Published: Sept. 1, 2010 By

The way you were born could impact the rest of your life.

It’s been known babies born via Caesarian section can be more susceptible to allergies, asthma and certain pathogens than newborns who exit the birth canal. But a University of Puerto Rico study involving CU-Boulder and two Venezuelan institutes appears to explain why.

Babies born via the birth canal have bacterial communities that resemble their mother’s vaginal bacteria while those born by Caesarian section have common skin bacterial communities.

The study indicates that the direct transmission of the mother’s bacteria to the newborn may act as a defense against diseases by limiting the colonization of other pathogens. While C-sections can be a lifesaving procedure, they also shift the bacterial communities found on a baby, making them more prone to Staphylococcus and other infections.

“The challenge now is to fill in the rest of the story by tracking microbial communities in infants to toddlers to children and adults over weeks, months and years to see how they evolve and change,” says former CU Boulder researcher Elizabeth Costello, now at Stanford University.