The pathogenesis of anovulatory functional uterine bleeding in adolescence

Most cases of anovulatory functional uterine bleeding in adolescence are caused by the incomplete development of the hypothalamus-pituitary-ovarian axis. Mental stimulation or illness can easily cause dysfunction of the newly developed hypothalamus-pituitary-ovarian axis and cause functional uterine bleeding.

Mechanism of anovulatory functional uterine bleeding

The incomplete development of the hypothalamus-pituitary-ovarian axis leads to the failure of the ovaries to synthesize progesterone. The endometrium proliferates under the action of estrogen alone. When the estrogen level can no longer maintain the thickened endometrium, part of the endometrium sheds and bleeds, which is called breakthrough bleeding. After one part is repaired, another part sheds again, causing continuous bleeding. Due to the lack of progesterone, the broken ends of the spiral arteries of the endometrium do not contract, resulting in heavy bleeding. If there are multiple open bleeding vessels in the endometrial shedding area, the amount of bleeding will increase sharply.

Causes

1. Hyperthyroidism or hypothyroidism during adolescence may be accompanied by functional uterine bleeding. Experiments have found that when the thyroid function is low, the metabolic rate of ovarian cells decreases, the follicles are poorly developed, and the secretion of estrogen is insufficient; when the thyroid function is hyperactive, the secretion of ovarian hormones increases, the menstrual cycle becomes shorter, or ovulation stops, the endometrium proliferates too long, and anovulatory functional uterine bleeding occurs during adolescence.

2. Polycystic ovary syndrome may occur during adolescence and is characterized by anovulation, manifesting as amenorrhea or anovulatory functional uterine bleeding.

3. In adolescents with adrenal hyperplasia, due to increased androgen in the body, ovulation disorders may also cause anovulatory functional uterine bleeding.