Effects of Carnitine and Coenzyme Q10 on Sperm Quality and Pregnancy Rates in Men with Unexplained Infertility: A Systematic Review and Network Meta-Analysis.
Level 1 - systematic review of randomized trials
Systematic review and network meta-analysis of 16 studies
PubMed 40813743 · doi:10.1007/s43032-025-01958-9
What was done
A systematic review and network meta-analysis searching Cochrane Library, EMBASE, Web of Science, and PubMed to assess the effects of oral carnitine and coenzyme Q10 on sperm quality and pregnancy rate in men with unexplained infertility. Primary evaluated outcomes were semen concentration, progressive sperm motility, morphologically normal sperm rate, and pregnancy rate.
What was found
Based on 16 included studies, L-carnitine, coenzyme Q10, and L-carnitine plus acetyl-L-carnitine significantly improved sperm parameters versus placebo. CoQ10 produced the highest increase in sperm concentration (SMD 2.98 [95% CI: 1.13 to 7.87]), and L-carnitine produced the largest improvement in progressive sperm motility (SMD 4.19 [95% CI: 1.60 to 10.95]). No quantitative data for pregnancy rate or normal morphology were reported in the abstract.
Why it matters
This network meta-analysis differentiates the potential roles of common antioxidants, suggesting CoQ10 primarily benefits sperm count while L-carnitine benefits sperm motility in unexplained male infertility.
Limits
The abstract does not state the total participant count or individual study designs. Quantitative results for pregnancy rates and morphology were omitted from the abstract, and the reported effect estimates show very wide confidence intervals.