1. Department of Obstetrics and Gynaecology, University Hospital Complex Insular Materno-Infantil of Gran Canaria, Canary Health Service, Avda Marítima del Sur S/N, CP 35016 Las Palmas de Gran Canaria, Spain
2. Labour Ward Unit., General Hospital of Fuerteventura Virgen de la Peña-Canary Health Service, Carretera del Aeropuerto, Km 1, CP 35600 Puerto del Rosario, Spain
3. Department of Nursing, University of Las Palmas de Gran Canaria, Edificio Ciencias de la Salud, C/Blas Cabrera Felipe S/N, CP 35016 Las Palmas de Gran Canaria, Spain
4. Research Support Unit of University Hospital Complex Insular Materno-Infantil of Gran Canaria, Canary Health Service, Avda Marítima del Sur S/N, CP 35016 Las Palmas de Gran Canaria, Spain
5. Multiprofessional Teaching Unit of Obstetrics and Gynaecology of the University Hospital Complex Insular Materno-Infantil of Gran Canaria, Canary Health Service, Avda Marítima del Sur S/N, CP 35016 Las Palmas de Gran Canaria, Spain