[1] Arctic Univ Norway, Univ Tromso, Dept Clin Med, Fac Hlth Sci,Womens Hlth & Perinatol Res Grp, Tromso, Norway
[2] Univ Hosp Northern Norway, Dept Obstet & Gynaecol, Tromso, Norway
[3] Arctic Univ Norway, Univ Tromso, Univ Lib, Sci & Hlth Lib, Tromso, Norway
[4] Arctic Univ Norway, Univ Tromso, Fac Hlth Sci, Dept Community Med, Tromso, Norway
[5] Polytech Univ Marche, Dept Clin Sci & Stomatol, Ancona, Italy
[6] Univ Ferrara, Dept Med Sci, Ferrara, Italy
[7] Karolinska Inst, Dept Clin Sci Intervent & Technol, Stockholm, Sweden
[8] Karolinska Univ Hosp, Ctr Fetal Med, Stockholm, Sweden