There are many reasons for stomach pain without menstruation, which may be a normal physiological phenomenon, or it may be related to pelvic inflammatory disease, pregnancy, adnexal cysts or acute appendicitis, acute gastroenteritis and other factors. 1. Physiological phenomenon: mainly seen in ovulation pain and menstrual pain, usually with the end of ovulation and menstruation, abdominal pain symptoms will gradually ease. 2. Pelvic inflammatory disease: If there is inflammation in the pelvis, due to the inflammation stimulation, it can cause the symptom of stomach pain without menstruation. 3. Pregnancy: If the menstrual cycle is usually regular, and the menstrual period stops for more than 10 days, the possibility of pregnancy should be considered. In this case, there may also be some diseases related to pregnancy, such as ectopic pregnancy or early pregnancy abortion. 4. Adnexal cysts: If a woman has an adnexal cyst, and it is larger than the size of the adnexal cysts or torsion occurs, it can also cause stomach pain without menstruation. 5. Acute appendicitis, acute gastroenteritis and so on: of course, there may be no relationship with the female reproductive system diseases, is due to acute appendicitis, acute cholecystitis or acute gastroenteritis and other related diseases. If the above symptoms occur, the patient should pay attention, do not delay the condition, it is recommended to go to the hospital in a timely manner to determine the cause of the disease and follow the doctor’s instructions for standardized treatment, to prevent further aggravation of the condition, endangering the health of the body.