Breast pain and swelling when you are about to get your period is often caused by endocrine disorders, such as more estrogen secretion and less progesterone secretion, which can cause localized breast swelling and pain. The reason why endocrine disorders are caused is related to frequent late nights, irregular life, emotional changes or frequent symptoms of anxiety, all of which can lead to endocrine disorders and localized breast swelling and pain. Therefore, it is recommended that women maintain a good state of mind in daily life, keep a happy mood, and do not stay up late, and must be regular in life, and do not smoke and drink excessively, which will have less impact on women’s endocrine secretion and significantly reduce the premenstrual breast swelling and pain.