Received November 11, 2015
Accepted January 26, 2016

Objective: The aim of this study is to analyze published evidence for the effectiveness of aromatase inhibitor therapy on improving spermatogenesis in infertile men. Methods: A systematic review of randomized controlled trials was performed. The date of the most recent search was October 4, 2015. Two authors independently selected relevant clinical trials, assessed their methodological quality and extracted data. Results: Three studies were included in this review with a total of 100 participants; however we were able to include data from only 54 participants in the analysis. In the representation of meta-analysis with a single study comparing testolactone versus placebo related to the hormone concentrations, there was a statistically significance difference favouring the use of testolactone for Luteinizing Hormone (LH); Estrogen (E2); free Testosterone (free T); free Estrogen (free E2); 17-Hydroxyprogesterone (17OHP); prolactin (PRL). In other analysis with a single study comparing letrozole versus anastrozole, there was also a statistically significance difference favoring the use of letrozole for the increase in both the sperm count and LH. Conclusions: There is only low quality evidence regarding the effectiveness of aromatase inhibitor therapy in infertile men. Further trials are needed with standardized interventions and outcomes.