Cabergoline Influences Ovarian Stimulation in Hyperprolactinemic Patients With Polycystic Ovary Syndrome

Abstract

Women with polycystic ovary syndrome (PCOS) typically have abnormal gonadotropin secretion and, in 30% of cases, mild and transient hyperprolactinemia. Elevated prolactin (PRL) is found in the late follicular and luteal phases of natural as well as stimulated cycles. Increased levels of both PRL and luteinizing hormone (LH) conceivably reflect a reduced dopamine inhibitory effect. To clarify the influence of dopaminergic control in PCOS, the investigators retrospectively examined the effects of cabergoline, a potent dopamine agonist that inhibits PRL secretion, on the ovarian response to stimulation with recombinant follicle-stimulating hormone (FSH). Enrolled in the study were 44 couples in which the women were diagnosed as having PCOS, in part because of anovulatory infertility and/or oligomenorrhea or amenorrhea. Eighteen women (group A) whose mean serum PRL was 32. 8 ng/ml received 0.25 mg of cabergoline (Dostinex) per week before and during ovarian stimulation. The remaining 26 women (group B), with a mean PRL of 31.3 ng/ml, received no treatment for hyperprolactinemia. For ovarian stimulation investigators used Triptorelin, a gonadotropin-releasing hormone agonist; FSH in an individualized dose; and human chorionic gonadotropin (hCG). The two groups were similar demographically and clinically. The total of 107 ovulatory-stimulated cycles available for study represented approximately 2 ½ per participant. Cabergoline reduced the mean serum prolactin to 12.5 ng/ml at the time stimulation began. Women not given cabergoline received significantly less recombinant FSH per cycle and were stimulated for a shorter time before hCG was given. Their peak serum estradiol levels were significantly higher than in group A women. Serum progesterone levels on the day of hCG treatment did not differ significantly in the two groups. Ultrasonography showed that hyperprolactinemic women developed significantly more follicles of all sizes on the day hCG was given than did those given cabergoline. Mild ovarian hyperstimulation syndrome (OHSS) developed in 6.2% of group B women and 2.4% of those in group A; all these cycles were canceled. There were 8 pregnancies in group A, 3 of them multiple, and 11 in group B, 5 of them multiple; the differences were not significant. These findings agree with the existence of a dopaminergic component in the regulation of LH release in women with PCOS. Pretreatment with the dopamine agonist cabergoline seems to reduce the ovarian response to recombinant FSH without altering the pregnancy rate or the risk of multiple pregnancy. This might be a helpful means of limiting the risk of OHSS.