The cessation of menstruation after sexual intercourse during menstruation should be considered to be caused by contraction of the uterus and amenorrhea, or by infection of the uterine cavity and gynecological inflammation. Sex during menstruation is a very incorrect behavior and is a risky sexual behavior. The women’s resistance is poor during menstruation, the cervix is open, more likely to lead to disease or infection, causing cervicitis, pelvic inflammatory, endometritis and other gynecological infections and sexually transmitted infections, serious and may lead to infertility. Therefore, for the health of both parties and reproductive health, it is better to have intercourse 3 days after the end of menstruation. If menstruation disappears due to sex, it is recommended to seek medical examination in time to clarify the specific reasons for disappearance and then treat the problem.