Dysfunctional uterine bleeding is a common female reproductive endocrine disease. Dysfunctional uterine bleeding, hereinafter referred to as uterine bleeding, is abnormal uterine bleeding caused by dysfunction of the reproductive endocrine axis, which is classified into two major categories: anovulatory and ovulatory, and the causes of different categories vary. Normal menstruation is regulated by the hypothalamic-pituitary-ovarian axis, i.e. the reproductive endocrine axis, and the menstrual cycle, duration, and bleeding volume show obvious regularity and self-limitation. Menstrual cycle, duration and bleeding volume are apparently regular and self-limited. When the reproductive endocrine axis is dysfunctional due to various reasons, dysmenorrhea can occur. Common factors include stress, malnutrition, metabolic disorders, chronic diseases, sudden environmental and climatic changes, dietary disorders, excessive exercise, alcoholism and other drugs. Anovulatory dysmenorrhea is the most common type of dysmenorrhea, accounting for about 80%-90% of dysmenorrhea, which occurs during puberty and menopausal transition, and can also be seen in women of childbearing age. Due to the undeveloped reproductive endocrine axis in puberty, menstrual dysfunction is more likely to be affected by the above factors; the ovary secretes sex hormones, which is an indispensable organ to maintain ovulation and normal menstruation, and menopausal transition period women begin to decline in ovarian function, thus menstrual dysfunction occurs; anovulatory dysfunctional hemorrhage in women of childbearing age is relatively rare, and it is more likely to be due to the influence of internal and external environmental factors, and it may be caused by obesity, polyposis, or other factors, and may also be due to the influence of drugs. Some patients may also have persistent anovulatory dysfunction due to obesity and polycystic ovary syndrome. Ovulatory dysfunctional blood is less common, mostly seen in women of childbearing age, and the cause is unknown in some patients, and some patients are caused by luteal insufficiency or atrophy of the corpus luteum. To summarize, dysfunctional uterine bleeding is mostly caused by endocrine dysfunction due to the influence of internal and external environmental factors.