1. INSERM UMRS 953 Epidemiological Research Unit on Perinatal and Women's and Children's Health Paris France
2. UPMC Paris France
3. Department of Epidemiology National Research Institute of Mother and Child Warsaw Poland
4. Department Child Health TNO Netherlands Organization for Applied Scientific Research Leiden the Netherlands
5. Information Services Division NHS National Services Scotland Edinburgh UK
6. Estonian Institute for Population Studies Tallinn University Tallinn Estonia
7. Department of Public Health and Primary Health Care University of Bergen Bergen Norway
8. Medical Birth Registry of Norway Norwegian Institute of Public Health Bergen Norway
9. Department of Health Information and Research National Obstetric Information Systems (NOIS) Register G'Mangia Malta
10. Department of Information THL National Institute for Health and Welfare Helsinki Finland
11. Nordic School of Public Health Gothenburg Sweden