It is not normal for your period to be early all the time. Normal menstruation has its own regularity, in terms of the menstrual cycle, which is the interval between the first day of two periods, the normal range is around 28 days, and a week of delay or advance before and after is in the normal range. In other words, 21-35 days are within the normal range, and the change of menstrual cycle should be less than 7 days in a year. If the menstrual cycle is less than 21 days, it is called frequent menstruation. Frequent menstruation can easily lead to chronic anemia, vaginitis, and even pelvic inflammatory disease. If organic lesions of the endometrium can be excluded, medication can be considered. The first one, oral short-acting contraceptive pills, regulates menstruation and prevents endometrial pathology. The second one, progestin post-half cycle therapy.