Nothing is more painful for patients with adenomyosis than menstrual cramps. Why do menstrual cramps occur? This can be explained by the principle of the development of adenomyosis. The pathogenesis of adenomyosis is the escape of normal endometrial cells from the normal endometrial area to the inner muscles of the uterus, the myometrium. Since these endometrial cells have the characteristic of periodically shedding and causing bleeding, i.e. menstruation, when during menstruation it also causes bleeding, but at this time they are between the muscles of the uterus, the blood cannot flow into the uterine cavity into the vagina to form menstrual blood like in the tissue of the endometrium, it has to squeeze between the muscles of the uterus, making the uterus enlarged and destroying the muscles of the uterus, at this moment, the enlarged uterus causes the patient The enlarged uterus causes severe menstrual pain. When the period is over, the enlarged uterus improves and the patient’s dysmenorrhea improves and is relieved. However, because of the cyclic nature of these cells, when the next menstruation occurs, the dysmenorrhea reappears, week after week, while the uterus is getting worse one at a time, and the uterus is being damaged one at a time, and the uterus is getting bigger and bigger. Therefore, the patient feels only a little discomfort at the beginning of the disease, and as the disease becomes more severe, the dysmenorrhea becomes more and more severe, while the duration of the dysmenorrhea extends from being limited to the 2nd-3rd day of the period to the whole period, and in severe cases, the pain remains before and after the period, requiring painkillers or even the use of extremely powerful painkillers such as dulcolax for pain relief. Therefore, although adenomyosis is a benign disease, the pain caused to the patient is no less than that of a malignant disease.