1. Department of Obstetrics and Gynecology, Clinica Universidad de Navarra, 31008 Pamplona, Spain
2. Department of Obstetrics and Gynecology, Hospital Universitario de Salamanca, 37007 Salamanca, Spain
3. Department Obstetrics and Gynecology, Centro Hospitalar e Universitário de São João, 4200-319 Porto, Portugal
4. Department of Obstetrics and Gynecology, Hospital Universitario Infanta Sofia, 28702 Madrid, Spain
5. Department of Obstetrics and Gynecology, Hospital Universitario Virgen de la Arrixaca, 30120 Murcia, Spain
6. Department of Obstetrics and Gynecology, Hospital Universitario Virgen de Valme, 41701 Sevilla, Spain
7. Department of Obstetrics and Gynecology, Hospital Universitario Materno-Infantil, 06010 Badajoz, Spain
8. Department of Obstetrics and Gynecology, Hospital General Universitario de Castellón, 12004 Castellón, Spain
9. Department of Obstetrics, Gynecology, and Reproduction, Hospital Universitari Dexeus, 08028 Barcelona, Spain
10. Department of Obstetrics and Gynecology, Hospital Universitario San Carlos, 28040 Madrid, Spain
11. Centro Integrato di Procreazione Medicalmente Assistita (PMA) e Diagnostica Ostetrico-Ginecologica, Azienda Ospedaliero Universitaria-Policlinico Duilio Casula, Monserrato, 09042 Cagliari, Italy
12. Dipartimento di Scienze Chirurgiche, University of Cagliari, 09124 Cagliari, Italy