Is it normal to have a stomach ache before the onset of your period? If there is pain, the pain is not severe and can be tolerated, it is usually not too abnormal. When the pain is particularly severe and intolerable, it may be caused by certain gynecological diseases, then it is not normal. Menstruation is due to the cycle of endometrial stripping caused by uterine bleeding, when the endometrial lining is ready to strip, must be caused by uterine contraction, when the uterine contraction, some more sensitive women can appear in the period or menstruation before the pain in the lower abdomen, this pain is mostly tolerable, with the onset of menstruation, menstrual blood discharged, the pain is gradually alleviated, relieved. For secondary, that is, in the past before menstruation does not hurt, but after menstruation for more than ten years, there is secondary pain in the stomach before menstruation, which may be related to the occurrence of some diseases, such as endometriosis, so when the pain is intolerable, the original did not have now have this kind of pain in the stomach before menstruation, it is recommended that we go to the hospital to do a checkup, to determine whether it is normal, whether there are diseases, and whether to do treatment. It is also recommended that you go to the hospital for a checkup to determine if it is normal, if there is a disease, and if treatment should be done.