1. Department of Obstetrics and Gynecology, University of Siena, Siena, Italy; Nuffield Department of Obstetrics and Gynecology, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
2. Department of Obstetrics and Gynecology, University of Siena, Siena, Italy; Nuffield Department of Obstetrics and Gynecology, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom; Chair of Obstetrics and Gynecology, University of Siena, Policlinico “Le Scotte,” Viale Bracci, 53100 Siena, Italy