1. Department of Obstetrics and Gynaecology Lyell McEwin Hospital Adelaide South Australia Australia
2. School of Public Health University of AdelaideAdelaideSouth AustraliaAustralia
3. The Robinson Institute School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
4. Division of Applied Health Sciences University of Aberdeen Aberdeen Maternity Hospital Aberdeen UK
5. Population Health Sciences University of Bristol Bristol UK
6. Maternal and Foetal Medicine Service Women's and Children's Hospital Adelaide South Australia Australia
7. Department of Obstetrics and Gynaecology Monash Medical Centre Monash University Melbourne Victoria Australia