1. Research Support Unit of Insular Maternal and Child University Hospital Complex of Gran Canaria, Canary Health Service, Avda Marítima del Sur S/N, 35016 Las Palmas de Gran Canaria-Canary Islands, Spain
2. Department of Nursing, University of Las Palmas de Gran Canaria, Edificio Ciencias de la Salud, C/Blas Cabrera Felipe s/n, 35016 Las Palmas de Gran Canaria-Canary Islands, Spain
3. Department of Obstetrics and Gynaecology, Insular Maternal and Child University Hospital Complex of Gran Canaria, Canary Health Service, Avda Marítima del Sur S/N, 35016 Las Palmas de Gran Canaria-Canary Islands, Spain
4. Department of Community Nursing, Preventive Medicine, Public Health and History of Science, Faculty of Health Sciences, University of Alicante (UA), 03690 Alicante, Spain