1. Department of Obstetrics and Gynecology, North York General Hospital, Toronto, Ontario, Canada
2. ICES, Toronto, Ontario, Canada
3. Department of Obstetrics and Gynecology, St Michael’s Hospital, Toronto, Ontario, Canada
4. Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
5. Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada