1. Department of Obstetrics and Gynecology Women's HospitalHelsinki University Hospital and University of Helsinki Helsinki Finland
2. Information Services Department Finnish Institute for Health and Welfare Helsinki Finland
3. Department of Neurobiology, Care Sciences and Society Karolinska Institute Stockholm Sweden
4. Retired from the Register of Congenital Malformations Finnish Institute for Health and Welfare Helsinki Finland
5. Department of Pediatric Cardiology Children's Hospital Helsinki University Hospital and University of Helsinki Helsinki Finland
6. Division of Pediatric 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
8. Department of Clinical Medicine, Biostatistics University of Turku Turku Finland