Association between serum folate level and cervical cancer: a meta-analysis.

PURPOSE: The aim of this study was to evaluate the association between serum folate level and cervical cancer. METHODS: PubMed, Medline, Springer, Elsevier Science Direct, Cochrane Library and Google scholar were searched for relevant trials. Rev.Man5.1 and Stata 11.0 software were applied for this meta-analysis. Odds Ratio (OR) and 95 % confidence intervals (95 % CI) were collected and calculated in a fixed-effects model or a random-effects model when appropriate. Subgroup analysis was performed by sample size, participant's geographical location and definition of deficient serum folate level. RESULTS: A total of 6 case-control studies including 2383 participants were included in the meta-analysis. The overall meta-analysis showed that there were significant differences between cases and controls, suggesting that deficient serum folate level was associated with the increased risk of cervical cancer. After stratification subgroup analysis, significant difference was also found in subgroup with sample size <500 as well as in Asian population, but not in subgroup with sample size ≥500, American populations as well as different definition of deficient serum folate level (<6.4 ng/ml or others). CONCLUSIONS: Based on our meta-analysis, deficiency of serum folate level was associated with the increased risk of cervical cancer among Asian populations.