The 51-year-old menstrual stomach pain is considered to be related to cold, hormone level changes, endometriosis and so on. 1. Cold: women who crave cold drinks or rain and water before menstruation will easily lead to poor uterine blood flow, which will stimulate the uterus to contract and abdominal pain, generally to be smooth flow of menstrual blood out of abdominal pain can be relieved. 2. Hormone level changes: after a woman’s period, due to changes in estrogen, progesterone, prostaglandins and other hormone levels, so women may also have a slight abdominal pain, usually to be cleaned up by menstruation can be relieved on their own. 3. Endometriosis: For women with dysmenorrhea, the first thing to do is to exclude the possibility of organic diseases such as endometriosis, due to the active endometrium planted in the uterine myometrium or other organs or tissues on the surface, along with the ovarian cyclic changes, the ectopic endometrium will also have bleeding and other changes, so it will cause progressive aggravation of dysmenorrhea. For 51-year-old women with menstrual pain in the stomach, it is recommended that they go to the gynecology department of a regular hospital to improve the ultrasound and other relevant examinations, to clarify the cause of the disease and then under the guidance of the doctor active treatment.