Effects of folic acid and folic acid plus zinc supplements on the sperm characteristics and pregnancy outcomes of infertile men: A systematic review and meta-analysis

作者：Xiang Li, You-man Zeng, Yudi Luo, Juan He, Bowen Luo, Xiong-cai Lu, Lingling Zhu · 发表于：Heliyon · 年份：2023 · DOI：10.1016/j.heliyon.2023.e18224 · 被引用次数：20 · 研究领域：Sperm and Testicular Function、Trace Elements in Health、Iron Metabolism and Disorders

Background Folic acid and zinc supplements have been used to treat male infertility, but their efficacy is still debated. Objective To systematically evaluate the effects of folic acid and folic acid plus zinc supplements on sperm characteristics and pregnancy outcomes of infertile men. Methods An online systematic search was performed using PubMed, Cochrane Library, and EMBASE databases from inception to August 1, 2022. The goal was to identify randomized controlled trials (RCTs) that used folic acid or folic acid plus zinc to improve sperm characteristics of infertile men. Data were extracted by two investigators who independently screened the literature and assessed for quality according to the criteria. The meta-analysis was performed using RevMan 5.4 software. Results A total of 8 RCT studies involving 2168 patients were included. The results showed that compared with the controls, folic acid significantly increased sperm motility (MD, 3.63; 95% CI, −1.22 to 6.05; P = 0.003), but did not affect the sperm concentration (MD, 2.53; 95% CI, −1.68 to 6.73; P = 0.24) and sperm morphology (MD, −0.02; 95% CI, −0.29 to 0.24; P = 0.86) in infertile men. Folic acid plus zinc did not affect sperm concentration (MD, 1.87; 95% CI, −1.39 to 5.13; P = 0.26), motility (MD, 1.67; 95% CI, −1.29 to 4.63; P = 0.27), and morphology (MD, −0.05; 95% CI, −0.27 to 0.18; P = 0.69) in infertile men. Secondary results showed that compared with a placebo, folic acid alone had a higher rate of pregnan...