Association between apolipoprotein E gene polymorphism and the risk of recurrent pregnancy loss: a meta-analysis.

ABSTRACT

PURPOSE: The association between apolipoprotein E (ApoE) gene polymorphism and the risk of recurrent pregnancy loss (RPL) remains controversial. The present meta-analysis was performed to derive a precise estimate of the relationship. METHOD(S) We searched the PubMed, Embase, and Web of Science data- bases for studies related to the association between the ApoE genotype and the risk of RPL. We estimated the summary odds ratio (OR) with 95% confidence interval (CI) to assess the association. RESULT(S) Seven studies, including 2,090 RPL cases and 742 control samples, were identified. The results showed a significant association between ApoE E4 mutation and RPL risk (for E4 allele OR =1.98, 95 %CI =1.14-3.43, P=0.499; for E2E3 vs. E3E3 OR =1.33, 95%CI =1.12-1.42, P=0.008; for E2E4 vs. E3E3 OR =1.26, 95 % CI =1.07-1.49, P=0.005). CONCLUSION(S) The meta-analysis suggests an association between ApoE E4 mutation and increased risk of RPL.