You should not have intercourse during menstruation because when you have your period, the endometrium sheds a certain amount of menstrual blood and the cervical opening is open, so if you have intercourse, the male partner’s genitals will have certain bacteria and cross-infection will occur. At the same time, since the fallopian tube and the uterus are connected, the endometrial lining of the uterus will contain certain bacteria during intercourse, which will enter the pelvic cavity with the fallopian tube, causing tubitis, endometritis, pelvic inflammatory disease, and even adenomyosis of the uterus, causing chocolate cysts to occur. If you have intercourse during menstruation, it can also cause dripping menstruation, abdominal pain and high fever. It is forbidden to have intercourse when you have your period, and you should pay attention to personal and mutual hygiene, wash your vulva every day, change your underwear every day, and change your sanitary napkin once every four hours to avoid inflammation.