For whether there is any effect of taking contraceptive drugs before having intercourse, if the oral short-acting contraceptive pill has been taken for more than 7 days, the contraceptive effect may reach 99%. However, if oral emergency contraceptive drugs, there is no way to play a contraceptive role at this time, because emergency contraceptive drugs can only be taken orally within 72 hours afterwards for prevention, the principle is to inhibit the entry of sperm, so that the cervical canal mucus thickens, preventing sperm from entering, so as to achieve the purpose of contraception, if taken orally beforehand, will not play a very good contraceptive effect. If contraception is needed, it is necessary to take it orally within 72 hours afterwards. When taking emergency contraceptive pills orally, you must choose to take them only on an empty stomach or 2 hours after a meal to avoid reducing the effect of emergency contraceptive pills.