Vertical Transmission of Gut Dysbiosis From Mothers With Gestational Diabetes to Infants

Background

Vertical transmission of microbes from a mother's gut to their offspring plays a crucial role in the genesis of the early life gut microbiome. Gestational Diabetes Mellitus (GDM) is the commonest metabolic disorder during pregnancy, which has adverse short- and long-term effects on both maternal and infant health. We aimed to capture the GDM-associated biosignatures in infants' gut microbiome from birth to the first 6 weeks of life.

Methods

53 GDM mother-infant dyads and 16 healthy mother-infant dyads were recruited. We performed targeted 16S rRNA gene amplicon sequencing on stool samples. Various statistical analyses were performed to understand the changes in the microbiome profile of infants and identify GDM-associated bacterial biomarkers in mothers and their transfer to infants.

Results

GDM altered the gut microbiome of pregnant women as compared to healthy counterparts (PERMANOVA, p.adjusted < 0.05), with predominance of bacterial members associated with insulin resistance, proinflammatory conditions, and other metabolic processes. Infants born to GDM mothers have distinctive early life microbiome (meconium and six weeks stools) compared to infants born to control mothers (PERMANOVA, p.adjusted < 0.05). We also identified the presence of various GDM-associated microbial signatures such as Blautia and Collinsella in both meconium and one-month-old stool samples of infants born to GDM mothers.

Conclusion

This study provides a better understanding of the impact of GDM on the seeding of a specific set of microbes during the early life colonization event in the infant gut that increases the risk of inflammatory and metabolic diseases in the future.