Affiliation: | 1. Department of Obstetrics and Gynecology, VU University Medical Center, Amsterdam, the Netherlands;2. Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, the Netherlands;3. Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, the Netherlands;4. Department of Obstetrics and Gynecology, Leiden University Medical Center, Leiden, the Netherlands |