Fortner RT, et al. - In the Nurses’ Health Study (NHS; 1976–2012) and NHSII (1989–2013), researchers ascertained parity, breastfeeding, and breast cancer risk according to hormone-receptor (estrogen and progesterone receptor) and molecular subtypes (luminal A, luminal B, HER2-enriched, and basal-like). They analyzed a total of 199,514 women; 12,452 (ER+ n = 8,235; ER− n = 1,978) breast cancers were diagnosed in these women. As per observations, there appeared an inverse association between breastfeeding and hormone receptor-negative breast cancers, adding to the established benefits of breastfeeding. It represents an accessible and cost-effective risk-reduction strategy for aggressive disease subtypes.