Breastfeeding can reduce the risk of developing breast cancer.
Most women who breastfeed experience hormonal changes during lactation that delay their menstrual periods. This reduces a woman’s lifetime exposure to hormones like estrogen,which can promote breast cancer cell growth
Sources:
https://www.mdanderson.org/publications/focused-on-health/breastfeeding-breast-cancer-prevention.h19-1589046.html
https://www.ncbi.nlm.nih.gov/pubmed/12133652?dopt=Abstract
