The phenomenon of hard lumps in the breasts with pain during breastfeeding may be mastitis or breast tumor and other diseases. The development of mammary gland lobules is very perfect during the breastfeeding period, and under the action of lactogen, the milk is secreted continuously. If you don’t suckle in time, the milk will be stagnated in the breast to form a hard lump, which is swollen and painful to the touch. If there is an infection at this time, it will develop into mastitis, which can be accompanied by high fever and other symptoms. In this case, you should apply appropriate hot compresses, and then massage under the guidance of a professional doctor to reduce the blockage of the milk ducts, increase the frequency of breastfeeding or use a breast pump to suck out. If the symptoms do not get better and the pain worsens, you should consult a doctor and get treatment according to the doctor’s advice. If there is a lump in the breast, the possibility of breast tumor should also be ruled out. If the patient has a hard lump in the breast with pain during breastfeeding, it is recommended to consult a doctor in time to avoid delaying the condition.