Discomfort on one side of the breast is a relatively common clinical condition. Generally include the following causes: first of all, it may be due to work pressure, or fatigue, lack of sleep caused by breast hyperplasia, most of this situation will appear some uncomfortable feeling, especially during menstruation or menstruation, the symptoms of breast swelling and discomfort will be significantly aggravated, with the change of menstruation disappeared or completely relieved. There is also a situation where one side of the breast may be squeezed during sleep, which causes poor local blood circulation and may also lead to some blood circulation disorders, resulting in some breast symptoms. Therefore, if you feel uncomfortable on one side, it is best to go to a regular hospital for a detailed examination. After finding the exact cause of the problem through color ultrasound, systematic and standardized treatment and prevention will be carried out to address the cause.