[Evidence of follicle responsiveness to FSH by antimüllerian hormone in ovulating women].

Purpose: to test the hypothesis that the anti-müllerian hormone (AMH) serum level reflects the antral follicles' response to the administration of FSH.

Methods: prospective study, including 116 normo-ovulatory infertile patients submitted to controlled ovarian hyperstimulation with GnRH and FSH agonists. The AMH serum level was measured after reaching the pituitary suppression and before the FSH administration (basal day). The number of antral follicles was determined by ultrasonography at the basal day (precocious antral follicles; 2 to 8 mm) and at the day of hCG administration (dhCG; pre-ovulatory follicles; >16 mm). The follicle response to FSH was determined by the percentage of precocious antral follicles which reached pre-ovulatory stage in response to FSH (maturation rate). The correlation of AMH with the patients' age, the total number of precocious antral and pre-ovulatory follicles, collected oocytes, total dose of FHS in the controlled ovarian stimulation and the rate of follicular maturation was studied. For the statistical analysis, it simple regression analysis and the Spearman's test were used, at a 5% significance level.

Results: The serum level of AMH was positively correlated with the number of precocious antral follicles at the basal day (r=0.64; p<0.0001) and pre-ovulatory follicles in dhCG (r=0.23; p=0.01). Exceptionally, the serum level of AMH was negatively correlated with the maturation ratio (r=-0.24; p<0.008).

Conclusions: AMH attenuates the follicular development caused by FSH administration.