1. Department of Obstetrics and Gynaecology, University Hospital of Ioannina, 451 10 Ioannina, Greece
2. Assisted Conception Unit, Guy’s and St Thomas’ Hospital NHS Foundation Trust, London SE1 9RT, UK
3. Department of Gynaecology, St George’s University Hospitals NHS Foundation Trust, London WC1E 6BT, UK
4. Department of Medical and Surgical Sciences, Institute of Obstetrics and Gynecology, University of Foggia, 71121 Foggia, Italy
5. 2nd Department of Obstetrics and Gynaecology, Hippokration General Hospital, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece