Developmental Ecology of the Human Microbiome - Restoration Study of babies.

Humans are the only mammals that interrupt exposure of newborns to maternal vaginal microbiota with cesarean birthing, increasingly practiced in many countries. Babies delivered by C-section acquire a microbiota that differs significantly from that of vaginally delivered infants, and C-section delivery has been associated with increased risk for immune and metabolic disorders. Here we present a pilot study that partially restores the natural primary microbiota of infants delivered by C-section by exposing them to maternal vaginal fluids at birth. Similar to vaginally delivered babies, the gut, oral, and skin microbiome of these newborns during the first month of life was enriched in vaginal bacteria absent in unexposed C-section infants. Our results demonstrate that many vaginal microbes can be restored at birth in C-section delivered babies.