If the leucorrhea is yellow, it is clinically abnormal and is commonly caused by the following reasons: First, inflammation of the vaginal mucosa, which can lead to yellow vaginal discharge and may cause local discomfort in the vulva or a burning sensation at the vaginal opening. Secondly, local inflammation of the cervix, when there is local inflammation of the cervix, yellowish leucorrhea may appear, and this leucorrhea is relatively viscous, occasionally accompanied by blood, and clinically it may also manifest as pain in the lumbosacral area. Third, the pelvic inflammatory disease caused by, when the pelvic inflammatory disease, will often make increased exudation, will lead to yellowing of the leucorrhea. Fourthly, if there is inflammation of the endometrium, it will also cause yellowing of the leucorrhea, often accompanied by the possibility of dysmenorrhea.