1. Department of Obstetrics, Gynaecology and Fertility, Faculty of Medicine, University of Amsterdam (AMC-UvA), Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
2. Department of Obstetrics and Gynaecology, Faculty of Medicine, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam, The Netherlands
3. Department of Public and Occupational Health, EMGO+ Institute for Health and Care Research, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands