ABSTRACT: The aim of this study was to determine whether interleukin-6 (IL-6) -174 G/C, IL-6 -634 G/C, and interferon-? (IFN-?) +874 A/T polymorphisms are associated with susceptibility to recurrent pregnancy loss (RPL).We conducted a literature search using PubMed and EMBASE databases and performed a meta-analysis using fixed- or random-effects models.A total of 15 articles met the study inclusion criteria. When all study subjects were considered together, meta-analysis showed no association between RPL and the IL-6 -174 GG?+?GC genotype (odds ratio [OR]?=?0.794, 95 % confidence interval [CI]?=?0.542-1.163, p?=?0.236). However, stratification of the data by ethnicity indicated an association between this genotype and RPL in non-Caucasians (OR?=?0.528, 95 % CI?=?0.302-0.925, p?=?0.028), but not in Caucasian populations. Moreover, meta-analysis revealed an association between RPL and the IL-6 -634 GG?+?GC genotype in all study subjects (OR?=?0.556, 95 % CI?=?0.383-0.806, p?=?0.002), while stratification by ethnicity revealed a negative association between this genotype and RPL in Asian (OR?=?0.545, 95 % CI?=?0.371-0.800, p?=?0.002) but not Middle Eastern populations. Furthermore, a relationship between the IFN-? +874 A allele and RPL was identified in non-Caucasians (OR?=?1.403, 95 % CI?=?1.133-1.734, p?=?0.002), but not in Caucasians.This meta-analysis demonstrates that IL-6 -174 G/C, IL-6 -634 G/C, and IFN-? +874 A/T polymorphisms are associated with susceptibility to RPL, particularly in non-Caucasians.