Microbiome Maturation Trajectory and Key Milestones in Early Life

The gut microbiome undergoes rapid maturation during the first 1,000 days of life, influencing long-term immune, metabolic, and neurodevelopmental outcomes. This review highlights the stages of microbial colonization from birth through early childhood, emphasizing the impact of factors such as delivery mode, type of feeding, complementary feeding, antibiotic exposure, and environmental interactions. Disruptions during this sensitive period, especially due to antibiotic use or inadequate diet, are associated with increased disease risk and alterations in microbiome composition and function. Advancing our understanding of early microbiome trajectories may enable targeted interventions to promote optimal health.