Breast enlargement during lactation is a breast disease that occurs in many new mothers. It is a disease of endocrine disorders and its main symptom is characterized by periodic pain in the breast. The pain is initially characterized by diffuse swelling, and tenderness is obvious in the upper outer and upper middle part of the breast. The pain increases before menstruation each month, and decreases or gradually disappears after menstruation. Severe breast enlargement during lactation has persistent pain before and after menstruation. Sometimes the pain may radiate to the armpits, back of the shoulders, and upper limbs. The actual fact is that you should not only improve your own immune resistance, but also have a correct understanding of the problem of breast enlargement, always keep yourself optimistic and in a good mood, and carry out targeted comprehensive treatment. Since there is no exact understanding of the pathogenesis and causes of breast enlargement during lactation, treatment is basically symptomatic, but it often brings certain side effects. It should be pointed out here that for patients with serious breast hyperplasia, once a lump with rapid growth or hardening texture is found within a short period of time, the possibility of cancer should be highly suspected, and if necessary, biopsy or simple excision of the affected breast should be performed, and if cancer cells are found in the frozen section during surgery, the patient should be treated as breast cancer.