The Impact of Microbiota-Mediated Immune Regulation on Recurrent Pregnancy Loss and Intervention Strategies

Recurrent pregnancy loss (RPL) significantly affects reproductive health in couples of childbearing age. Its pathogenesis is complex, with nearly 50% of cases remaining unexplained, and immune regulation plays a key role in its development. This review focuses on the relationship between human microbiota (gut, reproductive tract, and endometrial microbiota), immune regulation, and RPL, systematically summarizing related research progress. RPL patients exhibit characteristic changes in the gut, reproductive tract, and endometrial microbiota, such as reduced gut microbial diversity, decreased beneficial bacteria, increased harmful bacteria in the reproductive tract, and an imbalanced endometrial microbiota structure. Dysbiosis can lead to immune regulation abnormalities, increasing the risk of RPL by disrupting immune tolerance, triggering inflammatory responses, and interfering with metabolism. Although microbiota-based interventions, such as probiotics, prebiotics, and fecal microbiota transplantation, show potential, they face challenges related to strain selection, donor screening, and unclear mechanisms. Current research also faces limitations in detection technology and sample size, and the understanding of the microbiota-immune-RPL relationship requires further deepening. Future studies should clarify causal relationships using advanced technologies, develop more effective detection and intervention methods, and create personalized treatment plans based on individual patient characteristics to improve clinical diagnosis and treatment of RPL and safeguard women's reproductive health.