Predicting ovarian response to stimulation constitutes a pivotal task in the organization of a successful in-vitro fertilization (NF) programme. The purpose of the current study was to determine whether a new ovarian reserve test, the exogenous follicle stimulating hormone ovarian reserve test (EFORT), could improve the predictive value of the classical follicle stimulating hormone (FSH) measurements on cycle day 3 of ovarian stimulation regarding results of IVF. In this prospective study, 52 IVF candidates aged 27-42 years underwent 52 consecutive IVF cycles. These women received 300 IU of purified FSH i.m. on cycle day 3. Blood samples were taken just before the injection to measure plasma FSH and oestradiol; 24 h later, plasma oestradiol concentration was determined. Two menstrual cycles later, ovarian stimulation was performed for IVF using a time-release gonadotrophin-releasing hormone agonist (GnRHa) and human menopausal gonadotrophin (HMG). For the interpretation of the EFORT results, we considered the post-FSH plasma oestradiol increment (Delta E(2)) and the baseline plasma FSH values (bFSH). The results of these two parameters were compared with the subsequent quality of the ovarian response to stimulation for IVF and the pregnancy outcome. Our results indicated a statistically significant improvement of the predictive value of the bFSH on the ovarian stimulation outcome when the EFORT parameters (bFSH and Delta E(2)) were analysed synergistically. Indeed, 90% of the women whose EFORT parameters were considered to be normal (bFSH less than or equal to 11 mIU/ml, conversion factor to SI units, 1.00; and Delta E(2) greater than or equal to 30 pg/ml, conversion factor to SI units, 3.671) had adequate responses to ovarian stimulation, and 81% of women in whom both parameters were considered to be altered (bFSH greater than or equal to 11 mIU/ml and Delta E(2) < 30 pg/ml) had poor responses to ovarian stimulation. The predictive value of bFSH alone was significantly poorer: only 60% of women having bFSH less than or equal to 11 mIU/ml had adequate responses to ovarian stimulation, and only 45% of women having bFSH > 11 mIU/ml had poor responses to ovarian stimulation (P < 0.02). We concluded that the EFORT is a simple and effective method for screening 'good' and 'poor' responders in TVF, and that the addition of a dynamic component (Delta E(2)) to the classical bFSH measurements has allowed an improvement of the predictive value of this test.
