It is generally recommended not to have intercourse during the period because during menstruation the woman’s pelvic cavity is congested and her resistance is low, so it is easy to get infected, so it is generally recommended not to have sex during the menstruation period. If you have sex during menstruation and have semen ejaculated into it, it is easy to cause an upward infection because the semen may carry some bacteria, and during menstruation there is a trauma in the endometrium, and at the same time, there is pelvic congestion, the entry of sperm is sometimes easy to cause an infection, that is, to cause an upward infection. When the endometrial wound encounters bacterial infection, it is easy to spread, resulting in endometritis and tubal inflammation, causing obstacles to future pregnancy.