#parity

#parity

Parity and breastfeeding reduce the risk of breast cancer, particularly triple-negative breast cancer (TNBC)1,2, yet the immunological mechanisms underlying this protection remain unclear. Here, we show that parity induces an accumulation of CD8+ T cells, including cells with a tissue-resident memory (TRM)-like phenotype within human normal breast tissue. In murine models, pregnancy followed by lactation and involution drove the accumulation of CD8 T