You can have sex after your period clears. Menstruation is a special physiological period for women, a period of poor body resistance, while the pelvic cavity is also in a state of congestion. There are two main reasons why sex is prohibited at this time: 1) to prevent retrograde infection, and 2) to prevent pelvic endometriosis caused by the reflux of menstrual blood. If there are no other special circumstances after menstruation, you can have sex, and if there is no requirement for childbirth, contraception is recommended. Relatively speaking, if there is no fertility requirement within a year or if there is already no fertility requirement, patients can consider wearing a birth control device. If there is no need to have children for a short period of time, temporary contraception can be considered as oral short-acting contraceptive pills or external condoms, both of which are safe and effective.