Gut Microbiome and Serum Metabolic Alterations in Recurrent Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a common complication of pregnancy, particularly affecting multiparous women with a history of GDM, who face a recurrence risk approaching 50%. This study investigates the association between gut microbiota modifications and metabolic profiles from early to mid-pregnancy and the recurrence of GDM in a cohort of 70 multiparous women with prior GDM. Conducted as a prospective cohort study at Beijing Obstetrics and Gynecology Hospital from July 2018 to December 2020, participants underwent assessments including oral glucose tolerance tests (OGTT) and collection of fecal and serum samples. Microbial DNA was extracted, with the V3-V4 region of the 16S rRNA gene sequenced, while serum metabolites were analyzed through non-targeted metabolomics using mass spectrometry. Results indicated significant alterations in gut microbiota composition, with specific genera associated with increased GDM risk. Notably, the study identified distinct metabolic patterns, revealing downregulation of several key metabolites in recurrent GDM cases compared to controls. Pathway enrichment analysis highlighted dysregulation in metabolic functions pertinent to serotonergic synapses, arachidonic acid metabolism, unsaturated fatty acid biosynthesis, and caffeine metabolism. Overall, this research underscores the critical role of gut microbiota and metabolic changes in understanding GDM recurrence, providing insights that may inform targeted preventive strategies.