The 72-hour emergency contraceptive pill only regulates sex up to 72 hours before taking the pill; it has no contraceptive effect on sex after taking the pill. The emergency contraceptive pill is only an emergency contraceptive measure after unprotected sex and is definitely not a regular application method. If you have intercourse after taking the emergency contraceptive pill, you need to continue to take contraceptive measures, and it is recommended to wear condoms throughout to minimize the probability of unintended pregnancy. In addition, the emergency contraceptive pill is less effective than other regular contraceptive methods, so there is a possibility of contraceptive failure. Therefore, if you have a delayed period after taking the emergency contraceptive pill, it is important to have a timely check to see if there is a possibility of pregnancy.