1. Department of Obstetrics and Gynaecology; University of Helsinki and Helsinki University Hospital; Helsinki Finland
2. Information Services Department; THL National Institute for Health and Welfare, Helsinki, Finland
3. Karolinska Institutet, Department of Neurobiology; Care Sciences and Society, Division of Family Medicine; Stockholm Sweden
4. Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research; Helsinki Finland
5. Faculty of Social Sciences; University of Tampere; Finland