Dynamics of early estradiol production may be associated with outcomes of in vitro fertilization.

This study investigated the effects of total E(2) production during controlled ovarian stimulation (COS) calculated by "modified area under the curve for E(2) (AUC-E(2))" and of the changes in E(2) level during the initial stimulation period calculated as "slope of initial increase in E(2) (Sl-E(2))" on the outcomes of IVF cycles using GnRH antagonist protocols. The findings suggest that the rate of initial increase in E(2) rather than total E(2) production during COS might affect the competence of retrieved oocytes in GnRH antagonist cycles.