Birth control pills are effective. There are short-acting, long-acting and emergency contraceptives. The short-acting pill is taken once a day for 21 days. As long as you don’t miss a pill, the success rate is over 90%. Long-acting pills have more side effects and are generally not used nowadays. Emergency contraceptive pills often occur after unprepared intercourse. As long as there is no more than 72 hours, oral is effective, but if you take it within 24 hours of intercourse, its efficacy is higher, can reach more than 90%, more than 24 hours or 48 hours the effect will be reduced. Drugs have certain side effects, it is not recommended to apply for a long time, try to use a condom contraception or placement of intrauterine device.