1. Department of Obstetrics and Gynecology, Clinica Universidad de Navarra; University of Navarra; Pamplona Spain
2. Department of Obstetrics, Gynecology and Reproduction, Institut Dexeus; University Autonoma of Barcelona; Barcelona Spain
3. Department of Obstetrics and Gynecology, Policlinico Universitario Duilio Casula; University of Cagliari; Monserrato Cagliari Italy