Impact of Varicocele on Reproductive Hormones in Men: A Systematic Review and Meta-Analysis

The impact of varicocele on testicular function remains debated. This systematic review and meta-analysis evaluated its effects on reproductive hormones, testicular volume, and semen parameters.

A comprehensive search was conducted in PubMed and Scopus for studies published up to January 2025, following the PECO model: Population-adult men; Exposure-varicocele; Comparator-men without varicocele; Outcomes-reproductive hormone levels, testicular volume, and semen quality.

Of 1,622 records, 32 studies met the inclusion criteria. Men with varicocele had significantly higher follicle-stimulating hormone (FSH) (mean difference [MD] 2.18 IU/L, 95% confidence interval [CI] 1.37-2.99, p<0.001) and luteinizing hormone (LH) levels (MD 0.63 IU/L, 95% CI 0.08-1.17, p=0.02), and significantly lower total testosterone (MD -0.71 ng/mL, 95% CI -1.20 to -0.23, p=0.004). No significant differences were observed in free testosterone, prolactin, or estradiol levels between men with and without varicocele. However, testicular volume was significantly reduced in the varicocele group-both on the right (MD -1.40 mL, 95% CI -2.69 to -0.12, p=0.03) and left side (MD -2.97 mL, 95% CI -4.03 to -1.91, p<0.001). Men with varicocele also had significantly lower sperm concentration (MD -34.72 ×10⁶/mL, 95% CI -48.41 to -21.03, p<0.001), motility (MD -20.62%, 95% CI -29.69 to -11.55, p<0.001), vitality (MD -14.75%, 95% CI -24.60 to -4.90, p=0.003), and normal morphology (MD -10.15%, 95% CI -16.53 to -3.78, p=0.002).

Varicocele is associated with elevated FSH and LH levels, alongside reductions in total testosterone, testicular volume, and semen quality. These findings indicate a detrimental effect on both spermatogenesis and Leydig cell function. Clinicians should consider these hormonal and functional impairments when evaluating and managing infertile men with varicocele.