Emergency contraceptive pills have a lot of side effects and should not be taken more than three times a year and at most once a month. The side effects of the emergency contraceptive pill are as follows: 1. endocrine disorders, the emergency contraceptive pill contains a large amount of progestin, after taking it causes endocrine disorders, irregular vaginal bleeding, taking the emergency contraceptive pill once, usually affects three menstrual cycles. 2. gastrointestinal stimulation, nausea, vomiting and other gastrointestinal symptoms after taking the pill, can be taken before bedtime to reduce adverse reactions. 3. aggravate breast disease, progestin will stimulate the 4, other adverse reactions, such as facial spots, increased leucorrhea, etc. It is best for women to take contraceptive measures that suit them, and not the emergency contraceptive pill as a regular contraceptive method.