There is a possibility of pregnancy when you have intercourse for the first time without a condom. The prerequisite for conception is the meeting of the egg and sperm to form a fertilized egg, which is possible if ovulation occurs during the first intercourse. For contraceptive purposes, emergency contraceptive pills can be taken orally within 72 hours of intercourse. Emergency contraceptive pills can prevent or delay ovulation or interfere with fertilization for contraceptive purposes and can be up to 98% effective. Most of the ingredients of emergency contraceptive pills are progestin-only preparations. Because they contain a large amount of progestin, they may cause side effects such as nausea, vomiting and irregular vaginal bleeding after taking them, which may have adverse effects on ovarian function and cannot be used as a regular contraceptive method. For women with regular menstrual cycles, ovulation is relatively fixed, while for women with irregular cycles, ovulation is uncertain. Moreover, ovulation is easily influenced by many factors and can be early or delayed, so the method of safe contraception is not safe either. In order to avoid unplanned pregnancy, patients should take safe and effective contraceptive measures, which is also a manifestation of being responsible for themselves.