Contraceptive pills are categorized into emergency contraceptive pills, short-acting contraceptive pills and long-acting contraceptive pills. Different contraceptive pills have different mechanisms of action and different usage. Emergency contraceptive pills are generally used after unprotected sex or as a remedy for contraceptive failure, and need to be taken within 72 hours of the event, and the earlier the pill is taken, the more effective it is. Short-acting contraceptive pills are generally 21 days and 28 days, usually from the first day of menstruation to take a fixed time point every day to take a better effect, if the leakage occurs, you need to make up for the fastest time. Long-acting contraceptive pills can be taken once for one month, and the success rate of the first dose reaches more than 98%, which is counted from the day of menstruation, and taken once on the 5th day and once on the 25th day, one tablet each time, and then taken every month according to the time of the second dose.