Breast-feeding reduces the risk for certain types of breast cancer, according to a study conducted at Columbia University’s Mailman School of Public Health. The study also found that having three or more children without breast-feeding was associated with an increased risk for what’s called estrogen receptor- and progesterone receptor- (ER/PR) negative breast cancer. ER/PR-negative breast cancer often affects younger women and has a poor prognosis.
“Women who had children but did not breast-feed had about 1.5 times the risk for ER/PR-negative breast cancer,” says researcher Meghan Work. “If women breast-fed their children, there was no increased risk for ER/PR-negative cancer. This is particularly important as breast-feeding is a modifiable factor that can be promoted and supported through health policy.”