CA125 is increased in endometriosis. In patients with common ovarian chocolate cysts and adenomyosis, CA125 is found to be significantly increased when checking tumor markers, especially in ovarian chocolate cysts CA125 will mostly exceed 100 U/mL or more, and the more severe the endometriosis, CA125 is slightly higher, but increased CA125 is not specific for endometriosis. There is no specificity. Many causes can cause CA125 to increase, such as pelvic inflammatory disease liver disease can cause CA125 to increase. Therefore, identification should be based on clinical symptoms as well as ancillary tests. CA125 levels are mostly used clinically to monitor endometriosis, lesion activity and to monitor the efficacy and recurrence of the disease, which is more clinically valuable for diagnosis and treatment; CA125 will decrease when the treatment is effective and increase when the disease recurs.