Menstruation is menstruation. Women who have intercourse during menstruation are usually not pregnant, but it is usually not recommended to have intercourse during menstruation, as it can easily cause infections. Women with regular menstrual cycles, the day of ovulation is counted from the first day of the next menstrual period, counting down 14 days to the day of ovulation, 4 days before and 5 days after the day of ovulation to become ovulation, ovulation is easy to fertilization, if this time coitus will increase the probability of conception. During menstruation, the ovaries are in the follicular phase rather than the ovulation phase, which generally does not cause pregnancy. The woman’s body immunity is reduced during menstruation, coitus may occur bacterial infection, induced gynecological inflammation, may also stimulate the uterus contraction of menstrual disorders, serious cases may also cause endometriosis, so it is recommended that women avoid coitus during menstruation. It is recommended that women pay attention to personal hygiene during menstruation, to change sanitary napkins, wash the vulva every day, and avoid taking a shower instead of a tub bath to prevent inflammatory infections. In addition, such as menstruation after coitus discomfort symptoms suggest timely consultation, clear cause of disease follow the doctor’s instructions standardized treatment.