Efficacy and Safety of Coenzyme Q10 in Idiopathic Male Infertility: A Systematic Review and Meta-Analysis of Randomized Trials

Despite numerous studies on coenzyme Q10 (CoQ10) as a treatment for idiopathic male infertility (IMI), clear clinical guidance remains lacking. This systematic review and meta-analysis (SRMA) aimed to evaluate the efficacy of CoQ10 and determine the optimal dose, formulation, and treatment duration compared to placebo or other therapies. We searched PubMed, Science Direct, and Cochrane Library using relevant keywords to identify studies assessing CoQ10's effects on sperm parameters, seminal CoQ10 levels, and clinical pregnancy rates in men with IMI. Study quality was assessed using the Revised Cochrane Risk of Bias tool (RoB2), and meta-analyses were conducted using Review Manager 5.4. The protocol was registered in PROSPERO (CRD42024513515). Nine studies comprising 781 participants (430 treatment, 351 control) met the inclusion criteria. CoQ10 supplementation significantly improved sperm concentration (mean differences [MD]: 10.22×10⁶/mL [3.51-16.93], p=0.003), seminal volume (MD: 0.17 mL [0.03-0.31], p=0.02), total sperm motility (MD: 4.95% [1.15-8.75], p=0.01), and seminal CoQ10 levels (MD: 37.04 ng/ml [31.24-42.84], p<0.001). It also significantly increased clinical pregnancy odds (odds ratio: 6.02 [1.97-18.41], p=0.002). Subgroup analysis showed that treatment duration >3 months significantly improved sperm morphology (p<0.05). Three studies reported no adverse effects, while one noted mild, transient side effects. CoQ10 supplementation in men with IMI significantly improves semen quality, seminal CoQ10 levels, and clinical pregnancy rates, particularly when used for over 3 months. CoQ10 therapy in infertile men with IMI is generally safe, whether used alone or in combination with other antioxidants.