[1] Leiden Univ, Med Ctr, Leiden, Netherlands
[2] Univ Louvain, Louvain, Belgium
[3] Univ Strasbourg CMCO HUS, Strasbourg, France
[4] Univ Birmingham, Fetal Med Ctr, Birmingham Womens Fdn Trust, Birmingham, W Midlands, England
[5] Childrens Hosp V Buzzi, Milan, Italy