[1] Norwegian Inst Publ Hlth, Div Mental & Phys Hlth, Oslo, Norway
[2] Univ Oxford, Oxford Dept Populat Hlth, Natl Perinatal Epidemiol Unit, Oxford, England
[3] Univ Med Ctr, Wilhelmina Childrens Hosp, Div Women & Baby, Dept Obstet, Utrecht, Netherlands
[4] Italian Natl Inst Hlth, Natl Ctr Dis Prevent & Hlth Promot, Ist Super Sanita, Rome, Italy
[5] Natl Inst Hlth & Med Res INSERM, Paris, France
[6] Helsinki Univ Hosp, Dept Obstet & Gynecol, Helsinki, Finland
[7] Univ Helsinki, Helsinki, Finland
[8] Copenhagen Univ Hosp Holbaek, Dept Obstet & Gynecol, Holbaek, Denmark
[9] Copenhagen Univ Hosp Nordsjaelland Hillerod, Dept Obstet & Gynecol, Hillerod, Denmark
[10] Landspitali Univ Hosp, Dept Obstet & Gynecol, Reykjavik, Iceland
[11] Sahlgrens Univ Hosp, Dept Obstet & Gynecol, Reg Vastra Gotaland, Gothenburg, Sweden
[12] Univ Libre Bruxelles ULB, Hop Univ Bruxelles HUB, Dept Obstet & Gynecol, CUB Hop Erasme, Brussels, Belgium