Patients may experience breast swelling and pain after taking progesterone tablets. Because the main ingredient in progesterone tablets is progesterone, progesterone can stimulate the patient’s breast ducts, resulting in dilation of breast ducts or physiological hyperplasia, in which case breast swelling and pain can occur. If the patient is to adjust her menstruation, the breast swelling and pain can be left untreated when it is mild; if the breast swelling and pain is more serious, the patient can choose to treat with Chinese herbal medicines such as Chai Hu Shu Liver Granules, Zhuan Yao Wan, Dispersing Nodules and Analgesic Capsules, Xia Ku Cao, etc. These Chinese herbal medicines have the effects of draining the liver, regulating Qi, activating blood circulation and relieving pain, which are very effective in treating the breast swelling and pain caused by this condition. If the patient is used for fetus preservation treatment, when the pain is relatively mild, it can be left untreated; if the pain is more severe, it proves that the progesterone level in the patient’s body is OK, the blood can be checked to observe the specific level of progesterone in the patient, and the drug can be selected to reduce the dosage according to the specific situation.