title: Plasma luteinizing hormone-releasing hormone levels in normal women and patients with amenorrhea.
abstract: Plasma levels of immunoreactive luteinizing hormone-releasing hormone (LH-RH) in 89 women with normal menstrual cycles and 109 patients with amenorrhea of various etiologies were determined by specific radioimmunoassay after methanol extraction. The LH-RH levels in patients with hypergonadotropism and Sheehan's syndrome were more than 10 pg/ml, and were significantly higher than basal levels during normal cycles (4.2 +/- 0.3 pg/ml). The mean levels of LH-RH were low in all hypogonadotropic patients with amenorrhea, with the exception of a few patients who showed high LH-RH levels suggestive of a pituitary lesion. The LH-RH levels in patients with polycystic ovary syndrome were comparable with basal levels during normal cycles. It is concluded that, although there is considerable overlap of the plasma LH-RH levels in each group of amenorrheic patients divided according to gonadotropin level, determination of LH-RH levels may be useful for the differentiation of hypothalamic amenorrhea from pituitary amenorrhea.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000568:Amenorrhea / Q000503:physiopathology*; D002369:Castration; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000097:blood* / Q000276:immunology; D006801:Humans; D007006:Hypogonadism / Q000503:physiopathology; D007018:Hypopituitarism / Q000503:physiopathology; D008593:Menopause; D008598:Menstruation; D008875:Middle Aged; D011085:Polycystic Ovary Syndrome / Q000503:physiopathology; D014424:Turner Syndrome / Q000503:physiopathology
chemical_list: D007987:Gonadotropin-Releasing Hormone