The contraceptive mechanism of yutin is to inhibit ovulation, change the thickness of the endometrium, prevent the fertilized egg from being laid, and play a contraceptive role. After taking Yutin, due to the inhibition of ovulation, may cause endocrine disruption, so that the menstrual cycle changes. Some people take yutin, menstruation may be early, and some people have pushed back menstruation, caused by the side effects of yutin. Clinically, if it is only 1 month of early menstruation, there is no need to intervene and give other treatments. If, after taking Yutin, menstruation is often early and more than 5 days early, clinical treatment is needed accordingly, you can take oral Chinese medicine to regulate menstruation, such as taking menstrual regulating Yi Ling tablets.