[1] Univ Autonoma Barcelona, Hosp Univ Vall dHebron, Dept Obstet, Maternal Fetal Med Unit, Passeig Vall dHebron 119-129, Barcelona 08035, Spain
[2] Univ Autonoma Barcelona, Hosp Univ Germans Trias & Pujol, Dept Obstet, Maternal Fetal Med Unit, Badalona, Spain
[3] Univ Rovira & Virgili, Hosp Univ Tarragona Joan XXIII, Dept Obstet, Maternal Fetal Med Unit, Tarragona, Spain
[4] Univ Barcelona, Hosp Univ Mutua Terrassa, Dept Obstet, Maternal Fetal Med Unit, Terrassa, Spain
[5] Univ Int Catalunya, Consorci Sanit Terrassa, Dept Obstet, Maternal Fetal Med Unit, Terrassa, Spain
[6] Univ Girona, Hosp Univ Girona Doctor Josep Trueta, Dept Obstet, Maternal Fetal Med Unit, Girona, Spain