Immediately after menstruation coitus may cause uterine bleeding, the phenomenon of bleeding again, easy to lead to women’s vaginal bleeding for a long time. The immune system of women just after menstruation is relatively low, poor resistance, male genitals bring bacteria into the female genitals, easy to cause infection leading to the occurrence of inflammation. The new uterine lining is not yet developed after menstruation, and coitus at this time is very harmful to women’s bodies, easily leading to gynecological diseases. Due to sexual stimulation during coitus, the uterus will contract, and the endometrial debris shed in the uterine cavity will enter the fallopian tubes, abdominal cavity and pelvis, triggering endometriosis. It is also easy to experience abdominal pain when having intercourse, as it is very irritating to the body. It is best to have intercourse three days after the menstrual period, when the development of the new endometrium is completed and the woman’s body is back to normal, so there is no adverse effect on intercourse. But pay attention to coitus hygiene, wash before and after coitus to avoid breeding bacteria lead to gynecological diseases.