Some women may experience breast swelling and pain a week or so before their menstrual period, but there are also some cases of breast swelling that have nothing to do with menstruation and need to be identified. Before menstruation, some women may experience breast swelling and pain, headache, fatigue, nervousness and general weakness, and even abdominal pain, diarrhea, etc. Generally speaking, these are normal phenomena, due to changes in hormone levels in the body, without excessive worry. With the onset and end of menstruation, the above symptoms will gradually disappear. However, some breast disorders such as acute mastitis, breast hyperplasia, etc. may also cause swelling of the breasts, which has little to do with menstruation, so it is recommended to go to the breast surgery department in time to get a specific diagnosis. It is recommended to pay attention to physical exercise, strengthen resistance, underwear size should be appropriate and change frequently, pay attention to personal hygiene. Regular health checkups should be done every year so that problems can be detected and dealt with as soon as possible.