Hypothesis: aberrant puberty and the Stein-Leventhal syndrome.
We hypothesize that the Stein-Leventhal syndrome (type 1 polycystic ovarian disease: SLS-PCOD-I) results from an aberrant puberty. Abnormal neural development in the brain decreases the hypophyseal set-point for negative and positive ovarian hormone feedback. This generates a condition whereby hypophyseal luteinizing hormone (LH) secretion is inappropriately elevated compared to hypophyseal follicle-stimulating hormone (FSH) secretion and is thus termed inappropriate gonadotropin secretion (IGS). The events which create an initial state of IGS are referred to as the "generator" stage. IGS is maintained by ovarian-derived hyperandrogenemia and increased peripheral aromatization of androgens yielding elevated free serum estrone (E1) and unbound estradiol (E2) levels. E1 suppresses release of hypophyseal FSH while E2 exerts positive feedback on LH pulsatile release by increasing pituitary sensitivity to gonadotropin-releasing hormone (GnRH). Diminished circulating FSH levels decrease granulosa cell aromatase activity sufficiently to cause suboptimal ovarian conversion of LH-induced thecal androgens into estrogens. Consequently, chronic local ovarian hyperandrogenemia with associated arrested follicle maturation results in chronic anovulation. Furthermore, an elevated circulating LH/FSH ratio stimulates early development and proliferation of immature follicles causing the appearance of polyfollicular ovaries. In this effector stage of PCOD-I, a vicious cycle is fashioned wherein IGS causes polyfollicular ovaries and increased ovarian androgen production which, in turn, promotes IGS. We suggest that the etiology of this disease involves an aberrant puberty that establishes a persistent faulty hypothalamic-hypophyseal-ovarian axis.
D005260:Female; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology*; D010053:Ovary / Q000503:physiopathology*; D011085:Polycystic Ovary Syndrome / Q000209:etiology* / Q000503:physiopathology; D011627:Puberty