1. Division of Maternal–Fetal Medicine Department of Obstetrics and Gynaecology Sunnybrook Health Sciences Centre University of Toronto Toronto ON Canada
2. Institute of Medical Sciences University of Toronto Toronto ON Canada
3. Department of Obstetrics and Gynecology McMaster University Hamilton ON Canada
4. Division of Maternal–Fetal Medicine Departments of Obstetrics and Gynaecology Mount Sinai Hospital University of Toronto Toronto ON Canada
5. Department of Medicine and Institute for Health Policy, Management and Evaluation Institute for Clinical Evaluative Sciences Sunnybrook Research Institute Toronto ON Canada
6. Department of Medicine Sunnybrook Health Sciences Centre University of Toronto Toronto ON Canada