Xiao Yun, 18 years old, had her period at the age of 13, but it has not been very regular, often coming once every few months, and has been coming for nearly a year. It is indeed shocking to hear that an 18-year-old girl is menopausal. This is not only unheard of, but also rarely seen clinically, especially if the menopause is due to mental factors. The most common form of menorrhagia in adolescent girls is pubertal amenorrhea, but amenorrhea is not menopause. Amenorrhea is divided into primary amenorrhea and secondary amenorrhea. Girls who do not have menstruation at the age of 18 are called primary amenorrhea, and those who have had menstruation and have stopped menstruating for more than 6 menstrual cycles are considered secondary amenorrhea. Physiological amenorrhea is pre-pubertal, pregnancy, lactation and post-menopause, pathological amenorrhea, primary amenorrhea suggests congenital diseases are more common, and secondary amenorrhea is considered to be an acquired disease. Menopause in teenage girls is mostly congenital dysplasia The so-called menopause implies ovarian atrophy and functional decline. The ovary is the organ that provides eggs, with follicle development and cyclic production of sex hormones. If there are no eggs due to congenital ovarian dysplasia, it is primary ovarian amenorrhea, and if the ovaries are depleted and amenorrheic due to acquired causes, it is secondary ovarian amenorrhea, also known as premature ovarian failure. A woman’s egg reserve is limited during her lifetime, and when the eggs are depleted and menopause occurs, it is called menopause. The average age of menopause in normal women is about 50 years old, and menopause before the age of 40 is called premature ovarian failure, the incidence of which varies widely from region to region, ranging from 0.88% to 14.6%, but menopause in young girls is rare and is mostly due to congenital ovarian insufficiency. The common causes of menopause due to premature ovarian failure include inadequate egg reserve (e.g., partial deletion or chimerism of sex chromosomes leading to early failure due to insufficient number of eggs), early failure due to rapid egg consumption in certain chronic or wasting diseases, environmental factors such as physical, chemical, radiological, viral, alcohol and smoking factors affecting egg consumption, ovarian tumors destroying ovarian tissue or surgical removal of both ovaries, and Immunological factors and genetic mutations. The most important diagnostic indicators are follicle stimulating hormone FSH > 40 IU/L and estradiol E2 < 20-30 pg/dl. Menorrhagia in adolescent girls is mostly stress related. Excluding organic lesions, menstrual irregularities in adolescent girls are mostly related to emotions, stress and some changes in lifestyle habits. Long-term study pressure, depression, sulking or suffering from major mental stimulation and psychological trauma can reduce estrogen secretion, which can lead to menstrual disorders and amenorrhea. In addition, girls who are too thin or obese are also prone to menstrual disorders. Some studies have confirmed that the first menstrual cycle can occur in girls with at least 17% of their body weight in fat and at least 22% of their body weight in fat to maintain a normal menstrual cycle. Excessive dieting or even the development of anorexia nervosa can lead to hypothalamic amenorrhea, which can be very harmful to the overall health of young girls. When amenorrhea and low estrogen manifestations occur, estrogen and progesterone supplementation is needed to help them have a correct understanding of their weight, and menstruation can be restored when they gradually regain their normal weight. Obesity can also cause endocrine disorders such as polycystic ovary syndrome, but this is usually seen in women of childbearing age. If amenorrhea is accompanied by metabolic disorders, fatness, increased body hair, and acne, polycystic ovary syndrome should be considered. For amenorrhea in young girls, it is important to prevent transitional treatment. Generally speaking, the hypothalamic-pituitary-ovarian axis develops 1.5 to 5 years after the girl's menarche. Therefore, girls with irregular menstruation within 5 years of menarche mostly do not need treatment, but if a girl has irregular menstruation to come, come once with more menstrual bleeding, and the period lasts too long, you should go to a gynecological endocrinology specialist for diagnosis to prevent the occurrence of hemorrhagic anemia, which can manifest as dizziness, weakness, panic, shortness of breath and other phenomena, and in serious cases may be life-threatening. Most of the amenorrhea in adolescence is reversible and can usually be cured after a period of treatment and physical and mental adjustment. It should be noted that when low estrogen is present for estrogen supplementation treatment, if the child is too young and height development is not in place, prolonged use of estrogen treatment may cause epiphysis closure and affect the child's height.