[1] Katholieke Univ Leuven, Grp Biomed Sci, Dept Dev & Regenerat, Cluster Organ Syst, Leuven, Belgium
[2] Clin Alemana, Dept Obstet & Gynaecol, Santiago, Chile
[3] Univ Hosp KU Leuven, Dept Obstet & Gynaecol, Leuven, Belgium
[4] Univ Hosp KU Leuven, Dept Paediat, Leuven, Belgium
[5] Univ Coll London Hosp, Inst Womans Hlth, London, England
[6] Great Ormond St Hosp Sick Children, London, England