Under normal circumstances, short-acting oral contraceptives begin to have a contraceptive effect on the seventh day of continuous use, depending on individual circumstances. Short-acting oral contraceptive pills are mainly made of estrogen and progestin, which are used to inhibit ovulation and change the environment of the uterus and cervical mucus, thus reducing the penetration of sperm and achieving the purpose of contraception. There are many kinds of short-acting contraceptive pills, such as single photo, double photo, triple photo, etc. All of them need a period of time to take effect after use. Secondly, short-acting oral contraceptive pills can also be used to regulate menstruation, generally after taking them for about 3 weeks, and then stopping them for 3-7 days to get menstruation. It is advisable to take the pill at the same time every day to avoid irregular vaginal bleeding and menstrual disorders.