Does plasma insulin level affect ovarian response to exogenous administration of follicle-stimulating hormone in women without polycystic ovary syndrome?

BACKGROUND: Raised insulin levels have been shown to contribute to ovarian overproduction of androgens. Hyperinsulinemia, usually associated with polycystic ovary syndrome (PCOS), brings about greater ovarian endocrine and morphological responses to ovulation induced by follicle-stimulating hormone (FSH). This indicates that elevated levels of insulin play a role in the endocrine and paracrine control of the ovaries. OBJECTIVE: The aim of the present study was to investigate whether basal insulin levels influence ovarian response to FSH in healthy women (non-PCOS) undergoing assisted reproduction by in vitro fertilization-embryo transfer (IVF-ET). METHODS: The study included 36 consecutive women, 27-45 years old, undergoing IVF-ET for tubal-factor or male-factor infertility. Serum insulin levels were determined on the day of administration of gonadotropin-releasing hormone analog (GnRHa) and on the first day of FSH administration. RESULTS: Mean insulin levels were 6 +/- 3 and 7 +/- 3 microU/ml on the day of GnRHa and FSH administration, respectively. No correlations were found between basal insulin level, days of treatment, total FSH dose, estradiol level and the number of oocytes retrieved. CONCLUSIONS: The results of the present study show that normal levels of insulin do not seem to influence ovarian response to FSH in non-PCOS women. In all patients included in our study, serum insulin levels did not correlate with IVF stimulation data (days of stimulation, total FSH dose) nor with IVF-ET outcome. Thus the study demonstrates that, in patients who are not insulin-resistant, insulin does not correlate with ovarian response to FSH administration.

Anti-Müllerian hormone plasma levels in spontaneous menstrual cycle and during treatment with FSH to induce ovulation.

BACKGROUND: Anti-Müllerian hormone (AMH) is member of the transforming growth factor-beta superfamily of growth factors. AMH is detected in serum from women of reproductive age and its levels vary slightly with the menstrual cycle, reaching the peak value in the late follicular phase. The present study was undertaken to assess the effect of controlled ovarian stimulation on AMH secretion by the ovary in healthy women in order to obtain more insight into the relationship between this peptide and gonadal steroids. METHODS: Twenty-four normally cycling women attending the infertility clinic volunteered for this study and AMH was measured in blood samples obtained during both spontaneous and FSH-treated cycles. RESULTS: AMH plasma levels did not change significantly from day 2 to day 6 in spontaneous cycles. On the contrary, AMH levels decreased progressively from day 2 to day 6 in FSH-treated cycles. A significant positive correlation was found between the decrease in AMH and the increase in estradiol plasma levels in FSH-treated cycles and between basal AMH and the peak estradiol (E2) during exogenous FSH administration. CONCLUSIONS: The present study demonstrated that AMH plasma levels did not change during the follicular phase of the menstrual cycle and that exogenous FSH administration is followed by a significant reduction in AMH levels which is probably secondary to the gonadotrophin effect on the process of follicular development.