ABSTRACT
PURPOSE: We investigated whether oligospermic or asthenospermic men have decreased testosterone-to-estradiol (TE) ratios and whether this condition can be corrected with an oral aromatase inhibitor. We also determined the predictive value of pretreatment TE ratios for aromatase inhibitor efficacy in infertile men. MATERIALS AND METHODS: From June 2002 to December 2003, a total of 68 subfertile men with abnormal TE ratios were treated with 1 mg of anastrozole daily for 3 months. Changes in serum testosterone, serum estradiol, TE ratios, and semen parameters were evaluated 3 months after this therapy. RESULTS: Men treated with anastrozole had an increase in TE ratios (mean 0.2+/-0.7 [SE] versus 0.38+/-0.15; p<0.001). Semen analysis before and during anastrozole treatment showed an increase in sperm concentration (48.96 versus 70.42 million/mL; p<0.001) and motility (26.3 versus 33.2%; p<0.005). CONCLUSIONS: Men who are subfertile with lower TE ratios can be treated with an aromatase inhibitor with an increase in TE ratios that correlates with improved semen characteristics. We advise that an aromatase inhibitor be used in oligospermic or asthenospermic men if the TE ratio is below 0.2.
