1. Gynecology and Obstetrics Department I.R.C.C.S. San Raffaele Hospital, University Vita e Salute Milan Italy
2. Obstetric Unit, Department of Medical and Surgical Sciences University of Bologna and IRCCS Azienda Ospedaliero‐Universitaria Sant'Orsola‐Malpighi Bologna Italy
3. Department of Obstetrics and Gynecology Sant'Anna University Hospital Cona Ferrara Italy