[1] Med Univ Vienna, Dept Obstet & Fetomaternal Med, Wahringer Gurtel 18-20, A-1090 Vienna, Austria
[2] Middle East Tech Univ Ankara, Fac Arts & Sci, Dept Stat, Ankara, Turkey
[3] Ankara Univ, Dept Obstet & Gynecol, Ankara, Turkey
[4] St Georges Univ London, St Georges Hosp, Fetal Med Unit, London, England
[5] St Georges Univ London, Mol & Clin Sci Res Inst, Vasc Biol Res Ctr, London, England