1. University of Amsterdam; Department of Obstetrics & Gynaecology, Academic Medical Centre; Amsterdam Netherlands
2. University of Auckland; Obstetrics and Gynaecology; FMHS Park Road Grafton Auckland New Zealand 1003
3. University of Amterdam; Department of Obstetrics & Gynaecology Academic Medical Centre; PO BOX 22660 Amsterdam Netherlands 1100 DD
4. University of Amsterdam; Department of Obstetrics & Gynaecology Academic Medical Centre; 1100 DD Amsterdam PO BOX 22660 Amsterdam Netherlands 1100