The symptom of nipple pain before menstruation is a manifestation of premenstrual syndrome. The cause of the symptoms is related to changes in the function of estrogen and progesterone secreted by the ovaries before menstruation, which affects the blood supply to the breasts, as well as to the increased sensitivity of local nerves. Women suffering from breast enlargement, breast cysts, breast fibroids and other diseases may also experience significant nipple pain and breast swelling before the onset of menstruation. If there are more bad habits in daily life, such as excessive mental tension, stress, frequent consumption of overly oily and spicy stimulating foods, frequent wearing of tight underwear, frequent squeezing and stimulation of the breasts, it may also cause the symptoms of nipple pain before menstruation. Mild pain symptoms do not have a major impact, but severe pain symptoms may have organic diseases and should be treated by a timely hospital visit to identify the cause.