Serum inhibin B during controlled ovarian hyperstimulation: an additional criterion for deciding whether to proceed with egg retrieval.

OBJECTIVE: To determine the predictive value of the inhibin B increment during controlled ovarian hyperstimulation (COH) for differentiating between poor and normal responders and for deciding whether to continue or stop an IVF attempt. DESIGN: Prospective study. SETTING: Assisted reproduction unit at a university hospital. PATIENT(S): A total of 110 women undergoing IVF for idiopathic, tubal, and/or male infertility. INTERVENTION(S): Blood samples were collected on days 6 and 8 of COH. Inhibin B and E(2) assays were performed. MAIN OUTCOMES MEASURE(S): The degree of inhibin B increment was defined as Delta IB = day-8 value minus day-6 value. We analyzed the correlation of day-6 and day-8 inhibin B values and Delta IB with the number of oocytes retrieved. The predictive value of each parameter was determined by using the receiving operator characteristics curve analysis. RESULT(S): The Delta IB correlated best with the number of oocytes retrieved (r = 0.5) and with the number of embryos obtained (r = 0.26), independently of age. From the receiving operator characteristics curve analysis, a Delta IB cutoff value of 300 pg/mL discriminated poor (few than four oocytes retrieved, n = 16) from normal (more than four oocytes retrieved, n = 94) responders, with a sensitivity of 70% and a specificity of 94%. CONCLUSION(S): The degree of inhibin B increment during COH provides additional information for predicting ovarian response to COH. An increment >300 pg/mL is required to rule out the eventuality of a poor ovarian response.