An 8-day early menstrual period is considered abnormal. In clinical practice, the vast majority of women have a menstrual cycle of 28-30 days once. If the cycle is less than 25 days, it is considered clinically abnormal. If the menstruation is 8 days early, it is commonly caused by the following reasons: the first is endocrine disorders, such as staying up late, irregular life, anxiety, emotional changes or environmental changes that cause insufficient luteal function, which can lead to early menstruation. The second is the clinical use of certain drugs, such as emergency contraceptives or short-acting contraceptives, progesterone, which can lead to early menstruation. The third is due to inflammation of the endometrium, submucosal fibroids or endometrial polyps, or endometriosis, which can lead to early menstruation. Therefore, it is recommended to do ultrasound examination, check sex hormone six, thyroid function, blood routine in clinical practice and give certain treatment according to the results.