[1] Ist Super Sanita, Dept Therapeut Res & Med Evaluat, I-00161 Rome, Italy
[2] Catholic Univ, Dept Infect Dis, Rome, Italy
[3] INMI Lazzaro Spallanzani, Rome, Italy
[4] Univ Turin, Dept Obstet & Gynecol, Turin, Italy
[5] AO OIRM S Anna, Turin, Italy
[6] Univ Milan, Dept Obstet & Gynecol, Milan, Italy
[7] L Sacco Hosp Vialba, Milan, Italy
[8] Univ Modena & Reggio Emilia, Dept Med Special, Infect Dis Clin, Modena, Italy
[9] Univ Padua, Dept Pediat, Padua, Italy
[10] Univ Bari, Dept Obstet & Gynecol, Bari, Italy
[11] Policlin Hosp, Bari, Italy
[12] Univ Naples Federico 2, Dept Obstet & Gynaecol, Naples, Italy
[13] Azienda Osped Piacenza, Infect Dis Unit, Piacenza, Italy
[14] S Paolo Hosp, Dept Obstet & Gynecol, Milan, Italy