Breast pain is considered to be caused by breast hyperplasia. The etiology of breast hyperplasia is not yet very clear. Currently, it is mostly believed to be related to elevated levels of estrogen due to endocrine disorders. Some also attribute it to external environmental factors, work, living conditions, and various stressors causing changes in the internal environment, which in turn affect the function of the endocrine system, leading to abnormal secretion of one or more hormones. Additionally, some scholars believe that it is related to differences in the quality and quantity of female hormone receptors in the breast tissue, leading to varying degrees of proliferation in different parts of the breast.