1 Department of Gynecology and Obstetrics, Justus Liebig University, University of Giessen, Feulgenstr. 10‑12, 35392, Giessen, Germany.
2 Department of Gynecology, UKE Hamburg, Hamburg, Germany.
3 Gynecological Hospital, Frankfurt, Germany.
4 Department of Gynecology and Obstetrics, Justus Liebig University, University of Giessen, Feulgenstr. 10‑12, 35392, Giessen, Germany. lutz.konrad@gyn.med.uni-giessen.de.