[Variations of the plasma levels of gonadotrophins (FSH and LH) and of its response to stimulation with gonadotrophin releasing hormone (GnRH) with different plasma levels of prolactin (PRL) in women with the syndrome of galactorrhea-amenorrhea (author's transl)]. / Variaciones de la tasa plasmática de gonadotrofinas (FSH y LH) y de su respuesta al estímulo con hormona liberadora de gonadotrofinas (GnRH) ante distintos niveles plasmáticos de prolactina (PRL) en mujeres con síndrome de galactorrea-amenorrea.

In 15 women with either isolated amenorrhea or amenorrhea associated to galactorrhea the basal levels of PRL allowed a clear differentiation into three groups. The first group (n = 3) had normal PRL levels (x +/- SD, 8.0 +/- 4.8 ng/ml), the second group (n = 4) had moderately elevated PRL (25.6 +/- 6.5 ng/ml), and the third group (n = 8) had very high PRL (176.0 +/- 76.1 ng/ml). All the patients in the third group had a pituitary adenoma. In the three groups the basal levels of FSH and LH and their response to GnRH were measured with the purpose of uncovering possible relationships between these results and the levels of PRL, and the tumoral or non-tumoral origin of the hyperprolactinemia when it was present. No statistically significant differences were found amongst the three groups. The results suggest that hyperprolactinemia has no influence upon gonadotrophin release or the endogenous release of GnRH. The measurement of plasma gonadotrophins and their response to GnRH appears to be of no clinical value for the differential diagnosis of the hyperprolactinemias.