Aim: Genetic polymorphisms in homocysteine-related genes are subject of a large body of research in pregnancy and newborn associated pathologies. The enzyme cystationine β-synthase (CBS) is involved in the transsulfuration pathway of homocysteine to cysteine. Our objective was to analyze the association of a common polymorphism exhibited by the CBS gene, 844ins68, with idiopathic spontaneous abortions (SA). Material and Methods: 131 patients with a history of at least one unexplained SA and 135 healthy women with at least one successful pregnancy and no SA were included in a case-control study. Simplex PCR was used to genotype the cases and control volunteers for the CBS 844ins68 polymorphism. Fisher’s exact test was performed to obtain the odds-based parameters describing the relationship between the two variables. Results: The variant allele was encountered with a frequency of 0.08 in the SA group and 0.048 in controls. The dominant model analysis of risk revealed the OR 1.957, 95%CI [0.920, 4.162], Fisher’s p = 0.09. Conclusion: The findings suggest possible effects of this polymorphism in SA risk that did not reach the significance level in this study. Future studies might validate or clarify the association between CBS 844ins68 and idiopathic SA.


Cystathionine β-synthase, Genetic polymorphism, Spontaneous abortion