1. Public Health and Epidemiology Group, Department of Health Science and Technology Aalborg University Aalborg Denmark
2. Department of Midwifery University College of Northern Denmark Aalborg Denmark
3. Research Center for Health and Applied Technology University College of Northern Denmark Aalborg Denmark
4. Department of Obstetrics and Gynecology Aalborg University Hospital Aalborg Denmark
5. Department of Public Health University of Southern Denmark Odense Denmark