Significance of serum inhibin B concentration for evaluating improvement in spermatogenesis after varicocelectomy

BACKGROUND: The study aim was to clarify the relationship of serum inhibin B concentrations to recovery of spermatogenic function after varicocelectom y, both as a predictor of improvement in the seminogram and as a means of m onitoring hormonal function after surgery. METHODS: Fifty-two varicocele pa tients, including five with normal sperm concentrations, were studied. Chan ges in the seminogram, serum hormone concentrations and serum inhibin B wer e evaluated in the 47 oligozoospermic patients after surgery. Preoperative inhibin B concentrations correlated significantly with serum concentrations of FSH (r = 0.598, P < 0.0001) and testosterone (r = 0.380, P < 0.02). Inh ibin B concentrations also correlated significantly with sperm concentratio n (r = 0.351, P < 0.02) and total testicular volume (r = 0.578, P < 0.0001) . No significant correlation was seen between inhibin B and the Johnsen sco re. Preoperative concentrations of inhibin B were higher in patients who in creased their sperm concentration after surgery (responders) than in those without improved concentrations (non-responders). No significant difference was observed between pre- and postoperative inhibin B concentrations in re sponders or non-responders. However, 15 of 25 (60%) patients with increased inhibin B showed improvement of the seminogram, while only five of 22 (23% ) patients with no change or a decrease in inhibin B had any improvement (P < 0.05). CONCLUSIONS: Preoperative serum inhibin B concentration could not reliably predict a response to varicocelectomy. However, a change in serum inhibin B concentration after varicocelectomy might be helpful to evaluate the improvement of testicular function after varicocelectomy.