The authors declare that there is no conflict of interest.
Main Research Article
Induced abortion and breast cancer among parous women: a Danish cohort study
Article first published online: 13 APR 2013
© 2013 The Authors Acta Obstetricia et Gynecologica Scandinavica © 2013 Nordic Federation of Societies of Obstetrics and Gynecology
Acta Obstetricia et Gynecologica Scandinavica
Volume 92, Issue 6, pages 700–705, June 2013
How to Cite
Induced abortion and breast cancer among parous women: a Danish cohort study.. Acta Obstet Gynecol Scand 2013; 00:000–000., , , .
- Issue published online: 16 MAY 2013
- Article first published online: 13 APR 2013
- Accepted manuscript online: 12 FEB 2013 09:39AM EST
- Manuscript Accepted: 5 FEB 2013
- Manuscript Received: 3 SEP 2012
- Department of Gynecology and Obstetrics, Vendsyssel Hospital
- Breast neoplasms;
- induced abortion;
- alcohol drinking;
We investigated whether induced abortion is associated with breast cancer when lifestyle confounders, including smoking and alcohol consumption, are adjusted for. Design. Prospective cohort study.
Danish women from the Diet, Cancer and Health study.
A total of 25 576 women.
We obtained exposure data from baseline questionnaires filled in by the women between 1993 and 1997. Information on breast cancer and emigration was retrieved from Danish national registries. The study power was approximately 85% when applying a minimum detection hazard ratio of 1.2.
Main outcome measures
Long-term effects of induced abortion on the risk of breast cancer among women above 50 years of age.
During a follow up of approximately 12 years, 1215 women were diagnosed with breast cancer. When comparing parous women who had an abortion with parous women who never had an abortion, there was no association between breast cancer risk and induced abortion (ever vs. never), with a hazard ratio 0.95 (95% confidence interval 0.83–1.09), regardless of whether the abortion occurred before the first birth (hazard ratio 0.86; 95% confidence interval 0.65–1.14), or after the first birth (hazard ratio 0.97; 95% confidence interval 0.84–1.13).
Our study did not show evidence of an association between induced abortion and breast cancer risk.