1. Centre for Fertility and Health Norwegian Institute of Public Health Oslo Norway
2. MRC Integrative Epidemiology Unit at the University of Bristol Bristol UK
3. Department of Non‐communicable Disease Epidemiology London School of Hygiene and Tropical Medicine London UK
4. Department of Global Public Health and Primary Care University of Bergen Bergen Norway
5. Division of Clinical Epidemiology Department of Medicine, Solna Karolinska Institutet Stockholm Sweden
6. Department of Women's Health Karolinska University Hospital, Solna Stockholm Sweden
7. Department of Health Registry Research and Development Norwegian Institute of Public Health Oslo Norway
8. Department of Obstetrics and Gynecology Haukeland University Hospital Bergen Norway
9. Department of Clinical Science University of Bergen Bergen Norway
10. Department of Public Health University of Copenhagen Copenhagen Denmark