1. Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden
2. Department of Obstetrics and Gynecology, Sundsvall County Hospital, Sundsvall, Sweden
3. Department of Clinical Sciences, Obstetrics and Gynecology, Sundsvalls Research Unit, Umeå University, Umeå, Sweden
4. Departments of Epidemiology, Biostatistics & Occupational Health and of Pediatrics, McGill University Faculty of Medicine, Montreal, Quebec, Canada
5. Department of Obstetrics and Gynaecology, National University Hospital, National University of Singapore, Singapore