1. Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
2. Department Obstetrics and Gynecology, TweeSteden Hospital, Dr. Deelenlaan 5, 5042 AD Tilburg, The Netherlands
3. Department Obstetrics and Gynecology, Academic Medical Center, Amsterdam, The Netherlands
4. Department Obstetrics and Gynecology, Erasmus MC, s-Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands
5. Department Obstetrics and Gynecology, Maxima Medisch Centrum, De Run 4600, 5504 DB Veldhoven, The Netherlands