Effect of oral alpha-lipoic acid (ALA) on the treatment of male infertility A protocol for systematic review and meta-analysis

Background: Male fertility has gradually become a worldwide problem. Because of the limitation of treatment, many drugs have been used for improving sperm quality. Among them, alpha-lipoic acid (ALA), as a treatment of diabetic neuropathy, has been applied to improve the quality of sperm in clinical practice, with satisfactory effect. However, there is still no systematic review on the field of male infertility treating with oral ALA. Methods: The databases of MEDLINE, EMBASE, Web of Science, Clinicaltrials.org., China National Knowledge Infrastructure Database (CNKI), China Biology Medicine Database (CBM), Wan fang Database, VIP Science Technology Periodical Database, and Cochrane Library were retrieved. Grey literature will be searched in OpenGrey. Related Randomized controlled trials (RCTs) will be collected and selected before December 30, 2019. We will search English literature and Chinese literature using search terms including male infertility, semen, sperm, alpha-lipoid acid, alpha lipoid acid, lipoid acid. We will start to search database in November 20, 2019. Sperm concentration, motility and morphology, sperm DNA fragmentation index, sperm number of per ejaculate, sperm viability and adverse events will be evaluated. RevMan 5.3 and Stata 14.0 will be used for Systematic review and Meta-analysis. This protocol reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) statement, and we will report the systematic review by following the PRISMA statement. Results: Through systematic review, and meta-analysis when necessary, we can obtain the effect of ALA on sperm quality, including sperm motility, concentration, morphology and other indicators. Conclusion and dissemination: Efficacy and safety of oral ALA on male sperm quality in infertile men will be assessed. The results will be published in a public issue journal to provide evidence-based medical evidence for urologists and andrologists to make better clinical decisions.