Long term therapy with luteinizing hormone-releasing hormone in isolated gonadotropin deficiency: failure of therapeutic response.

We have evaluated the therapeutic response to exogenous LRH (1 mg, sc, either twice daily or three times daily) in six subjects with isolated gonadotropin deficiency. Four males were treated for 6 months, of whom two showed a transient rise in serum testosterone. However, testosterone levels subsequently remained at pretreatment levels in each of the four subjects during LRH therapy. One of the two female subjects displayed a transient rise in 17 beta-estradiol levels. All four males showed a notable rise in testosterone after hCG, and the one female tested responded to menotropins, while receiving LRH. We propose that the number of quanta of gonadotropins released per day with our therapeutic regimen was inadequate to generate a normal gonadal response.