It is rare for women to have blue discharge in their underwear, and it is necessary to rule out whether the color of the underwear comes off, causing staining of the discharge, or it may be vaginal inflammation, resulting in abnormal discharge. Because women’s normal leukorrhea should be egg white, when there is inflammation and infection, it is more common to appear yellow discharge, or yellow-green color discharge, blue discharge is not appear, need to be through the routine examination of leukorrhea, whether there is vaginal inflammation. Common vaginal infections include bacterial infections, trichomonas infections, and mold infections, which can be treated with medication according to the test results. If the results of the routine examination of leukorrhea are normal, it is very likely that the staining of secretions is caused by the loss of color in the underwear, which can be improved by washing the underwear or wearing white cotton underwear, and observing whether the abnormality still exists.