1. Department of Obstetrics; Leiden University Medical Centre Leiden; Leiden the Netherlands
2. Department of Obstetrics and Gynaecology; Academic Medical Centre; Amsterdam the Netherlands
3. Julius Center for Health Sciences and Primary Care; Univerity Medical Center Utrecht; Utrecht the Netherlands
4. Department of Obstetrics and Gynaecology; Ikazia Hospital; Rotterdam the Netherlands
5. Department of Obstetrics and Gynaecology; Flevo Hospital; Almere the Netherlands
6. Department of Obstetrics and Gynaecology; Meander Medical Centre; Amersfoort the Netherlands
7. Department of Obstetrics and Gynaecology; Rijnstate Hospital; Arnhem the Netherlands
8. Department of Obstetrics and Gynaecology; Medical Spectrum Twente; Enschede the Netherlands
9. Wilhelmina Children's Hospital Birth Centre; University Medical Centre Utrecht; Utrecht the Netherlands
10. The Robinson Research Institute; School of Paediatrics and Reproductive Health; University of Adelaide; Adelaide SA Australia
11. South Australian Health and Medical Research Institute; Adelaide SA Australia