Screening by the Clomiphene Citrate Challenge Test Does Not Predict Consecutive IVF Outcome

Abstract

Objective: To validate the Clomiphene citrate (CC) challenge test for the prediction of ovarian sensitivity and clinical outcome during consecutive IVF cycle(s). Design: Prospective study of ninety-three patients undergoing the CC challenge test before scheduled start of IVF treatment from January 1998 to May 1999. Materials and Methods: Parameters of CC challenge test: Follicle stimulating hormone (FSH), Inhibin-B (INHB), number of dominant follicles were related with the sonographic ovarian dynamics during IVF treatment and clinical outcome: total amount of gonadotropins, duration of stimulation, cancellation rate, number of oocytes, number of embryos, pregnancy rate. The CC challenge test as screening test for the prediction of ovarian response during IVF was validated. Spearman’s correlation coefficient was used to establish relations. Median values were compared between groups using the Mann-Whitney test. Multiple linear regression analysis was used to evaluate various parameters of the CC challenge test versus IVF outcome. In order to validate the CC challenge test for prediction of ovarian response during IVF, receiver operating characteristics (ROC) curves were constructed. Results: FSH levels after CC intake correlated significantly with the number of punctured follicles (p<0.01) and number of oocytes obtained (p<0.01). INHB after stimulation showed significant correlation with the number of punctured follicles (p<0.01). Significant negative correlations were found between the number of follicles on the 10th day of the CC challenge test and the follicles on day of aspiration (p<0.01) as well as the number of oocytes obtained (p<0.01). However, it was not possible to find a clinically acceptable cut off level to predict poor response or bad response using these endocrine or sonographic parameters. The receiver operating characteristics curve comparing sensitivity and specitivity in relation to stimulated FSH levels with the number of oocytes, number of mature follicles and number of embryos showed an area under the curve of 0.70, 0.69 and 0.56 respectively. Conclusion: FSH, INHB and the number of follicles during the CC challenge test correlated significantly with ovarian response during the subsequent IVF-cycle. However, no cut off levels of the parameters of the CC challenge test could be found predicting ovarian reserve in the following IVF cycle and demonstrated a poor clinical use.