This is because the emergency contraceptive pill contains large doses of progestin, which can make the cervical mucus sticky and prevent sperm from entering the uterine cavity, and can also change the secretion of hormone levels in women’s bodies, thus preventing or delaying ovulation. So you can take the emergency contraceptive pill within 72 hours after intercourse, if it takes longer after intercourse, there is a drug that is taken within 120 hours, for mifepristone, the mechanism of contraception and yuting the same.