Itching of the vulva after sexual intercourse is due to the occurrence of local infections and the stimulation of sexual intercourse, which leads to an increase in vaginal secretions and thus stimulates the local area, which, together with the lack of timely local cleaning, leads to local itching. The most common vaginal infection that occurs through sex is trichomoniasis, followed by bacterial vaginitis. Most women experience increased leucorrhea, odor and other discomforts. You should pay attention to cleanliness before and after sex and perform local cleaning in a timely manner, but you should avoid douching to avoid bringing pathogenic bacteria into the vagina. If necessary, sexual partners should be treated at the same time to avoid repeated infections.