1. Department of Obstetrics and Gynaecology; Sacro Cuore Hospital; Negrar,
2. Department of Obstetrics and Gynaecology, Umberto I Hospital; University of Turin; Turin,
3. Department of Obstetrics and Gynaecology; University Federico II of Naples; Naples and
4. Complex Operative Unit of Obstetrics and Gynaecology; S. Iacopo Hospital; Pistoia Italy