Babies delivered by caesarean section are slower to acquire certain types of “good bacteria” in their gut and have higher levels of potentially problematic bacteria than those born vaginally, researchers say, according to The Guardian.
A study of more than 100 babies showed that those born vaginally had a very different make-up of their gut microbiome (clusters of gut microbes), potentially making caesarean babies more prone to respiratory infections. The differences were found to reduce as the babies grew older.
Previous studies have suggested that the mode of delivery affects the newborn’s microbiome, but some said this might be because many mothers who have had caesarean sections require antibiotics.
The new research, which will be presented at the European Congress of Clinical Microbiology and Infectious Diseases in Amsterdam, backs up claims that it is specifically the mode of delivery that drives the differences.
The research involved the team collecting faeces at 10 points in the year from 46 babies born by caesarean section and 74 babies born vaginally, starting from their first faeces, and analysing its microbial makeup.
Crucially, the team says that antibiotics, if needed, were only given to mothers once the baby was delivered – meaning babies were not directly exposed to the antibiotics.
The results, based on analysis of stool both from the mothers and the babies, also showed that babies born by caesarean section were slower to acquire certain “good bacteria” that are important in digesting milk, and had higher levels of certain types of potentially harmful bacteria than those born vaginally.
“We feel that it is proved that mode of delivery is an important driver or modifier of the gut microbiome in young infants,” said Prof Debby Bogaert from the University of Edinburgh, who worked on the project with colleagues in the Netherlands.
She added that the conclusion was backed up by findings that antibiotics given to mothers after delivery did not appear to affect their own gut microbiome, and that differences in babies’ microbiomes were also seen in babies that were only bottle-fed, suggesting the effects were not down to babies receiving antibiotics through breast milk.