[1] Univ Milan, Midwifery Sch, Dept Clin Sci & Community Hlth, Via Manfredo Fanti 6, I-20122 Milan, Italy
[2] Fdn IRCCS CaGranda Osped Maggiore Policlin, SITRA Unit, Via Francesco Sforza 35, I-20122 Milan, Italy
[3] St Anna Hosp, Obstet & Gynecol Dept 3, Corso Spezia 60, I-10126 Turin, Italy
[4] Univ Campus Bio Med Roma, Dept Obstet & Gynecol, Via Alvaro Portillo,21, I-00128 Rome, Italy
[5] Biella Univ Turin, Gen Hosp, Obstet & Gynecol Dept, Via Ponderanesi 2, I-13875 Ponderano, Biella, Italy
[6] Madonna delle Grazie Hosp ASM, Dept Maternal & Child Hlth, Contrada Cattedra Ambulante, I-75100 Matera, Italy
[7] Hosp AO Emergency Cannizzaro, Dept Maternal & Child Hlth, Obstet & Gynecol Unit, Via Messina 829, I-95126 Catania, Italy
[8] Osped Fatebenefratelli Hosp, Gemelli Isola Tiberina, Obstet Pathol Unit, Via Ponte Quattro Capi 39, I-00186 Rome, Italy
[9] Fdn IRCCS CaGranda Osped Maggiore Policlin, Obstet Unit, Via Commenda 12, I-20122 Milan, Italy
[10] Assoc Ostetr & Ginecol Italiani, Via Abamonti 1, I-20129 Milan, Italy