First, nipple injury, when external force directly or indirectly acts on the nipple, it can cause local nipple injury and acute inflammatory changes, which are manifested as nipple swelling and pain and discomfort.
Second, breast cystic hyperplasia, due to the increase of estrogen level in the body, which induced an acute attack of breast cystic hyperplasia, manifested as increased breast pain, and can spread to nipple pain.
Third, acute mastitis, which mostly occurs in lactating women, is an acute purulent infection of the breast. The clinical manifestations are redness, swelling, heat and pain of the breast, and there may be pus overflow from the nipple and nipple pain. Therefore, if nipple pain caused by nipple injury can be ruled out, breast color Doppler ultrasound examination should be carried out in time to identify breast lesions, and reasonable treatment should be carried out under the guidance of specialists.