1. Finnish Cancer RegistryInstitute for Statistical and Epidemiological Cancer Research Helsinki Finland
2. Department of Obstetrics and GynecologyKymenlaakso Central Hospital Kotka Finland
3. Department of Public Health, School of MedicineUniversity of Helsinki Helsinki Finland
4. Information Services DepartmentNational Institute for Health and Welfare Helsinki Finland
5. Department of Neurobiology, Care Science and SocietyKarolinska Institute Stockholm Sweden
6. Department of Obstetrics and GynecologyUniversity of Helsinki, Helsinki University Hospital Helsinki Finland