The exact duration of delayed menstruation after taking levonorgestrel tablets varies from person to person. If a woman is a week overdue for her menstruation, she may be pregnant and a pregnancy test should be performed. Levonorgestrel tablets are emergency contraceptives, which are highly effective progestins that cause abnormal thickening of the endometrium and prevent fertilization to form a fertilized egg. If used correctly, the pregnancy rate is only 4%, so there is still a possibility of pregnancy even if the emergency contraceptive pill is taken within 72 hours. Therefore, if you have not had your period for more than a week, an early pregnancy test is recommended. Usually, withdrawal bleeding will occur after stopping the pill, and it usually clears up on its own in about 5 days, but if it lasts more than 7 days, you should go to the hospital for examination. In addition, the emergency contraceptive pill is not recommended for long-term use and is more harmful to women. If you are not planning to have a pregnancy, it is better to take condoms or oral short-acting contraceptives, which are relatively safe.