Maternal Cancer and Illness

The studies below explore the impact that breastfeeding can have on maternal cancer and illness.

Breastfeeding reduces mothers’ cardiovascular disease risk

A meta-analysis of international studies comprised of the health records of nearly 1.2 million women found that women who breastfed at some time in their lives were less likely to develop heart disease or stroke and had a lower risk of dying from cardiovascular disease compared to women who did not breastfeed. Over an average follow-up period of 10 years, women who breastfed at some time in their life were 14% less likely to develop coronary heart disease; 12% less likely to suffer strokes; and 17% less likely to die from cardiovascular disease. There were no notable differences in cardiovascular disease risk among women of different ages or according to the number of pregnancies.

American Heart Association. “Breastfeeding reduces mothers’ cardiovascular disease risk.” ScienceDaily. ScienceDaily, 11 January 2022. www.sciencedaily.com/releases/2022/01/220111091356.htm

Breastfeeding and cardiovascular disease hospitalization and mortality in parous women: evidence from a large Australian cohort study

This study examined the longitudinal association between breastfeeding and maternal cardiovascular disease (CVD) hospitalization and mortality in a large Australian cohort (100,864 parous women aged ≥45). Analysis was restricted to women without self‐reported medically diagnosed CVD at baseline or without past CVD hospitalization 6 years before study entry. Researchers found that ever breastfeeding was associated with lower risk of CVD hospitalization and mortality compared with never breastfeeding, and breastfeeding ≤12 months/child was significantly associated with lower risk of CVD hospitalization.

Nguyen, B, Gale, J, Nassar, N, et al (2019). Breastfeeding and cardiovascular disease hospitalization and mortality in parous women: evidence from a large Australian cohort study. Journal of the American Heart Association, doi.org/10.1161/JAHA.118.011056

Breastfeeding factors and risk of epithelial ovarian cancer

This US study examined the association between breastfeeding factors and epithelial ovarian cancer (EOC). It found that compared to never breastfeeding, breastfeeding any offspring was associated with a 30% reduction in EOC risk. That association lasted more than 30 years and was dose-respondent, and an earlier age at first breastfeeding was further associated with increased protection.

Modugno, F, Goughnour, S, Wallack, D, et al, (2019). Breastfeeding factors and risk of epithelial ovarian cancer. Gynecologic Oncology 2019 January 25

The fraction of cancer attributable to modifiable risk factors in England, Wales, Scotland, Northern Ireland, and the United Kingdom in 2015

This study explored the fraction of cancer cases attributable to modifiable risk factors in the UK, finding that nearly four in ten (37.7%) cancer cases in 2015 in the UK were attributable to known risk factors. Researchers identified not breastfeeding as one such risk factor; amongst women, not breastfeeding was attributed to 2,582 cancer cases in 2015.

Brown, K, et al, (2018). The fraction of cancer attributable to modifiable risk factors in England, Wales, Scotland, Northern Ireland, and the United Kingdom in 2015, British Journal of Cancer, doi:10.1038/s41416-018-0029-6.

Older research 

• Lambertini, M, et al (2016). Reproductive behaviors and risk of developing breast cancer according to tumor subtype: A systematic review and meta-analysis of epidemiological studies, Cancer Treatment Reviews, doi: 10.1016/j.ctrv.2016.07.006
• Lööf-Johanson, M (2016). Breastfeeding Associated with Reduced Mortality in Women with Breast Cancer, Breastfeeding Medicine, doi:10.1089/bfm.2015.0094
• Sung, HK, et al (2016). The Effect of Breastfeeding Duration and Parity on the Risk of Epithelial Ovarian Cancer: A Systematic Review and Meta-analysis, Journal of Preventative Medicine and Public Health, DOI: 10.3961/jpmph.16.066