Objective: To evaluate the additional value of a second basal follicle stimulating hormone (FSH) level, in a different cycle, in the prediction of poor response in in vitro fertilization (IVF) by a single basal FSH measurement.
Study design: In 120 patients, basal FSH was determined prospectively in 2 spontaneous cycles. The additional value of a second basal FSH measurement in the prediction of poor ovarian response in IVF by a single basal FSH measurement was studied.
Results: Due to chance variation, the predictive accuracy of a poor response of the first and second basal FSH measurement differed (ROC(AUC) .84 and .74, respectively). In a multivariate analysis, the higher of the first and second basal FSH levels provided the best predictive accuracy (ROC(AUC) .85). In terms of clinical relevance, however, a predictive model with the highest basal FSH level provided only slightly more correct predictions of poor and normal ovarian response than did models based solely on a single basal FSH measurement.
Conclusion: Using basal FSH, a substantial number of patients will be misdiagnosed with regard to their ovarian response potential in IVF, even if repeat measurement is performed.