[1] Univ Milan, Unit Obstet & Gynecol, Dept Clin Sci, I-20151 Milan, Italy
[2] Univ Milan, Ctr Fetal Res Giorgio Pardi, I-20151 Milan, Italy
[3] Univ Milan, Inst Obstet & Gynecol, Fdn IRCCS Policlin Mangiagalli & Regina Elena, I-20151 Milan, Italy
[4] Univ Milan, Unit Med Genet, Dept Med Surg & Dent, I-20151 Milan, Italy
[5] Univ Milan, GA Maccacaro Inst Med Stat & Biometry, I-20151 Milan, Italy
[6] Univ Turin, Dept Obstet & Gynecol, I-10124 Turin, Italy
[7] Univ Modena & Reggio Emilia, Mother Infant Dept, Modena, Italy