Maternal and infant microbiota in early infancy: Longitudinal findings from a randomised controlled trial.

Breast milk microbiota showed a significant compositional temporal shift over the first 8 weeks postpartum.

• Beta diversity analysis revealed a statistically significant compositional change in breast milk microbiota (p = 0.039).
• This temporal shift was driven primarily by changes in the control group rather than the intervention group.
• Alpha diversity metrics remained stable across all sample types including breast milk.
• Samples were collected at 1 week and 8 weeks postpartum.

Infant gut microbiota composition changed over the first 8 weeks postpartum, with increased Bifidobacterium and decreased Staphylococcus and Enterobacteriaceae.

• Relative abundance of Bifidobacterium increased in infant stool from 1 to 8 weeks postpartum.
• Relative abundance of Staphylococcus and Enterobacteriaceae decreased in infant gut over the same period.
• Alpha diversity metrics in infant gut remained stable despite compositional changes.
• Infants were exclusively breastfed throughout the study period.

Maternal gut microbiota remained stable in both diversity and composition over the first 8 weeks postpartum.

• Both alpha and beta diversity metrics in maternal stool showed no significant changes from 1 to 8 weeks postpartum.
• Relative abundance of dominant genera in maternal gut also remained stable.
• Mothers were vaginally delivered at 34+0 to 37+6 weeks gestation.
• Mothers were practising traditional postpartum confinement during the study period.

A significant reduction in Staphylococcus in breast milk was observed in the maternal relaxation intervention group only.

• The reduction in Staphylococcus relative abundance in breast milk was specific to the intervention group and not observed in the control group.
• This finding suggests that a maternal stress-reduction intervention may influence breast milk microbiota composition.
• The study was a randomised controlled trial of a maternal relaxation intervention.
• Authors note that further research is warranted to confirm these effects and investigate mechanisms.

The study followed vaginally delivered mothers of late preterm and early-term infants and their exclusively breastfed infants from 1 to 8 weeks postpartum.

• Gestational age range was 34+0 to 37+6 weeks.
• This was a secondary analysis drawing on data from a randomised controlled trial of a maternal relaxation intervention.
• Maternal stool, breast milk, and infant stool samples were collected at both 1-week and 8-week time points.
• Microbiome analysis was performed via 16S rRNA gene amplicon sequencing.
• Changes in alpha diversity, beta diversity, and relative abundance of dominant genera were assessed overall and by intervention group.