High tumor antigen CA125 during menstruation may be a normal physiological phenomenon, or it may be caused by diseases, such as inflammatory diseases or tumor diseases. 1. Physiological phenomenon: during menstruation or breastfeeding, women tend to have a slightly higher tumor antigen CA125, but the degree of increase is not large, and it is often lower than 100U/ml. 2. Inflammatory diseases: for example, acute pelvic inflammatory disease, women may lead to CA125 increase, especially during menstruation, the increase will be more obvious. 3. Tumor diseases: most commonly found in ovarian chocolate cysts, endometriosis, ovarian cancer can lead to increased CA125, but also may be liver cancer. If the tumor antigen CA125 is high during menstruation, if there are no other uncomfortable symptoms, there is no need for special treatment. After menstruation, you can go to the hospital for rechecking, and if the result of the test is still high, you need to clarify the cause and target treatment.