Both men and women should not have intercourse once a day, because men and women have limited energy, and multiple frequent intercourse will have a great impact on the body. Since women have cyclical menstrual periods every month, it is absolutely forbidden to have intercourse during the menstrual period to avoid pelvic infections or endometriosis. Frequent coitus will change the vaginal flora environment leading to a rise in pH, which can lead to flora imbalance and induce vaginal inflammation, the most common is mycotic vaginitis and bacterial vaginitis, and if the man carries trichomonas at the same time, it will also lead to trichomonas vaginitis in women. Frequent coitus in men may lead to energy loss, easy to cause impotence, premature ejaculation abnormalities, so it is recommended that couples have coitus a week, in 2-3 times is appropriate.