Trichomonas vaginitis in late pregnancy may be related to vaginal flora dysbiosis during pregnancy, exposure to contaminated equipment, and poor lifestyle habits. 1. Imbalance of vaginal flora during pregnancy: when pregnant women are in gestation, due to the local immune environment of pregnant women’s vagina is at a lower level, the vaginal PH value changes, leading to a significant reduction in the vaginal defense ability of pregnant women, increasing the risk of trichomoniasis. 2. Contact with contaminated equipment: trichomoniasis, infectious. Late pregnancy vulvar tissue nutrient supply is limited, resulting in vulvar environmental resistance is reduced, pregnant women who have contact with contaminated public facilities, such as toilets, swimming pools, bathtubs, hot springs, etc., or in the pregnancy checkup, contact with not disinfected thoroughly contaminated medical checkup tools, may be infected with trichomoniasis. 3. Bad living habits: not paying attention to local cleansing of the vulva can easily cause damage to the vaginal micro-ecosystem, reducing the self-cleaning ability and resistance of the vagina to Trichomonas, increasing the chances of infection. Once the existence of trichomoniasis is diagnosed, it is recommended to prevent and control the disease under the guidance of a professional doctor as soon as possible to avoid adverse consequences.