Levonorgestrel tablets are emergency contraceptives, which are taken orally within 72 hours after intercourse without measures. The oral contraceptive effect will reach 80%, the same emergency contraceptive drugs are not 100% contraceptive, there will be a 20% chance of failure, you can buy early pregnancy test about 12 days after intercourse to rule out the chance of pregnancy. Because levonorgestrel tablets are emergency contraceptives, there will be certain side effects after taking them orally, which may cause early or delayed menstruation, disruption of the menstrual cycle, or even abnormal bleeding. Levonorgestrel tablets are not recommended to be taken orally for several times because they have certain side effects that may affect the normal menstrual cycle and affect ovulation, and may even cause endocrine hormone disorders, so try not to take them orally more than three times a year.