Breast swelling and pain with hard lumps may be normal physiological reasons, but may also be due to breast hyperplasia or mastitis and other reasons. 1. Physiological reasons: before and after menstruation or during pregnancy and breastfeeding, due to changes in hormone levels in the body, it will lead to the formation of hard lumps in the mammary glands, accompanied by a feeling of swelling and pain, which is a normal physiological phenomenon. 2. Mammary gland hyperplasia: usually related to the patient’s endocrine hormone metabolism imbalance, due to the body’s estrogen level increases, will produce persistent stimulation of the mammary glands, resulting in breast tissue hyperplasia changes, breast swelling and pain with hard lumps of the situation. 3. Mastitis: It occurs in breastfeeding women, usually due to breastfeeding women do not breastfeed in time, resulting in a large amount of milk stagnation in the mammary glands, and combined with bacterial infections caused by the symptoms of breast swelling and pain with hard lumps. If you have a hard lump in your chest, it is recommended that you go to the hospital in time to have a thorough examination to determine the cause of the problem and then give targeted treatment to avoid delaying the treatment and further aggravation of the condition.