Short-term temporal variation in the early-life gut microbiota links maternal clinical phenotypes to neonatal jaundice.

BACKGROUND

Maternal clinical phenotypes shape the neonatal gut microbiome and influence infant health outcomes, yet the microbial mechanisms linking maternal conditions to neonatal jaundice remain largely unknown. To investigate this, we characterized bacterial community profiling in prenatal maternal feces, meconium, and postnatal Day 3 neonatal feces from a mother-infant cohort, and integrated microbiota-phenotype association analyses and mediation models.

RESULTS

We found that meconium microbiota showed slightly lower divergence from maternal fecal microbiota than neonatal fecal microbiota did. Canonical correspondence analysis (CCA) showed that maternal HbA1c consistently contributed to early-life gut microbial community structure, explaining 7% of the variation in meconium microbiota and 11% of the variation in neonatal fecal microbiota. Neonatal transcutaneous bilirubin levels on Day 3 were also associated with early-life microbial variation, with a stronger association observed in neonatal fecal microbiota than in meconium. In addition, maternal HbA1c significantly correlated with maternal urinary bacterial counts. The abundance distribution patterns of meconium ASVs related to maternal diabetes status and urinary bacterial detection status were also observed in the corresponding taxa of neonatal gut microbiota and were associated with subsequent neonatal jaundice. Notably, specific differentially abundant ASVs affiliated with Bifidobacterium, Clostridium_T, and Rothia mediated the interconnected rather than independent effects of maternal HbA1c and urinary bacterial counts on neonatal jaundice.

CONCLUSIONS

The results suggest that meconium microbiota features associated with maternal diabetes-related phenotypes influence early neonatal gut microbial community structure and may contribute to neonatal jaundice. This study highlights the potential role of early-life gut microbiota shifts in mediating the effects of maternal physiological variation on neonatal health outcomes.