[1] Copenhagen Univ Hosp, Rigshosp, Dept Obstet, Blegdamsvej 9, DK-2100 Copenhagen, Denmark
[2] Copenhagen Univ Hosp, Rigshosp, Juliane Marie Ctr, Res Unit Womens & Childrens Hlth, Blegdamsvej 9, DK-2100 Copenhagen, Denmark
[3] Univ Copenhagen, Fac Hlth & Med Sci, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
[4] Copenhagen Univ Hosp, Rigshosp, Ctr Pregnancy & Heart Dis, Blegdamsvej 9, Copenhagen, Denmark
[5] North Zealand Hosp, Dept Gynecol & Obstet, Dyrehavevej 29, DK-3400 Hillerod, Denmark
[6] Univ Copenhagen, Dept Publ Hlth, Sect Biostat, Oster Farimagsgade 5,2nd Floor,Postbox 2099, DK-1014 Copenhagen, Denmark
[7] Copenhagen Univ Hosp, Rigshosp, Univ Hosp Ctr Hlth Res UCSF, Sect 9701,Ryesgade 27, DK-2100 Copenhagen, Denmark
[8] Univ Copenhagen, Dept Publ Hlth, Oster Farimagsgade 5, DK-1014 Copenhagen, Denmark
[9] Copenhagen Univ Hosp, Rigshosp, Dept Obstet, Ctr Fetal Med & Pregnancy, Blegdamsvej 9, DK-2100 Copenhagen O, Denmark
[10] Univ Copenhagen, Fac Hlth Sci, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
[11] Univ Copenhagen, Fac Hlth & Med Sci, Inst Clin Med, Blegdamsvej 3, Copenhagen, Denmark