1. Department of Obstetrics and Gynaecology, Hospital Clínico San Cecilio, Facultad de Medicina, Universidad de Granada, Granada, Spain;
2. Instituto de Biomedicina, Facultad de Medicina, Universidad Cató lica de Guayaquil, Ecuador;
3. Department of Obstetrics and Gynaecology, University of Zaragoza Hospital Clínico, Zaragoza, Spain