Clomiphene citrate has been a highly used drug in ovarian stimulation. Although its use as a follicle-stimulant has been largely displaced by safer medication for the patient, it is still used today in treatments to induce ovulation. Therefore, the effects of clomiphene citrate are as follows:
- Follicle-stimulating action
- clomiphene citrate is a drug with the same structure as estrogen, which makes it compete with this female hormone to bind to estrogen receptors in the hypothalamus. Blocking the action of estradiol by clomiphene citrate causes the hypothalamus to increase levels of gonadotropin-releasing hormone (GnRH). All this promotes an increase in the gonadotropins LH and FSH, especially the latter hormone. When estradiol is found to be blocked by the drug, it cannot perform its regulatory function by inhibiting the hypothalamus, and therefore GnRH continues to be secreted. This action causes high levels of FSH to promote the stimulation of follicles in the female ovary. Therefore, its use has been very frequent in assisted reproduction treatments. Its follicle-stimulating action makes it a drug with a high risk of multiple pregnancies.
- Ovulation inducer
- When clomiphene citrate treatment is suppressed, the estrogen receptors in the hypothalamus are released, and estradiol can finally bind to them. As a result, it exerts its inhibitory function in the hypothalamus, and GnRH levels begin to drop, and so do LH and FSH levels.
This happens until the body's estrogen generates a new wave that sets the hypothalamus-pituitary-ovarian axis in motion again and increases the concentration of FSH and LH that will produce ovulation. Ovulation is generated 16-17 days after the use of this medication and is highly used for the treatment of anovulatory or polycystic ovarian syndrome people who have problems to ovulate spontaneously monthly.