It is normal to be able to express milk even after one month of weaning. The ability to produce milk during pregnancy or breastfeeding is due to the prolactin in the body. After giving birth, prolactin in a woman’s body gradually decreases, but it is still higher than the average person. If weaned, some women’s prolactin will drop to normal levels within two weeks. However, many postpartum women can express a small amount of milk for six months to a year, which is normal and nothing to worry about. However, if you can still express milk for too long, you cannot exclude disease factors, such as mastitis, milk duct overflow or breast cancer, which may have white, yellow or bloody fluid. It is often accompanied by some symptoms, such as breast swelling, swelling and tingling, cracked and swollen nipples, and cancer manifests with skin changes of the breast, such as the appearance of pits.