The Effect of Folate and Folate Plus Zinc Supplementation on Endocrine Parameters And Sperm Characteristics in Sub Fertile Men: A Systematic Review And Meta-Analysis

Backgournd: To evaluate the effect of folate and folate plus zinc supplementation on endocrine parameters and sperm characteristics in sub fertile men. We conducted a systematic review and meta-analysis. Electronic databases of Medline, Scopus, Google scholar and Persian databases were searched from 1966 to 2016 using a set of relevant keywords including folate or folic acid AND (infertility, infertile, sterility).All available (RCTs), conducted on a sample of sub fertile men with semen analyses, who took oral folic acid or folate­­ plus­­ zinc, were included. Data collected included endocrine parameters and sperm characteristics. Statistical analyses were done by Comprehensive Meta-analysis Version Results: In total, seven studies were included. Six studies had sufficient data for meta-analysis. Sperm concentration was statistically higher in men supplemented with folate than with placebo (p<0.001) . However, folate supplementation alone did not seem to be more effective than the placebo on the morphology (P=0.056) and motility of the sperms (P=0.652). Folate plus zinc supplementation did not show any statistically different effect on serum testosterone (P=0.86), inhibin B (P=0.84), FSH (P=0.054), and sperm motility (P=0.169) as compared to the placebo. Yet, folate plus zinc showed statistically higher effect on the sperm concentration (P<0.001), morphology (p<0.001), and serum folate level (P<0.001) as compared to the placebo. Folate plus zinc supplementation had a positive effect on sperm characteristics in sub fertile men. However, these results should be interpreted with caution due to the important heterogeneity of the studies included in this meta-analysis. Further trials are still needed to confirm the current findings.

کلیدواژه ها:

Folate ، Folic Acid ، Zinc Sulfate ، Male Infertility ، Sub Fertility ، Sperm ، Endocrine