Milk flowing out of its own accord is considered to be overflowing, and a distinction needs to be made between pregnant women and non-pregnant women. Because the secretion of milk is mainly regulated by the body’s lactogen, when the body’s lactogen is abnormally elevated, the phenomenon of overflowing milk is likely to occur. For unmarried and infertile women, the symptoms may be related to hormone levels, pituitary tumors, precocious puberty, abnormal luteal function, and drug use. If there is abnormal elevation of prolactin, it can be controlled by using bromocriptine. At the same time, breast ultrasound is needed to check whether there is any obvious abnormal lesion in the breast and treat the symptoms according to the test results. There are some medications that can cause breast overflow after use, such as chlorpromazine, which can recover on their own after discontinuing the medication. For women during pregnancy it is a normal phenomenon of hormone level changes in the body.