1. Department of Obstetrics and Gynaecology School of Health and Medical Sciences Örebro University Örebro Sweden
2. Clinical Epidemiology and Biostatistics Örebro University Hospital School of Medical Health and Sciences Örebro University Örebro Sweden
3. Clinical Epidemiology Unit Karolinska Institutet Stockholm Sweden
4. Department of Women's and Children's Health Uppsala University Uppsala Sweden
5. Department of Internal Medicine School of Health and Medical Sciences Örebro University Örebro Sweden