1. Clinic of Obstetrics and Gynaecology, St. Franziskus-Hospital, Münster, Germany,
2. Clinic of Obstetrics and Gynaecology, University of Münster, Germany,
3. Clinic of Obstetrics and Gynaecology, University of Udine, Italy,
4. Department of Clinical and Biological Sciences, University of Udine, Italy, and
5. Clinic of Surgical Semeiotics, University of Udine, Italy