A large-scale causal analysis of gut microbiota and endometriosis associated infertility: A Mendelian randomization study

Endometriosis is a prevalent condition with notable impacts on fertility. Recent studies have implicated gut microbiota in the development of endometriosis associated infertility (EAI). This study employs Mendelian randomization (MR) to elucidate the causal relationship between specific gut microbes and EAI. Using MR, we selected single nucleotide polymorphisms associated with 211 gut microbiota taxa from large-scale genome-wide association studies summary data. We applied statistical methods including inverse variance weighting, weighted median, and MR-Egger for analysis. Outliers were identified through the leave-one-out method. MR-Egger intercept tests were conducted to address horizontal pleiotropy, while Cochran Q and P values assessed heterogeneity. The false discovery rate method was used for multiple testing correction. Sensitivity analysis and F statistics evaluated the reliability and potential biases of our results. The inverse variance weighting method indicated a significant association of the genus Actinomyces (OR = 1.657, 95% CI: 1.187-2.312, P = .00298) with an increased risk of EAI. Conversely, genera Holdemania (OR = 0.630, 95% CI: 0.444-0.894, P = .00969) and Ruminococcaceae NK4A214 group (OR = 0.689, 95% CI: 0.481-0.999, P = .0439) appeared as protective factors. MR-PRESSO global test and MR-Egger regression indicated no significant horizontal pleiotropy (P > .05). Leave-one-out analysis confirmed the robustness of these findings. Our study provides evidence of a causal relationship between specific gut microbiome taxa and EAI. These findings offer novel insights and may guide the development of new preventive and therapeutic strategies for managing EAI.