Either taking the emergency contraceptive pill during the safe period or at other times can have certain effects on the body. Because the emergency contraceptive pill is a highly effective progestogen, it mainly inhibits ovulation and causes abnormal thickening of the endometrium to achieve the purpose of contraception. Therefore, oral emergency contraceptive pills have certain side effects, which may lead to endocrine disorders and abnormal menstruation, or irregular vaginal bleeding or withdrawal bleeding. In addition, the progestin content of emergency contraceptive pills is five times higher than that of other contraceptive pills, which may affect liver and kidney functions. Therefore, it is recommended not to use the emergency contraceptive pill as a regular contraceptive method, but to use condoms for contraception in daily life.