INSIGHTS INTO HYPOTHALAMIC-PITUITARY DYSFUNCTION IN POLYCYSTIC-OVARY-SYNDROME

Citation
Je. Hall et al., INSIGHTS INTO HYPOTHALAMIC-PITUITARY DYSFUNCTION IN POLYCYSTIC-OVARY-SYNDROME, Journal of endocrinological investigation, 21(9), 1998, pp. 602-611
Citations number
66
Categorie Soggetti
Endocrynology & Metabolism
ISSN journal
03914097
Volume
21
Issue
9
Year of publication
1998
Pages
602 - 611
Database
ISI
SICI code
0391-4097(1998)21:9<602:IIHDIP>2.0.ZU;2-P
Abstract
Polycystic ovary syndrome (PCOS) is characterized by menstrual dysfunc tion and hyperandrogenism in the absence of other known causes. While the pathogenesis of PCOS remains elusive and is likely to involve abno rmalities in several systems, there has long been an association of ab normal gonadotropin secretion with this disorder. In recent studies we have determined that 94% of women meeting the broad criteria for PCOS have an increased LH/FSH ratio. Several lines of evidence suggest tha t the mechanisms underlying the increased LH/FSH ratio in PCOS include an increased frequency of GnRH secretion. Decreased sensitivity to pr ogesterone negative feedback on the GnRH pulse generator may play a ro le in this neuroendocrine defect. Additional factors which may contrib ute to the low to normal FSH levels in the face of increased LH includ e chronic mild estrogen increases and possibly inhibin. In addition to these effects on the differential control of FSH, there is increased pituitary sensitivity of LH secretion to GnRH. Both estrogen and andro gens have been proposed as candidates mediating these effects. Superim posed on these underlying abnormalities in gonadotropin secretion is a marked inhibitory effect of obesity on LH secretion which may be medi ated at either a pituitary or hypothalamic level. (J. Endocrinol. Inve st. 21: 602-611, 1998) (C) 1998, Editrice Kurtis.