Review links gut microbiota dysbiosis to recurrent spontaneous abortion in reproductive-age couplesGut bacteria linked to recurrent pregnancy loss

This review evaluates the relationship between gut microbiota dysbiosis and recurrent spontaneous abortion in reproductive-age couples. The scope includes analysis of microbial composition changes observed in this population. The authors synthesize data showing decreased alpha diversity and reduced levels of Bacteroidetes, Lactobacillus, and Bifidobacterium. Conversely, elevated levels of Proteobacteria and Escherichia-Shigella were also noted in the reviewed literature. No specific effect sizes or absolute numbers were reported for these outcomes. The review does not report adverse events or sample sizes for the primary studies included in the synthesis. The authors acknowledge inconsistent findings across the included studies as a key limitation. Funding sources and conflicts of interest were not reported in the source material. The review suggests microbiota-targeted strategies may be relevant for unexplained recurrent spontaneous abortion. However, the evidence remains observational regarding the bidirectional causal relationship between gut dysbiosis and RSA. Clinicians should interpret these associations with caution given the noted inconsistencies and lack of reported certainty metrics.