The most common and effective emergency contraceptive pill nowadays is Yutin, which is suitable for contraception within 72 hours of sexual intercourse, and it doesn’t work if you take this pill more than 72 hours later. Because this pill is a highly effective progestin to prevent the fertilized egg from being laid, it can also make the cervical mucus sticky so that sperm cannot easily pass through the cervix and enter the uterine cavity. It can also make the endometrium thinner, which is not conducive to the fertilized egg’s implantation. So taking this drug will cause withdrawal bleeding 3-7 days after stopping the pill, and the contraceptive success rate is very high if the bleeding is close to the amount of menstruation. But the contraceptive success rate of the emergency contraceptive pill can reach 90%, so when it’s time for menstruation if it doesn’t come, you should also go to the hospital as soon as possible to have a checkup to avoid an unplanned pregnancy.