Girls chest pain usually consider the following aspects of the cause: the first aspect, there may be due to middle-aged women work pressure or life stress, emotional fluctuations, and the hormone level changes. Or in the pre-menstrual period and menstruation, the body’s hormone levels with the menstrual cycle continues to change to a higher level, when the mammary glands are stimulated by estrogen, so it will produce a sense of swelling and pain, and this pain usually disappears with the end of menstruation. The second aspect is that there may be breast tumors or lumps. Breast cancer or breast cysts are usually considered, which are caused by a variety of factors, such as family genetics, environmental factors, and the patient’s personality and emotions. The third aspect to consider is that there is mastitis, usually unmarried women are not easy to get, while married women, especially during the breastfeeding period, due to the lack of attention to hygiene, or not timely sucking the excess milk out of the mammary glands, it will lead to mastitis, the symptoms of redness, swelling, heat and pain.