What is the pharmacological effect of emergency contraception?

Emergency contraception is usually taken after unprotected sex, and its function is played after sperm enters the uterine cavity. For example, Mei Dan levonorgestrel enteric-coated tablets, which is a simple progesterone, will not make girls gain weight and acne, and will not affect their menstrual period. By inhibiting ovulation and thickening cervical mucus, fertilized eggs are not easy to form or implant? The medicine has the patent of enteric coating. After taking it, the tablet will not disintegrate until the small intestine, which greatly reduces vomiting and nausea caused by disintegration in the stomach, leaving more ingredients in the body, thus ensuring the dosage of the medicine and greatly improving the success rate of contraception. Through four clinical trials, the success rate is as high as 99.8%. If you want to have contraceptive effect as much as possible, you need to take it within 72 hours after the event, and the sooner you take it, the better.