O-222 Antral follicle responsiveness to FSH assessed by the Follicular Output RaTe (FORT) predicts IVF-ET outcome

the Low to the High FORT groups (33.3%, 51.2%, and 55.7%, respectively, P < 0.003) as well as embryo implantation rates (23.3%, 34.4%, and 37.7%, respectively, P < 0.003). Conclusions: The present findings indicate that antral follicleresponsiveness to FSH, as far as it is measurable by FORT, is positively related to IVF-ET outcome, thereby placing FORT as a promising qualitative marker of ovarian function. In agreement with our own previous report (Genro et al., in press), FORT constitutes an objective approachto assessing the actual response of folliclesto exogenous FSH, which is not influenced by the size of the preexisting cohort of antral follicles. Further, this innovative index invites us to revise the usual criteria of COH cycle cancellation based on the absolute number of growing follicles.