Yutin is an emergency contraceptive pill that may cause delayed menstruation. If menstruation has been delayed for more than a week and has not yet come, and during the period of emergency contraceptive pills, first of all, to rule out the accidental pregnancy, generally more than 12 days after the last intercourse can be measured with a test strip. If you completely exclude pregnancy, menstruation delayed more than a week has not come, it is likely that the emergency contraceptive pills affect the endocrine, delay ovulation and lead to menstruation does not come or delayed. In this case, it is because the dose of progesterone contained in Yutin is particularly high, resulting in delayed ovulation, or even the absence of ovulation. Usually need to come to the hospital ultrasound to see the thickness of the uterine lining, if necessary, take progesterone to promote menstruation, or wait for the emergency contraceptive pills in the body metabolism, can slowly restore the original menstrual cycle. Generally this time will take about 1 month, or even longer, 3-6 months of cases also.