Colonisation of the gut by bifidobacteria is much more common in vaginal deliveries than Caesarean sections
2015
Abstract
Micro-organisms start to colonise the infant gut during the first days of life and play an important role in human health throughout life. More than 10/12 bacteria per gram of intestinal content present a barrier against colonisation by pathogens and alien microbes.
They are involved in metabolism by degrading nondigestible food remnants, producing vitamins B and K and participating in short-chain fatty-acid metabolism. These bacteria also play a role in the stimulation and development of the immune system.
Therefore, the colonisation of a newborn infant's gut is vital and it has a significant influence on the final composition of the resident microbiota in adults.