Conventional contraceptives are divided into short-acting contraceptives, long-acting contraceptives and emergency contraceptives, and the time of taking each of them is different and should be analyzed on a case-by-case basis. Short-acting contraceptives are mainly composed of estrogen and progestin, and are usually taken on the 3rd-5th day of menstruation, and need to be taken continuously for a course of 28 days. Long-acting birth control pills are usually taken only once a month, usually starting with one pill on the 5th day of menstruation. Emergency contraceptive pills, whose main ingredient is progestin, work similarly to short-acting pills and are generally effective when taken within 72 hours after sex. There are two types of emergency contraceptive pills, one that can be taken once and another that can be taken 12 hours apart after the first pill. Before taking the pill, it is necessary to make sure that the liver and kidney functions are normal. Second, conventional contraception is generally recommended to use long-acting and short-acting contraceptives, and emergency contraceptives should be taken as little as possible because of the relatively large side effects.