Trichomonas vaginalis is a common form of vaginitis that is caused by Trichomonas. Trichomonas vaginalis, Trichomonas humana and Trichomonas oralis are parasitic on the genitourinary system, intestinal tract and oral cavity, respectively. Trichomonas vaginalis is associated with skin diseases and is prone to trichomoniasis. Trichomonas vaginalis is a parasitic disease transmitted mainly through sexual intercourse and is contagious. Symptoms of trichomoniasis: 25-50% of patients with trichomoniasis are asymptomatic at the beginning of the infection. The main symptoms are increased vaginal discharge and vulvar itching, with occasional burning, pain, and painful intercourse. The discharge is typically thin, purulent, yellowish-green, foamy, and smelly. The purulent discharge is due to the presence of white blood cells in the discharge, while the yellowish-green, foamy, foul-smelling discharge is due to the anaerobic fermentation of sugars by trichomonads, which produces putrid gas. Itching is mainly at the vaginal opening and vulva. In combination with urinary tract infections, there may be frequent and painful urination and sometimes hematuria. Trichomonas vaginalis can engulf sperm and prevent lactic acid production, which can affect sperm survival in the vagina and lead to infertility. In severe cases, there are scattered bleeding spots and even bleeding spots on the cervix, forming a “strawberry-like” cervix. There is a lot of leukorrhea in the posterior fornix, which is grayish yellow, yellowish white thin liquid or yellowish green purulent discharge, often foamy. The vaginal mucosa is not abnormally changed in those with worms.