A new study on the baby microbiome has shown that those who are born via a caesarean section (C-section) don’t possess the same bacteria in their gut as those who are born naturally.
The research revealed that when a baby is born naturally, it receives the majority of its first measure of bacteria from the mother. Babies born by C-section are found to have bacteria related to the hospital environment, such as strains that display antimicrobial resistance. This discovery could shed light on why babies born through C-section are more susceptible to allergies, asthma, and other immune conditions.
“How your immune system functions through your life might be influenced by its first interactions with bacteria,” says the senior author on the paper from University College London, Nigel Field. “If there are differences in longer-term health outcomes by different patterns of [bacteria], that tells us something quite important about health.”
Bacteria from the mother’s gut
Prior to the study, it was believed that babies’ microbiomes may be formed by bacteria that gets swallowed whilst they’re still in the birth canal. However, the most recent research shows that the microbiome of babies who were born naturally didn’t originate from vaginal bacteria, but rather from the mother’s gut, most likely at the time of the birth. These findings will force the medical community to reconsider the act of swabbing babies born via C-section with the mother’s vaginal bacteria.
“The practice of vaginal seeding is quite controversial,” says Peter Brocklehurst, a women’s health professor at the University of Birmingham and a co-author of the study. “Here we find no biological evidence that it would be effective anyway.”
While babies are still in their mother’s womb, they remain sterile. The moment they are subjected to the external world, they are exposed to bacteria which quickly colonizes the gut. Scientists are still uncertain as to precisely how early exposure affects immune activity; this needs to be properly detailed before this new information can be applied to clinical practices.