Yellow vaginal discharge is often caused by the following reasons: First, inflammation of the vagina, such as trichomonas infection, can lead to yellow and foamy discharge, accompanied by itching of the vulva, it is recommended to check the routine leucorrhea, according to the results, you can give compound metronidazole to the vagina and oral metronidazole tablets for treatment. Second, due to chronic inflammation of the cervix, this yellow watery leucorrhea is mixed with thick mucus filaments, so it is recommended to give oral anti-cervical inflammation tablets and do cervical cancer screening. Thirdly, cancer of the endometrium or inflammation of the endometrium, ultrasound examination is recommended to understand the thickness of the endometrium and whether there is echogenicity, and if necessary, diagnostic scraping is recommended. Fourthly, cancer of the fallopian tubes may also cause a large amount of yellow plasma-like discharge from the vagina, and ultrasound examination is recommended to find out whether there is a mass in the adnexal area.