There are differences in the timing and method of taking different birth control pills. There are many types of birth control pills, such as emergency contraceptive pills, short-acting contraceptive pills and long-acting contraceptive pills, which can be used to prevent pregnancy. Emergency contraceptive pills need to be taken within 72 hours after sexual intercourse. In case of short-acting pill, it needs to be taken regularly for 21 days starting from the 1st to 3rd day of menstruation to have contraceptive effect. In the case of long-acting contraceptives, they need to be taken regularly starting around the 3rd day of menstruation. Short-acting and long-acting contraceptives can be used for regular contraception, while emergency contraceptives can be used for emergency contraception after sexual intercourse. It is generally recommended that women use short-acting or long-acting contraceptive pills for contraception and take emergency contraceptive pills sparingly, as they can easily cause menstrual irregularities. In addition, women may experience withdrawal bleeding (i.e. vaginal bleeding within 1 week after stopping the pill) after applying the pill, so it is important to keep the vulva clean and hygienic to avoid inflammatory infections.