Association Between Gut Microbiota and Postpartum Depression: A Bidirectional Mendelian Randomization Study

Backgrounds Empirical investigations have shown an association between gut microbiota and postpartum depression (PPD); nevertheless, the precise cause-and-effect relationship between these two variables remains ambiguous. This research aimed to examine the possible reciprocal causal relationship between the gut microbiota and PPD. Methods In this work, we used Mendelian randomization (MR) to analyze the relationship between the gut microbiota (n = 18,340) and PPD (n = 67,205). We obtained the relevant SNPs from publicly accessible genome-wide association studies (GWAS). The SNP estimations were combined by the inverse-variance weighted (IVW) method, including sensitivity analyses such as weighted median, MR Egger, and MR Pleiotropy Residual Sum and Outlier (PRESSO). Results We have identified strong correlations between six bacterial characteristics and the likelihood of developing PPD. Our research revealed that the genus Ruminococcaceae UCG010, the family Veillonellaceae, and the class Clostridia had a beneficial effect on preventing PPD. The class Alphaproteobacteria, genus Slackia, and order NB1n were found to have a significant negative impact on PPD. The sensitivity studies conducted on these bacterial features consistently confirmed these findings. Limitations It is crucial to acknowledge that our study was conducted just within a European society, which may restrict its applicability to other groups. Conclusions The findings from our MR investigation indicate a potential causal relationship between certain kinds of gut bacteria and PPD. Additional investigation is required to elucidate the influence of gut microbiota on the advancement of PPD.