No association between folate intake, pregnancy outcome and single nucleotide polymorphisms in the MTHFR gene in women with unexplained infertility

Sammanfattning: Folate has a direct effect on DNA synthesis which is a major factor in embryo development. In 10% of all infertility couples, there is no apparent cause of infertility. One theory is that folate metabolism is affected in these couples and that it is a possible cause of infertility. This study has analyzed three single nucleotide polymorphisms in the gene MTHFR - rs1801131, rs1801133 and rs2274976. Evaluation of the relationship between folate intake, gene variations and pregnancy outcomes were also performed. For the analysis, blood samples from women diagnosed with infertility (n = 297) and a control group of fertile women (n = 193) was used. Genotyping was performed by using TaqMan SNP genotyping assays. The results showed no significant group difference in genotype or allele frequencies. In addition, there were no differences between genotypes and pregnancy outcomes, or between folate intake and pregnancy outcome. Among the group of women with diagnosed infertility who had children (through IVF), there was more women who had low folate levels (n = 39) than women with high folate levels (n = 28), but the difference was not significant. These studies suggest that disturbances in folate pathway are not an explanation for unexplained infertility.