If the patient does not have vaginal itching before coitus, and every time after coitus, vaginal itching occurs, there are two main possibilities to consider, and to deal with the cause: first, if the patient every time the use of condoms coitus, it is considered that the patient may be allergic to condoms and caused. So in this case to change another brand of condoms, or directly use the intrauterine placement of the birth control ring, take a compound short-acting contraceptive pill to contraception. Secondly, it is considered that the male penis carries pathogenic bacteria, which are transmitted to women after intercourse, and cause vaginal inflammatory diseases in women, which leads to itching. Patients need to do gynecological internal examination, at the same time do the leukorrhea test, to determine the type of inflammation after systematic treatment. While the woman is undergoing treatment, the man should also undergo active treatment and should not have intercourse during the treatment period.