The vast majority of women who have menstruation will experience slight swelling and pain in the lower abdomen, but it does not affect their daily work and life. If dysmenorrhea affects work and life, it is mainly due to the following reasons: 1. When menstruation occurs, it is the shedding of the uterine lining that causes vaginal bleeding, which produces a large amount of prostaglandins and causes the uterine smooth muscle to contract, and so it leads to stomach pain.2. Endometriosis. The endometrial cells with activity are planted in locations other than the uterine cavity, so when menstruation occurs, the foci of ectopic disease will also bleed, which will lead to dysmenorrhea.3, uterine developmental abnormalities, which can cause dysmenorrhea, and pelvic inflammation, which can also lead to dysmenorrhea. Therefore, dysmenorrhea is caused by relatively complicated reasons, and it is necessary to do examinations and then find out the causes in order to treat the symptoms.