1. University of Amsterdam; Academic Medical Centre, Obstetrics and Gynaecology; PO Box 22660 Amsterdam Netherlands 1100 DD
2. Academic Medical Center, University of Amsterdam; Obstetrics and Gynecology; Meibergdreef 9 Amsterdam Netherlands 1105 AZ
3. Máxima Medical Center; Obstetrics and Gynecology; Postbox 7777 Veldhoven Netherlands 5500 MB
4. Academic Medical Center, University of Amsterdam; Department of Clinical Epidemiology and Biostatistics; Room J2-209, PO Box 22700 Amsterdam Netherlands 1105 DD
5. Academie Medical Center; Department of Obstetrics & Gynaecology; University of Amsterdam P O Box 22700 Amsterdam Netherlands 1100 DE
6. Academic Medical Center; Center for Reproductive Medicine - H4-205, Department of Obstetrics & Gynaecology; University of Amsterdam Meibergdreef 9 Amsterdam Netherlands 1105 AZ