1. Department of Obstetrics and Gynaecology Women's Hospital Helsinki University Hospital and University of Helsinki Helsinki Finland
2. Information Services Department National Institute for Health and Welfare Helsinki Finland
3. Division of Family Medicine Department of Neurobiology, Care Sciences and Society Karolinska Institute Stockholm Sweden
4. Register of Congenital Malformations National Institute for Health and Welfare Helsinki Finland
5. Department of Paediatric Cardiology Children's Hospital Helsinki University Hospital and University of Helsinki Helsinki Finland
6. Division of Paediatric Surgery Children's Hospital Helsinki University Hospital and University of Helsinki Helsinki Finland
7. Children's Hospital Helsinki University Hospital and University of Helsinki Helsinki Finland