Emergency contraceptive pills are hormonal pills that can cause changes in the endocrine hormones in the body, leading to early or even delayed menstruation, and may stimulate the endometrium to shed a small amount, causing withdrawal bleeding. At the same time, emergency contraceptive pills may also cause confusion in the intestinal tract, such as diarrhea, and in some cases may cause breast pain, but this condition will slowly ease after the month. In some cases, the oral emergency contraception may cause disruption of the menstrual cycle for 3 months, and observation is recommended. If the menstrual cycle is disordered for more than 3 months, it is recommended to take a blood test for endocrine hormones on an empty stomach on the 2nd-5th day of menstruation to see if there are any abnormalities in endocrine hormones, which can be regulated according to the situation.