Vaginal itching after coitus has the following reasons: First, before or after coitus did not adequately clean the genitals of both sides, there will be a certain amount of urine, circumcision, as well as vaginal secretions caused by cross-infection; second, coitus if one side of the allergy to the condom can also cause allergic vaginal itching; third, the male circumcision is longer, it will be intermingled with the bacterial, there will be vaginal itching symptoms occur; Fourth, the woman’s body immunity is poor, weak and hormone level changes, will make the vaginal flora environment changes, then may be due to vaginal flora disorder caused by vaginal inflammation, resulting in vaginal itching, it is recommended that the gynecology department of a professional hospital for the vaginal micro-ecological examination, according to the specific circumstances to decide whether to use medication.