[1] Univ Oulu, Univ Hosp Oulu, Dept Obstet & Gynecol, Med Res Ctr Oulu, Oulu, Finland
[2] Univ Oulu, Univ Hosp Oulu, PEDEGO Res Unit, Res Unit Pediat Dermatol Clin Genet Obstet & Gyne, Oulu, Finland
[3] Imperial Coll London, Inst Reprod & Dev Biol, London, England
[4] Univ Oulu, Fac Med, Ctr Life Course Hlth Res, Oulu, Finland
[5] Oulu Univ Hosp, Unit Gen Practice, Oulu, Finland
[6] Univ Oulu, Oulu Univ Hosp, Dept Clin Chem, NordLab Oulu, Oulu, Finland
[7] Natl Inst Hlth & Welf, Dept Children Young People & Families, Oulu, Finland
[8] Imperial Coll London, MRC Hlth Protect Agcy HPA Ctr Environm & Hlth, Sch Publ Hlth, Dept Epidemiol & Biostat, London, England
[9] Univ Helsinki, Dept Obstet & Gynecol, Helsinki, Finland
[10] Helsinki Univ Hosp, Helsinki, Finland