1. Department of Obstetrics and Gynaecology, Katholieke Universiteit Leuven, Leuven, Belgium; UZ Gasthuisberg, Department of Obstetrics and Gynaecology, Herestraat 49, B-3000 Leuven, Belgium
2. Department of Obstetrics and Gynaecology, Katholieke Universiteit Leuven, Leuven, Belgium