The effect of the emergency contraceptive pill can last up to six hours after taking it, that is, after taking the emergency contraceptive pill, there is still a contraceptive effect within six hours of intercourse, but more than six hours there is no contraceptive effect. Because the emergency contraceptive pill is generally used for unprotected sex within 72 hours, if you take the pill more than 72 hours later, the earlier the pill is taken, the better the effect. If there is no fertility requirement, it cannot be used as a regular contraceptive measure because this drug can lead to endocrine disruption, menstrual disorders and suppression of ovulation, so taking too much of it can cause irregular vaginal bleeding.