Birth control pills can delay menstruation. If the patient wants to delay her period, in this case, she can keep taking the pill without stopping, and after taking one box, she can continue to take the next box, which will cause a delay in her period. If the patient is taking the pill routinely for contraceptive purposes only, but there is a delay in menstruation, further blood tests for HCG are needed to rule out pregnancy-induced delay in menstruation. Although the pill is used for contraceptive purposes, it is not possible to achieve 100% contraception. During the use of the pill, patients should pay attention to the monitoring of liver function, kidney function and blood lipids, and drink more water and be more active to prevent blood clots during the use of the pill.