive Endocrinology, 1st Department of Obstetrics and Gynaecology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece;
2. Police Medical Centre of Thessaloniki, Thessaloniki, Greece;
3. Department of Clinical Biochemistry and Department of Surgery, Royal Free Hospital Campus, University College Medical School, University College London, London, UK;
4. Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai