Impact of maternal fecal microbiota on the early development of microbial community in the neonatal meconium

Background The maternal gut microbiota is regarded as a major contributor to the establishment of the infant gut microbial community; however, the extent to which neonatal meconium microbiota reflects the maternal fecal microbiota remains unclear. Methods We prospectively collected paired fecal samples from mothers and their offspring after informed consent was obtained. Maternal fecal samples were collected within a week before delivery, and neonatal fecal samples were collected within a week after birth. Fecal microbial compositions were analyzed using 16S-based microbiome taxonomic profiling. Mother–newborn pairs were stratified according to concordance or discordance of the dominant bacterial phylum, and associated perinatal characteristics were analyzed. Results A total of 21 maternal-newborn pairs, comprising 21 mothers and 25 neonates, were included in the analysis. Firmicutes was the predominant phylum in both maternal and neonatal samples, with 12 of 21 pairs (57.1%) exhibiting concordant dominant phyla. Neonatal meconial microbiota showed significantly lower species richness and diversity compared with maternal stool microbiota (Wilcoxon rank-sum, P  < 0.05). At the species level, maternal and neonatal fecal microbiota communities formed clearly distinct clusters in ordination analyses, with significant differences in overall community composition (PERMANOVA, P  = 0.001). No statistically significant associations were observed between maternal or neonatal characteristics and concordance of dominant phyla within the pairs. Conclusion These findings suggest that the maternal gut serves as a partial source for early intestinal microbiota formation of the offspring, independent of delivery mode or feeding type. However, additional factors are likely to contribute to the early development of the neonatal gut microbiota.