Yutin is a common daily emergency contraceptive pill that works for up to 72 hours and may cause abnormal vaginal bleeding, which usually occurs about 7 days after the pill. The composition of Yutin is a combination of estrogen and progestin, which can change the level of hormones in the body to prevent the fertilized egg from being laid to achieve the purpose of contraception. After taking Yutin, bleeding can occur 4-5 days or even 1 week after stopping the pill, the amount of bleeding is less than the amount of menstruation, and the duration is shorter and cannot be considered as menstrual flow. This is because a large amount of progestin into the body of women, suddenly stop the endometrium can lose hormonal support, and the occurrence of withdrawal bleeding, when the bleeding volume is large, can be treated as a menstrual period. During the bleeding after taking yutin, patients need to pay attention to hygiene and prohibit intercourse to avoid infection. Yuktin as an emergency contraceptive pill, the side effects are large, can not be taken more than 2 times a month, not more than 3 times a year.