1. IIS Aragon, Hospital Universitario Miguel Servet, Zaragoza University, Madrid, Spain
2. Instituto de Salud de la Mujer, Hospital Clinico San Carlos, IdISSC, Complutense University, Madrid, Spain
3. Department of Obstetrics and Gynecology, Hospital Universitario de Guadalajara, Guadalajara, Spain
4. Universidad de Alcalá de Henares, Madrid, Spain
5. Department of Obstetrics and Gynecology, Quiron Salud Hospital Universitari General de Catalunya, Barcelona, Spain
6. Department of Obstetrics and Gynecology, Hospital de Cruces, University of the Basque Country, Bilbao, Spain
7. Salud Sexual y Reproductiva, Unidad de Gestión Clínica Cayetano Roldan, San Fernando, Cadiz, Spain
8. Department of Obstetrics and Gynecology, Hospital Central de Asturias, Faculty of Medicine, Oviedo University, Spain
9. Department of Obstetrics and Gynecology, Faculty of Medicine, Granada University, Spain