1. Department of Clinical Sciences Lund Lund University Lund Sweden
2. Department of Obstetrics and Gynaecology Helsingborg Hospital Helsingborg Sweden
3. Department of Obstetrics and Gynaecology Region Västra Götaland Sahlgrenska University Hospital Gothenburg Sweden
4. Centre of Perinatal Medicine and Health Institute of Clinical Sciences Sahlgrenska Academy Gothenburg Sweden
5. Department of Obstetrics and Gynaecology Ystad lasarett Ystad Sweden
6. Department of Obstetrics and Gynaecology Skåne University Hospital Skåne Sweden
7. Department of Obstetrics and Gynaecology Westmead Hospital Sydney NSW Australia
8. The University of Sydney Sydney NSW Australia
9. Department of Statistics Lund University Lund Sweden
10. Department of Obstetrics and Gynaecology Gold Coast University Hospital Gold Coast Qld Australia
11. Department of Obstetrics and Gynaecology Söder Hospital Stockholm Sweden
12. Institute of Karolinska Stockholm Sweden
13. Department of Clinical Sciences Malmö Lund University Lund Sweden