Generally, if you have unprotected sex, you can take the emergency contraceptive pill after intercourse to prevent pregnancy. The pill is effective up to 72 hours after sex, but the earlier you take it, the better it is. Also, the emergency contraceptive pill is only effective for sex before taking the pill, if you have unprotected sex again after taking the pill, it has no contraceptive effect. The emergency contraceptive pill is only an emergency remedy after sex, it can never be used as a regular contraceptive method, this drug is hormonal, will affect the body’s hormone levels, with more will lead to abnormal menstruation.