1. Obstetrics and Gynecology, University of Navarra Clinic, Pamplona, Spain
2. Obstetrics and Gynecology, University Hospital Complex Badajoz, Spain
3. Obstetrics and Gynecology, Araba University Hospital Txagorritxu Campus, Vitoria-Gasteiz, Spain
4. Obstetrics and Gynecology, Virgen de la Arrixaca University Hospital, El Palmar, Spain
5. Obstetrics and Gynecology, Università degli Studi di Cagliari, Italy
6. Obstetrics and Gynecology, Institut Universitari Dexeus, Barcelona, Spain