Treatment of Amenorrhea
The first step is to establish a cause for the amenorrhea. The progesterone “challenge test” is commonly used to deter-mine whether or not the patient has adequate estrogen, a competent endometrium, and a patent outflow tract. An injection of 100 mg of progesterone in oil or a 5-day to 14-day course of oral medroxyprogesterone acetate or micronized progesterone is expected to induce proges-terone withdrawal bleeding within a few days after com-pleting the oral course. If bleeding does occur, the patient is likely to be anovulatory or oligo-ovulatory. If withdrawal bleeding does not occur, the patient may be hypoestro-genic or have an anatomic condition such as Asherman syndrome or outflow tract obstruction.
Hyperprolactinemia associated with some pituitary adeno-mas (or other medical conditions) results in amenorrhea and galactorrhea (a milky discharge from the breast).Approxi-mately 80% of all pituitary tumors secrete prolactin, causing galactorrhea, and these patients are treated with either cabergoline (Dostinex) or the dopamine agonist bromocriptine (Parlodel). In approximately 5% of patients with hyperprolactinemia and galactorrhea, the underlying etiology is hypothyroidism. A low serum thy-roxine (T4) level eliminates negative feedback signaling to the hypothalamic–pituitary axis. As a result, TRH (thyrotropin-releasing hormone) levels increase. Positive feedback signaling that stimulates dopamine secretion is also absent, causing a decrease in dopamine levels. Elevated TRH stimulates release of prolactin from the pituitary gland. The reduced dopamine secretion results in elevated levels of TSH (thyroid-stimulating hormone) and prolactin.
In patients who desire pregnancy, ovulation can be induced through the use of clomiphene citrate, human menopausal gonadotropins, pulsatile GnRH, or aromatase inhibitors. In patients who are oligo-ovulatory or anovula-tory (polycystic ovary syndrome), ovulation can usually be induced with clomiphene citrate. In patients with hypogo-nadotropic hypogonadism, ovulation can be induced with pulsatile GnRH or human menopausal gonadotropins. Women with genital tract obstruction require surgery to create a vagina or to restore genital tract integrity. Menstruation will never be established if the uterus is absent. Women with premature menopause may require exogenous estrogen therapy.