[1] Univ Toronto, Mt Sinai Hosp, Dept Obstet & Gynaecol, Div Maternal & Fetal Med, Toronto, ON, Canada
[2] Univ Toronto, Mt Sinai Hosp, Dept Med, Pregnancy & Heart Dis Program,Div Cardiol, Toronto, ON, Canada
[3] Univ Toronto, Mt Sinai Hosp, Dept Med, Obstet Med Program,Div Cardiol, Toronto, ON, Canada