A level of 35 units per milliliter or less is a normal result for CA 125 testing, according to Mayo Clinic. Levels higher than this do not necessarily indicate that the patient has cancer as many benign conditions, such as pregnancy and menstruation, can result in elevated CA 125 levels.
CA 125 is a protein that occurs in high levels on the surface of ovarian cancer cells, says WebMD. Elevated levels may indicate the presence of ovarian, fallopian tube, endometrial or peritoneal cancer. Doctors test for the levels of CA 125 to monitor patients diagnosed with ovarian cancer or to screen high-risk individuals for the development of the disease, states Mayo Clinic.