| Problem: Breastfeeding may decrease the development of breast cancer in mothers, and recent studies suggest this protection may be particularly greatest among premenopausal women. The purpose of this literature review is to critically examine existing studies to determine if there is an association between breastfeeding and the risk of developing premenopausal breast cancer. Methods: A computerized literature review was conducted using MEDLINERTM from 1926 to 2010 to identify original articles in English relating to breastfeeding and breast cancer. Results: While results from all studies remain inconsistent, most studies indicate there is a protective effect of breastfeeding against breast cancer among premenopausal women and this effect may be more pronounced with ever having breastfed, increasing breastfeeding duration, increasing number of children breastfed, initiating breastfeeding at a young age, and among women with family histories of breast cancer who have ever breastfed. Conclusion: Overall, data from a few review articles, several large cohort studies, as well as numerous case-control studies suggest that breastfeeding confers protection against premenopausal breast cancer development. Understanding the role breastfeeding plays on breast cancer risk has important public health implications. Consideration should be taken for advocating breastfeeding when developing breast cancer prevention programs, and clinicians should take into account breastfeeding history when outlining risk management strategies. Future research is required to understand the biological mechanism behind this association as well as determine if there is differential protection against various subtypes of breast cancer. |
