Micronutrient supplementation in improving semen quality: Systematic review and meta-analysis

Background: One of the major pathophysiology linked to male infertility is oxidative stress. Due to its antioxidant properties, micronutrient supplementation has been shown to lower oxidative stress in critically ill patients. Recent meta-analysis revealed the significance of micronutrients, but no long-term fertility outcomes were reported in the study. Purpose: This study investigates the role of micronutrient supplementation in improving semen quality, hormonal parameters, and fertility outcomes in male with infertility. Methods: Databases include PubMed, Cochrane, Scopus, ProQuest, and MEDLINE followed by citation searching until August 2024. The risk of bias was assessed using the Cochrane Risk-of-Bias Tool 2 (RoB2) and the ROBINS-I tool for intervention studies. Data synthesis was carried out using R Studio software. Results: A total of 35 studies were included for analysis. Semen volume was lower in patients receiving vitamin E (MD −0.27 mL, 95% CI −0.49, −0.04; p = 0.02). A combination consisting of L-carnitine, L-arginine, coenzyme Q10, and zinc was associated with higher sperm count (MD 9.44 mil, 95% CI 1.30, 17.59; p = 0.02). Folic acid was associated with higher sperm count (MD 4.27 mil, 95% CI 2.61, 5.93; p < 0.01). No significant difference was seen in sperm concentration, sperm vitality, proportion of sperm with normal morphology, sperm total motility, DNA fragmentation, hormonal parameters (i.e. Follicle-Stimulating Hormone (FSH), Luteinizing Hormone (LH), testosterone), and fertility outcomes between micronutrients and control groups. Conclusion: Micronutrient supplementation using antioxidants (i.e. L-carnitine, L-arginine, coenzyme Q10), vitamins, and folic acid may improve sperm parameters in males with infertility. Level of evidence Level 1 and 2