These major studies provide robust evidence on the links between breastfeeding and a range of maternal health outcomes.
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.
Suboptimal breastfeeding in the United States: Maternal and pediatric health outcomes and costs
This study into the impact of suboptimal breastfeeding in the United States found annual excess deaths attributable to suboptimal breastfeeding totalled 3,340, 78% of which were maternal due to myocardial infarction, breast cancer and diabetes. Excess pediatric deaths totalled 721, mostly due to Sudden Infant Death Syndrome (SIDS) and necrotizing enterocolitis (NEC). Researchers found that for every 597 women who optimally breastfeed, one maternal or child death was prevented. They noted that breastfeeding has a larger impact on women’s health than previously appreciated, and that policies to increase optimal breastfeeding could result in substantial public health gains.
The Lancet breastfeeding series
This powerful series presents resounding evidence that breastfeeding protects health, saves lives and cuts costs in every country worldwide. It finds that women are not getting the support they need to breastfeed, and that breastfeeding success is the collective responsibility of society. It demonstrates that the Baby Friendly Initiative is highly effective in improving breastfeeding practices, and that increasing breastfeeding worldwide could prevent over 800,000 child deaths every year.
Special issue on the impact of breastfeeding
This supplement to Acta Paediatrica (coordinated by the World Health Organisation and funded by the Gates Foundation) presents a series of meta-analyses and systematic literature reviews examining a variety of health effects potentially related to breastfeeding.
Breastfeeding and maternal health outcomes
This review supports the hypothesis that breastfeeding is protective against breast and ovarian carcinoma, and exclusive breastfeeding and predominant breastfeeding increase the duration of lactational amenorrhoea. There is evidence that breastfeeding reduces the risk of type 2 diabetes. However, an association between breastfeeding and bone mineral density or maternal depression or postpartum weight change was not evident.
Chowdhury, R. et al (2015). Breastfeeding and maternal health outcomes: a systematic review and meta-analysis. Acta Paediatrica, Special Issue: Impact of Breastfeeding on Maternal and Child Health. Volume 104, Issue Supplement S467, pages 96-113.
Breastfeeding and health outcomes in developed countries
A review from the USA investigated the effects of breastfeeding in developed countries. The reviewers concluded that a history of breastfeeding was associated with a reduction in the risk of acute otitis media, non-specific gastroenteritis, severe lower respiratory tract infections, atopic dermatitis, asthma (young children), obesity, type 1 and 2 diabetes, childhood leukaemia, sudden infant death syndrome (SIDS), and necrotizing enterocolitis (NEC). For maternal outcomes, a history of lactation was associated with a reduced risk of type 2 diabetes, breast, and ovarian cancer. Early cessation of breastfeeding or not breastfeeding was associated with an increased risk of maternal postpartum depression.
Related studies and further reading
The Lancet: Increasing breastfeeding worldwide could prevent over 800,000 child deaths every year