Varicocele is one of the most common correctable cause of male subfertility. According to recent meta-analyzes of RCTs varicocelectomy, in general, leads to significant improvement in semen quality and thereby male fertility. However, varicocelectomy success rate is 55–70%, it means that 30–40% of infertile men does not experience fertility improvement after varicocelectomy. The aim of our review was to search and analyze literature data on clinical-anamnestic and laboratory-instrumental predictors that positively or negatively affect varicocelectomy efficacy. As a result of analysis, we systematized the studied predictors based on the total points calculated on the basis of number and quality of studies that confirm or reject the studied predictor as a significant, into three levels of evidence: predictors of high, moderate and low evidence levels. Predictors of high level of evidence included: initial semen parameters, sperm DNA fragmentation index, and Doppler ultrasound imaging of testicular vessels. The initial serum level of FSH and testicular volume were included in the group of predictors of moderate evidence level. At the same time, such factors as the male age and his female partner age, varicocele grade and infertility duration entered the group of predictors of low evidence level. In this way, we performed “gradation” of predictors of varicocelectomy efficacy in subfertile men based on the analysis of the evidence level of each predictor

Keywords: varicocele, varicocelectomy, predictor, subfertility, semen parameters