There are more reasons for high school students to have irregular menstruation, and most of them are considered to be caused by the immaturity of the gonadal axis, hormone level disorders, and so on. 1. Immature gonadal axis: Generally speaking, normal menstruation is regular and self-limiting, and there is a certain relationship between menstruation and estrogen and progesterone in the body. Girls in high school are still in the developmental stage, and the hypothalamus-pituitary-ovarian axis in the body is still immature, which can easily lead to irregular menstruation. 2. Hormone level disorders: at the same time, high school students learning pressure is relatively large, psychological changes are also relatively large, so it is easier to mental stress, irregular diet, but also easy to lead to hormone level disorders, easy to appear menstrual disorders. High school students may also have other reasons for irregular periods, first of all, we need to clarify the causes, to regulate the menstrual cycle, it is recommended to go to the hospital in a timely manner to improve the relevant examinations, standardized treatment under the guidance of a professional doctor.