Clomiphene Citrate Plus Cabergoline Versus Clomiphene Citrate Alone in Treatment of Polycystic Ovary Syndrome Associated Infertility

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of reproductive aged women and affects approximately 5-12 % of the female population.

In 2003 in Rotterdam , Rotterdam diagnostic criteria were redefined PCOS as affected individuals must have two out of the following three criteria:

1. Oligo- and/or anovulation, (ovulation occurs less than once every 35 days).
2. Hyperandrogenism, clinical signs include hirsutism, acne, alopecia, and frank virilization, while chemical indicators include raised concentrations of total testosterone and androstenedione , and elevated free androgen index.
3. Polycystic ovaries on sonographic examination, presence of 12 or more follicles in either ovary measuring 2-9 mm in diameter, increased ovarian volume more than 10 cm3 and/or increase in stromal echogenicity. Clearly, according to the Rotterdam diagnostic criteria, the majority of women with PCOS can be diagnosed without the need of laboratory examinations.

Clomiphene citrate (CC) is still the first-line medication for the induction of ovulation. It is an anti-estrogenic compound made up of two isomers, enclomiphene and zuclomiphene; the latter being the more potent of the two. It is a non-steroidal compound closely resembling estrogen. CC acts by blocking estrogen receptors, particularly in the hypothalamus, thereby signaling a lack of circulating estrogens and inducing a change in the pulsatile release of gonadotrophin-releasing hormone (GnRH). This induces release of follicle stimulating hormone from the anterior pituitary and is often enough to set the cycle of events leading to ovulation into motion.

Cabergoline, ergot-derived dopamine agonists with a very long half life, is an effective prolactin suppressor. Cabergoline oral administration contains a weekly dose of 0.5 - 3 mg, which could be increased, if needed, to twice a week. This medicine has slight dopamine agonistic side effects, headache being the most common one. Treatment in the very beginning should start with a partial dose (half a pill) at bedtime with a small amount of food. Low incidence of side effects and its weekly dose has made Cabergoline a choice drug for treatment of related diseases.