Prolactin secretion in polycystic ovary syndrome (PCO): correlation with the steroid pattern.

To evaluate the prevalence of hyperprolactinaemia in PCO patients and its possible correlation with a steroid pattern, we studied prolactin secretion (basal and after TRH stimulation) in 40 women affected by typical PCO. LH, FSH, testosterone, oestradiol, oestrone, DHEA-s and 17-OHP serum levels were also evaluated. Twenty-one patients had prolactin (Prl) values in the normal range both in baseline conditions and after TRH stimulation; 10 patients had normal basal values of Prl but an exaggerated response to TRH stimulation; 9 patients had high Prl basal values and an exaggerated response to TRH. The presence of hyperprolactinaemia was associated with increased serum levels of oestrone (P less than 0.01), DHEA-s (P less than 0.01) and 17-OHP (P less than 0.05). In conclusion, hyperprolactinaemia is as relatively frequent condition which affects almost half the patients suffering from PCO and is probably related to an increase of serum oestrogens, mostly oestrone. Moreover, in patients with PCO and hyperprolactinaemia, the production of some other steroids is also affected.