[1] Univ Ottawa, Fac Med, Ottawa, ON, Canada
[2] Mem Univ Newfoundland, Fac Med, St John, NF, Canada
[3] Vancouver Gen Hosp, Dept Radiol, Vancouver, BC, Canada
[4] Univ Toronto, Dept Obstet & Gynecol, Toronto, ON, Canada
[5] King Abdulaziz Univ, Dept Obstet & Gynecol, Fac Med, Jeddah, Saudi Arabia