Infants born vaginally have a different set of gut bacteria than the babies that are born by C-section. This happens because, after an infant is born vaginally, he/she passes through the mother’s birth canal and is bathed with all the microbes and bacteria present. Whereas during C-section, the baby gets rubbed with the swabs (placed in the mother’s vagina during C-section) all over the face and body, including eyes and mouth by the doctors. The purpose of this procedure is to give the same bacteria the baby would get through vaginal birth. However, contrary to these goals, scientists from Wellcome Sanger Institute found out that babies born via C-section did not get most of their gut bacteria from mothers but had more bacteria associated with the hospital environment in their guts. 

There have been many discussions and clinical trials regarding the role of the infant’s gut bacteria in their later health. At least four groups of researchers from the US, Sweden, and China have begun different experiments in which they are swabbing hundreds of C-section babies with their mother’s microbes while comparing them to a control group. The aim of these studies is to learn how gut bacteria and microbes in the bodies of the babies might influence their allergy risk and chronic health conditions in the future. 

The whole concept of “during birth, the kind of bacteria the baby intake affects its health” gained motion when a microbial ecologist Maria Gloria found out that babies delivered surgically absorbed different collections of bacteria than those born vaginally. It was found that C-section babies that comprised 30% of births in the United States are more prone to obesity and immune diseases such as diabetes. 

For now, there are no assured pieces of evidence to confirm that differing exposure to vaginal microbes at birth can help explain variation in people’s health over time. David Aronoff, a researcher at Vanderbilt University in Nashville explains that differences in the microbe exposure at birth and later health could be caused by other factors, such as kinds of antibiotics a mother takes during pregnancy and surgery, breastfeeding, genetic predisposition to obesity, DNA sequencing and much more. The largest study of neonatal microbiomes published in Nature disclosed that the microbiome of vaginally delivered newborns did not come from the mother’s vaginal bacteria, but from the mother’s gut. This questioned the whole practice of swabbing babies with vaginal bacteria after C-section. 

Gut Microbiome is a complex system of millions of microbes and is one of the most important sources for the development of the immune system. If the right amount of exposure to proper microbes is not given in early childhood, it can create vulnerability to diseases such as asthma, allergies, and diabetes over time. On the other hand, the effect of the initial gut microbiome on the overall immune system development and health is not fully explored and understood.

Intervening with the natural interactions between babies and bacteria is a high-risk process, and therefore it should be done with careful analysis and urgent necessity. Many other factors should also be considered and studied in order to find out why the C-section babies are statistically more prone to develop allergies, chronic inflammatory diseases, and metabolic diseases.