1. Department of Obstetrics and Gynecology, Johanna-Etienne-Hospital, 41462 Neuss, Germany
2. Teaching Hospital of Heinrich Heine-University Duesseldorf, 40225 Düsseldorf, Germany
3. Clinic of Gynecology, Obstetrics and Gynecological Oncology, University Hospital for Gynecology, Pius Hospital Oldenburg, Medical Campus University of Oldenburg, Germany