1. Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, British Columbia;
2. Children’s and Women’s Hospital and Health Centre of British Columbia, Vancouver, British Columbia;
3. Maternal, Child and Youth Health, Surveillance and Epidemiology Division, Centre for Chronic Disease Prevention, Public Health Agency of Canada, Ottawa, Ontario;
4. The Hospital for Sick Children, Toronto, Ontario;
5. Division of Neonatology, University of Toronto, Toronto, Ontario;
6. School of Population and Public Health, University of British Columbia, Vancouver, British Columbia;
7. The BC Children’s Hospital Research Institute, Vancouver, British Columbia