If itching occurs after each intercourse, it is considered to be caused by sperm allergy. It is recommended to use condom during the whole process of sexual intercourse to avoid contact between sperm and vaginal mucosa, which may cause allergic reaction. Oral dexamethasone can also be taken for treatment, during the treatment period when having sex, it is recommended to use a condom, and then consider sex without a condom after stopping treatment. To rule out vaginal inflammation caused by itching, it is recommended to do routine tests, if necessary, can do mycoplasma and chlamydia examination, mainly to understand the vagina there is no pathogenic bacterial infections, such as mold, trichomonas, mycoplasma, chlamydia can cause vulvar itching.