GONADOTROPIN-RELEASING HORMONE-DEPENDENT CHORIONIC-GONADOTROPIN SECRETION IN A MENOPAUSAL WOMAN

We report the evaluation of a 46-yr-old asymptomatic menopausal woman whose serum hCG concentrations remained persistently supranormal for 3 yr (mean +/- SD, 20 +/- 10 IU/L; n = 19). Holo-hCG and beta-core frag ments were detected in the patient's urine by Ultragel chromatography, followed by specific RIAs. Trophoblastic, germ cell, and other malign ancies appeared to be excluded by the absence of serum tumor markers a nd imaging procedures of the pelvis, abdomen, breast, and chest. Admin istration of a single bolus dose of synthetic GnRH (100 mu g) increase d the serum hCG concentration by 50% (from 26 to 40 IU/L). Administrat ion of the Nal-Glu GnRH antagonist (5 mg, sc, every 12 h for 1 week) d ecreased the serum hCG concentration from 27 to 4.6 IU/ L. The pronoun ced decrease in the serum hCG concentration during antagonism of the a ction of endogenous GnRH by administration of Nal-Glu GnRH suggests th at the pituitary is the source of the supranormal serum hCG concentrat ions, because the pituitary is exposed to the highest concentration of endogenous GnRH.