1. Department of Obstetrics and Gynecology; Clínica Universidad de Navarra, School of Medicine, University of Navarra; Pamplona Spain
2. Department of Obstetrics and Gynecology; University Hospital Virgen de las Nieves; Granada Spain
3. Centro de Diagnóstico TCBA; Buenos Aires Argentina
4. Department of Obstetrics and Gynecology; Canaty Islands University Hospital; Tenerife Spain