Non-response to ovarian stimulation in normogonadotrophic, normogonadal women: a clinical sign of impending onset of ovarian failure pre-empting the rise in basal follicle stimulating hormone levels.

The most important aspect of diminished ovarian reserve is the associated decline in reproductive potential. Assessment of ovarian reserve is mainly based on measurement of early follicular phase follicle stimulating hormone (FSH) concentration. The objective of this study was to report the identification of a group of 12 infertile women initially diagnosed as having unexplained or anovulatory infertility, who had a normal baseline hormonal profile and did not respond to repeated ovarian stimulation with gonadotrophins. All developed ovarian failure within a relatively short time span. Non-response to ovarian stimulation was defined by failure to achieve development of follicles >12 mm and failure to raise oestradiol concentration >350 pmol/l in two successive cycles of human menopausal gonadotrophin (HMG) doses of up to five ampoules per day for 5-8 days. Within a mean of 9 months following the failed attempts of ovarian stimulation the mean day 3 FSH concentrations rose from 5.4 +/- 2.7 IU/l to 53.5 +/- 19.7 IU/l. In these patients, day 3 FSH concentration failed to indicate the low ovarian reserve manifested only by lack of clinical response to treatment with gonadotrophins which was the first sign of impending ovarian failure. We conclude that women with normal early follicular phase serum FSH concentrations who do not respond to ovarian stimulation by HMG are at risk of developing ovarian failure within several months.