Prolactin pulsatility in patients with gonadal dysfunction.

Abstract

Serum prolactin concentrations have been measured at 15 min intervals for 2 h on 240 occasions in 227 patients with symptoms which could have been due to hyperprolactinaemic gonadal dysfunction. Of the 227, 138 had at least one elevated random prolactin level. Overall, 22% showed no significant fluctuation in prolactin. In 38% the levels fell progressively from the start of the sampling period, this pattern being found most commonly in patients complaining of infertility. The sampling method yielded a basal or unstressed prolactin concentration which was, on average, 27% lower than random prolactin concentrations. However, a comparison with clinical data, the radiological appearances of the pituitary fossa, and the response to bromocriptine therapy, has shown that there is no predictive information in the multiple sampling results that could not have been obtained from two or three random prolactin levels.