Changes in mRNA expression of insulin-like growth factors and insulin-like growth factor-binding proteins in ovarian granulosa cells after cotreatment with growth hormone in low responders.

BACKGROUND

Insulin-like growth factors (IGFs) in the intraovarian autocrine control mechanism may serve as a central signal, and the granulosa cell is their site of production, reception, and action. In addition, various IGF-binding proteins (IGFBPs) are thought to modulate and regulate the actions of IGFs and in turn influence the growth and maturation of ovarian follicles.

METHODS

To further investigate the follicular growth and maturation regulated by IGFs and IGFBPs in the ovary of low responders, 14 cases of low responders cotreated with growth hormone (GH) were studied. Another 14 normal responders without GH treatment were also recruited as controls.

RESULTS

Serum levels of estradiol on day 6 and day 9 of the cycle and on the day of HCG administration, and the numbers of oocytes retrieved and follicles on the day of oocyte retrieval were significantly lower in low responders before growth hormone (GH) treatment than those in low responders after GH treatment as well as those in normal responders. Expression of both IGF-II and IGFBP-1 mRNA was elevated (by 23% and 35%, respectively) in granulosa cells from low responders after GH treatment as compared to that in low responders before GH treatment. In contrast, there was a substantial decrease (16%) in expression of IGFBP-3 mRNA in granulosa cells from low responders after GH treatment. Clinically, the pregnancy rate was lower in low responders after GH treatment as compared to controls (7% vs. 29%).

CONCLUSION

Cotreatment with growth hormone in low responders might not increase the pregnancy rate.