Objective: The main objective of this study was to determine the association of variation of matrix metalloproteinase (MMP) and tissue inhibitors of metalloproteinase (TIMP) genes and the etiology of idiopathic recurrent spontaneous abortion (IRSA). Additionally, the association of variability in the afore-mentioned genes and susceptibility to primary and secondary IRSA was investigated. Patients: Two groups of cases were included in this study, including the group of couples with IRSA and control group. A total of 149 women and 149 of their reproductive partners with three or more consecutive spontaneous abortions of unknown etiology comprised the group of couples with IRSA. The control group included 149 healthy women and 149 healthy men with at least two live births and no history of pregnancy losses or any other pregnancy complications. Methods: Genotyping of MMP-1 -1607 1G/2G, MMP-2 -735 C/T, MMP-2 -1306 C/T, MMP-3 -1612 5A/6A, MMP-9 -1562 C/T, as well as TIMP-1 -372 C/T, TIMP-2 -303 C/T, TIMP-3 -915 A/G, TIMP-3 -1296 C/T and TIMP-4 -3'-UTR C/T polymorphisms was performed using the combination of polymerase chain reaction and restriction fragment length polymorphism methods. Results: Statistically significant higher frequency of individual MMP-2 -735 CT (P=0.006), MMP-2 -1306 CC (P=0.037) and MMP-9 -1562 CC (P=0.010) genotypes was found in women with IRSA compared with control women. Moreover, twofold increased odds of IRSA were determined in women with MMP-2 -735 CT and TT compared to CC genotype (OR=2.15; 95 % CI=1.34-3.45; P=0.001), MMP-2 -1306 CC compared to CT and TT genotypes (OR=2.08; 95 % CI=1.17-3.69; P=0.012), as well as MMP-9 -1562 CC compared to CT and TT genotypes (OR=2.21; 95 % CI=1.30-3.80; P=0.004). Combined analysis of these risk genotypes, as well as their combination with genotypes of other MMP and TIMP gene polymorphisms did not increase the odds of IRSA in comparison with individual MMP-2 and -9 risk genotypes. No statistically significant differences were determined in the distribution of genotypes, alleles and haplotypes frequencies of other MMP and TIMP gene polymorphisms between IRSA patients and controls. A statistically significant higher frequency of MMP-9 -1562 CC genotype was found in male partners of women with secondary IRSA compared with primary IRSA (P=0.015). Men with MMP-9 -1562 CC genotype had 3,81 increased odds of secondary IRSA compared to men with CT and TT genotypes (95 % CI=1.47-9.84; P=0.006). The combinations of MMP-9 -1562 CC genotype with genotypes of other MMP and TIMP gene polymorphisms did not increase the odds of IRSA. No significant differences were found in the distribution of genotypes, alleles and haplotypes frequencies of other MMP and TIMP gene polymorphisms between the patients with primary and secondary IRSA. Conclusion: Individual MMP-2 -735 CT, MMP-2 -1306 CC or MMP-9 -1562 CC genotypes could be factors of predisposition to IRSA in women. Additionally, MMP-9 -1562 CC genotype in men might be a factor of predisposition to secondary IRSA.