1. Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, the Netherlands
2. Department of Obstetrics and Gynecology, Isala, Zwolle, the Netherlands
3. Department of Obstetrics and Gynecology, Zuyderland Medical Center, Heerlen, the Netherlands
4. Department of Obstetrics and Gynecology, Máxima Medical Center, Veldhoven, the Netherlands
5. Department of Obstetrics and Gynecology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
6. Department of Obstetrics and Gynecology, Amphia Hospital, Breda, the Netherlands
7. Department of Obstetrics and Gynecology, St Antonius Hospital, Nieuwegein, the Netherlands
8. Department for Health Evidence, Radboud University Medical Center, Nijmegen, the Netherlands
9. for the SAM Study Group