Menstruation coitus is generally not pregnant, due to menstruation follicles in the ovaries in the early follicular stage, no mature follicle development and discharge, does not have the basic conditions of pregnancy, but menstruation coitus, for the woman’s health is not good, can not be in order to contraceptive choice in the menstruation period coitus, which is an unavailable choice of measures. Due to the large amount of menstrual blood discharged during menstruation, the mouth of the uterus is in an open state, and coitus can lead to the reverse flow of menstrual blood. In addition, external bacteria can also be infected through the vagina, causing endometritis, pelvic inflammatory disease, etc. The reverse flow of menstrual blood will also lead to endometriosis, which is very unfavorable to women’s health. Therefore, it is recommended to avoid intercourse during menstruation, you can choose the safe period contraceptive method or other contraceptive methods, but the premise of safe period contraception is to be able to accurately predict the ovulation period, but there is a certain failure rate, there is no 100% effective contraceptive measures, and can only be based on the patient’s specific situation to choose the appropriate contraceptive measures.