1. Department of Obstetrics and Gynecology, University of Zaragoza Faculty of Medicine, Hospital Clinico Lozano-Blesa, Zaragoza, Spain;
2. Red de Investigacion de Ginecologia, Obstetricia y Reproduccion, Instituto Aragones de Ciencias de la Salud (IACS), Zaragoza, Spain;
3. University of Conneticut/Hartford Hospital Evidence-based Practice Center, Hartford, CT, USA;
4. School of Medicine, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru