1 Department of Gynaecology and Obstetrics, University Hospital Tuebingen, Calwerstrasse 7, 72076, Tuebingen, Germany.
2 Department of Gynaecology and Obstetrics, University Hospital Tuebingen, Calwerstrasse 7, 72076, Tuebingen, Germany. christl.reisenauer@med.uni-tuebingen.de.