The term “vacation” usually refers to menstruation. For 10-year-old girls, menstruation for more than ten days is related to the immaturity of its gonadal axis function, so it is generally considered normal, if the symptoms continue to be unrelieved need to be vigilant about the occurrence of polycystic ovary syndrome, then it is abnormal. 1. The gonadal axis function has not matured: 10-year-old girls whose hypothalamus-pituitary-ovarian axis function has not yet fully developed, so the girl may have irregular ovulation, which leads to a lack of progesterone in the body, the endometrium can not be completely peeled off and the prolongation of menstruation, which is considered normal at this time. 2. Polycystic ovary syndrome: If the girl is combined with acne, hairy, obesity and other manifestations, we should be alert to the occurrence of polycystic ovary syndrome, due to its endocrine dysfunction caused by irregular ovulation or no ovulation, the woman is therefore amenorrhea, low menstrual flow, prolonged menstruation and other manifestations, this time it is not normal. For 10-year-old girls, if menstruation lasts for more than ten days, parents are advised to take their children to the gynecology department of a regular hospital as soon as possible, so as to clarify the cause of the disease and then actively treat it under the guidance of the doctor.