[1] Univ Copenhagen, Dept Obstet & Gynaecol, Hvidovre Hosp, DK-2650 Hvidovre, Denmark
[2] Univ Copenhagen, Clin Res Ctr, Hvidovre Hosp, DK-2650 Hvidovre, Denmark
[3] Aarhus Univ Hosp, Dept Obstet & Gynaecol, Skejby, Denmark
[4] Univ Copenhagen, Rigshosp, Res Unit Womens & Childrens Hlth, Juliane Marie Ctr, DK-2100 Copenhagen, Denmark