It is not recommended to have intercourse immediately after menstruation, but 2 to 3 days after menstruation. If you have intercourse immediately after menstruation, the endometrium has not yet returned to normal, or there is still residual blood in the vagina, so intercourse at this time is likely to cause cross-infection and may result in continuous bleeding and abdominal pain or high fever. As far as possible, intercourse should take place 3 days after the end of menstruation, when the endometrium has returned to normal and intercourse is possible. When having intercourse, try to wash the genitals of both partners to avoid vaginitis caused by cross infection. At the same time, if you are not planning to get pregnant, you must use condoms to prevent unwanted pregnancies that may require termination of pregnancy, which may also cause damage to the uterus, including the endometrium, so as not to affect future pregnancies.