No harm to women. If you have sex during menstruation, it will do harm to women. "Men often can't stand abstinence for a long time after marriage, so they occasionally ask their wives to have sex with him during menstruation. Generally speaking, because women are worried about dirty sheets, men are afraid of seeing blood and rarely have sex during menstruation, and most of these people want to challenge tradition, break taboos and look for excitement. Pay attention to the following points during menstrual sexual intercourse. 1. orgasm will promote uterine contraction, so if you have sex in the first half of menstruation, it will cause a lot of bleeding, leading to dirty sheets. 2. During sexual intercourse, men should use condoms (female menstrual secretions enter male urethra, which will cause male urethral irritation). In addition, because there is blood, the lubricity in the vagina is greatly reduced, and intense sexual intercourse may cause inflammation and swelling of the female vaginal opening. 3. If the menstrual period is still sexual intercourse as usual, the exfoliated endometrium can not only be discharged from the vagina, but also may be pressed back into the abdominal cavity, which becomes the inducement of endometriosis. Some people use anal sex instead of normal sexual intercourse during menstruation. If so, we should pay special attention to health problems. 5. In the second half of menstruation, if the blood volume is less, it should be fine. However, if women use sanitary cotton swabs, they should take them out first, otherwise they will be pushed deep into the uterus because of sexual intercourse and rot here, and things will be serious, so be more careful. 6. Sleeping in the same room during menstruation may lead to infertility. Because the sperm meets the overflowing blood cells at the damaged part of the endometrium, and even enters the blood, it can lead to mid-term immune cell allergy and stimulate the body to produce anti-sperm antibodies, which can exist in female cervical mucus and serum. Once the sperm antibody comes into contact with sperm again, it will stimulate the immune rejection of the body, thus affecting the combination of sperm and eggs. " Note: Try to avoid sexual life during menstruation.