1. Department of Obstetrics and Gynaecology; GROW School for Oncology and Developmental Biology; Maastricht University Medical Centre+; Maastricht the Netherlands
2. Department of Epidemiology; Caphri School for Public Health and Primary Care; Maastricht University; Maastricht the Netherlands
3. Department of Obstetrics and Gynaecology; Orbis Medical Centre; Sittard the Netherlands
4. Department of Obstetrics and Gynaecology; Hospital Rijnstate; Arnhem the Netherlands
5. Department of Obstetrics and Gynaecology; Elkerliek Hospital; Helmond the Netherlands
6. Department of Obstetrics and Gynaecology; St. Jans Hospital; Weert the Netherlands
7. Department of Obstetrics and Gynaecology; Groningen University Medical Centre; Groningen the Netherlands
8. Department of Obstetrics and Gynaecology; Röpcke-Zweers Hospital; Hardenberg the Netherlands
9. Department of Obstetrics and Gynaecology; Flevo Hospital; Almere the Netherlands
10. Department of Obstetrics and Gynaecology; Catharina Hospital; Eindhoven the Netherlands
11. Department of Obstetrics and Gynaecology; University Medical Centre Utrecht; Utrecht the Netherlands
12. Department of Obstetrics and Gynaecology; IJsselland Hospital; Capelle aan den IJssel the Netherlands
13. Department of Obstetrics and Gynaecology; Academic Medical Centre; University of Amsterdam; Amsterdam the Netherlands
14. Department of Obstetrics and Gynaecology; Atrium Medical Centre; Heerlen the Netherlands
15. Department of Obstetrics and Gynaecology; ZiekenhuisGroepTwente; Almelo the Netherlands
16. Department of Obstetrics and Gynaecology; Ruwaard van Putten Hospital; Spijkenisse the Netherlands
17. Department of Obstetrics and Gynaecology; Tergooi Hospital; Hilversum the Netherlands
18. Department of Obstetrics and Gynaecology; Radboud University Medical Centre; Nijmegen the Netherlands
19. Scientific Institute for Quality of Healthcare (IQ healthcare); Radboud University Nijmegen Medical Centre; Nijmegen the Netherlands