1. Campbell River and District General Hospital; 375 - 2nd Avenue Campbell River British Columbia Canada V9W 3V1
2. University of Exeter Medical School and Peninsula College of Medicine and Dentistry; Barrack Road Exeter UK EX2 5DW
3. South Devon Healthcare Trust; Department of Obstetrics and Gynaecology; Maternity Unit, Torbay Hospital Torquay Devon UK TQ2 7AA
4. The University of Liverpool; Cochrane Pregnancy and Childbirth Group, Department of Women's and Children's Health; First Floor, Liverpool Women's NHS Foundation Trust Crown Street Liverpool UK L8 7SS