Systematic review and meta-analysis of mean age at menarche in Iranian girls

Background: Many observational studies were published concerning the mean age at menarche and suggested those which may be a decreasing age at menarche in Iranian girls. The aim of this systematic review and metaanalysis was to estimate the overall mean age at menarche in Iranian girls. Methods: We searched using online databases through December 2014 using and examined the reference lists of pertinent paper. Finally, 28 crosssectional studies were selected for this metaanalysis. Cochran and tautwo tests were used for the detection of homogeneity of samples. The common average was calculated by random effect using RevMan 5 and Stata software. The cumulative metaanalysis and metaregression were used to review the factors affecting heterogeneity. Results: The mean age at menarche was13.9 years before 2000 and after 2000 was 12.6 years. The overall mean (95% CI) age at menarche was calculated 12.872 (95% CI: 12.874, 12.870) years based on stochastic models. Conclusion: These findings indicated that the mean age at menarche in Iranian girls was less than that of the region and developing countries therefore performing a systematic review and metaanalysis to evaluate related factors that influence age at menarche in Iranian girls could be beneficial.