The pain under the left breast of pregnancy may be caused by the enlargement of the uterus and the pulling of the ligaments supporting the uterus, or it may be caused by the pulling of the distended breasts. Pay attention to any symptoms of nausea and vomiting, and it is recommended to have an ECG examination and gynecological ultrasound. If the examination is normal, there is usually nothing wrong. If accompanied by nausea, vomiting, pay attention to whether the gastrointestinal tract inflammation caused, pay attention to drink more water, eat light and easy to digest food, prohibit cold and stimulating food. Keep your mood happy, do not sulk, and pay attention to rest, less bending, lifting heavy objects, minor pain sometimes need to rest a few days will be good. You can also apply local hot compresses and try not to apply medication. If the pain is heavy, you need to go to the hospital immediately to see a doctor to prevent miscarriage.