It has been suggested that taking oral contraceptives (OCs) may increase breast cancer incidence. However, data in this regard are inconsistent. We performed this meta-analysis to estimate the association between OC use and breast cancer risk.
Methods
Prospective cohort studies on OC use and breast cancer risk were identified by searching databases from the period 1960 to 2012. Results from individual studies were synthetically combined using STATA 11 software.
Results
A total of 13 prospective cohort studies were included in our meta-analysis, involving 11,722 cases and 859,894 participants. The combined relative risk (RR) of breast cancer for evercompared with never-OC users was 1.08 (95% confidence interval [CI]: 0.99-1.17). Dose-response analysis based on five eligible studies showed that every ten-years' increment of OC use was associated with a significant 14% (95% CI: 1.05-1.23) rise in breast cancer risk. Little evidence of publication bias was found.
Conclusions
This meta-analysis provides evidence of a non-significant increase in breast cancer risk associated with ever OC use, but the risk for long-term OC users is significantly greater. However, the latter finding is based on only a limited number of studies.
oral contraceptive breast cancer risk meta-analysis prospective cohort, long-term oral contraceptive use breast cancer incidence, OC ever use never use breast cancer relative risk, dose response oral contraceptive duration breast cancer, hormonal contraceptive breast cancer risk systematic review, ten year oral contraceptive use breast cancer risk increase, combined oral contraceptive pill breast cancer prospective study, Zhu meta-analysis oral contraceptives breast cancer, contraceptive pill safety breast cancer epidemiology, oral contraceptive breast cancer SORT evidence review
PMID 23061743 23061743 DOI 10.3109/13625187.2012.715357 10.3109/13625187.2012.715357
Cite this article
Zhu, H., Lei, X., Feng, J., & Wang, Y. (2012). Oral contraceptive use and risk of breast cancer: a meta-analysis of prospective cohort studies. The European journal of contraception & reproductive health care : the official journal of the European Society of Contraception, 17(6), 402-414. https://doi.org/10.3109/13625187.2012.715357
Zhu H, Lei X, Feng J, Wang Y. Oral contraceptive use and risk of breast cancer: a meta-analysis of prospective cohort studies. Eur J Contracept Reprod Health Care. 2012;17(6):402-414. doi:10.3109/13625187.2012.715357
Zhu, H., et al. "Oral contraceptive use and risk of breast cancer: a meta-analysis of prospective cohort studies." The European journal of contraception & reproductive health care : the official journal of the European Society of Contraception, vol. 17, no. 6, 2012, pp. 402-414.
Keywords
Contraceptives, Oral
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