Role of tumor necrosis factor‐alpha ‐238 G>A promoter region polymorphism on recurrent miscarriage: An association study and meta‐analysis

BackgroundRecurrent miscarriage (RM) is defined as the loss of two or more consecutive pregnancies. A functional SNP, ‐238G>A in the promoter region of TNF‐α, affects the gene transcription activity with implications on human pregnancy. Previous limited studies, linking the TNF‐α ‐238 G>A to the risk of recurrent miscarriage have been inconclusive.Material and methodThe PCR‐RLFP technique was used to evaluate this polymorphism in 199 RM cases and 215 control women from Amritsar, Punjab. For a meta‐analysis, a total of 13 eligible studies (including the present study) comprising 2947 cases and 2933 controls were included. To evaluate the association among different genetic models, odds ratio with a 95% confidence interval (CI) and chi‐square were used.ResultsGenotype and allelic frequency did not differ significantly between both groups (p = .07 and p = .24, respectively). In the present meta‐analysis, a significant association was found with the recessive model (OR‐1.78 CI:1.24–2.55, p = .002).ConclusionAlthough, TNF‐α ‐238 G>A polymorphism did not provide any risk in the case‐control study but provided risk towards the development of RM with the recessive genetic model in the pooled analysis.