Maternal Gestational Diabetes and the Neonatal Gut: Evidence of Dysbiosis Transfer

Abstract

Gestational diabetes mellitus (GDM) alters maternal metabolism and inflammation in late pregnancy, conditions that can reshape the intestinal microbiome and, potentially, the founding microbiota of the newborn. This narrative review synthesizes recent cohort and mechanistic studies on vertical transmission of dysbiosis from mothers with GDM to their infants. Evidence from 16S rRNA sequencing and metagenomics suggests reduced alpha diversity and enrichment of opportunistic taxa (e.g., Enterobacteriaceae) in GDM mothers, with concordant signatures in neonatal stool during the first weeks of life. Proposed pathways include in utero exposure to hyperglycemia-driven inflammatory mediators, altered microbial metabolite profiles, and delivery-mode–dependent transfer at birth. Early-life dysbiosis has been associated with accelerated weight gain, impaired glucose homeostasis, and heightened risk of atopic disease, underscoring the importance of perinatal prevention. We summarize modifiable factors—dietary fiber, targeted probiotics, intrapartum antibiotic stewardship, and breastfeeding—that may mitigate risk while highlighting gaps in causal inference and standardization of microbiome endpoints. Pragmatic trials integrating microbiome readouts with maternal glycemic targets are a priority.