The effect of bromocriptine in the polycystic ovary syndrome.

The effect of chronic administration of bromocriptine to 20 patients with the polycystic ovary syndrome (PCOS) was studied. All patients had normal serum prolactin levels. Bromocriptine 7.5 mg daily was administered for up to 1 year and the biochemical and clinical responses assessed at 3-monthly intervals. Over a period of 3 to 12 months significant reductions in serum LH levels, LH/FSH ratios and in plasma testosterone were observed. In 14 patients, blunting of the previously enhanced LH response to LHRH was observed. Clinical improvement also occurred, most notably in menstrual function. In 12 out of 20 patients a monthly cycle was established and in a further three there was an increase in the frequency of menstruation towards normal. Eleven out of 20 patients ultimately noted a subjective improvement in hirsutism. We conclude that bromocriptine, given to patients with polycystic ovarian disease, inhibits LH hypersecretion, leading to restoration of cyclic ovarian function and reduced androgen synthesis.