1. Maternal Health Care Unit, Faculty of Medicine and Health Örebro University Örebro Sweden
2. University Health Care Research Center Faculty of Medicine and Health, Örebro University Örebro Sweden
3. Department of Women's and Children's Health Akademiska Sjukhuset Uppsala Sweden
4. Clinical Epidemiology and Biostatistics, School of Medical Sciences Örebro University Örebro Sweden
5. Department of Obstetrics and Gynecology, Faculty of Medicine and Health Örebro University Örebro Sweden