The Association Between MTHFR C677T Gene Polymorphism and Repeated Pregnancy Loss in Arabic Countries: a Systematic Review and Meta-Analysis.

The role of MTHFR C677T polymorphism in repeated pregnancy loss (RPL) among different populations has been studied with inconsistent results. The study objective was to determine the association between MTHFR C677T polymorphisms and RPL among Arab women. The review included all the available studies investigating the association between MTHFR C677T polymorphism and RPL from 2000 until now. The searched database included Cochrane, Trip, EMBASE, and Google Scholar. Two authors independently reviewed the searched articles for eligibility, judged their risk of bias, and extracted the characteristics of the studies. Review Manager 5.3 program was used for data analysis using odds ratio (OR) at a 95% confidence interval (CI). The study revealed a statistically significant difference between cases and controls regarding combined MTHFR C677T polymorphisms (OR = 1.50, 95% CI = 1.15-1.96), MTHFR C677T heterozygous (OR = 1.41, 95% CI = 1.08-1.83), and MTHFR C677T homozygous (OR = 4.19, 95% CI = 1.87-9.39). Considerable significant heterogeneity was recorded in the three analyses (P < 0.05). The review supported the hypothesis that MTHFR C677T mutation is considered a significant risk factor for RPL among Arab women.