Women are on the emergency contraceptive pill, which can affect menstruation for 1-2 months and may cause a woman to have a delayed or early period. If a woman is taking a long-acting pill or a short-acting pill on a daily basis, it can affect her menstrual cycle for 3 to 6 months. This is because the pill contains a lot of hormones that inhibit ovulation and can alter the thickness of the endometrium, causing menstrual disorders. Therefore, women who need to take birth control pills should choose them under the guidance of a doctor according to the purpose of taking them, and should not take them blindly, otherwise excessive use of birth control pills may lead to low ovarian function, and excessive premature ovarian failure may lead to permanent amenorrhea, thus affecting women’s health and reproductive function.