Search icon


07th Sep 2016

Babies Born By C-Section ‘More Likely To Be Obese’

Katie Mythen-Lynch

Babies born by Caesarean section are fifteen percent more likely to be obese as adults than babies delivered vaginally. 

In fact, when compared with siblings delivered vaginally, C-section babies are 64 per cent more likely to be obese than their brothers and sisters.

That’s according to the results of a major new Harvard University study involving 16 years of data from more than 22,000 young adults who took part in Growing Up Today research.

Speaking about the eye-opening findings, published in JAMA Pediatrics, coauthor Audrey Gaskins of Harvard’s T.H. Chan School of Public Health told ResearchGate:

“We found that individuals born by cesarean were more likely to become obese as children and adolescents, and to remain obese as young adults.

“What makes our findings compelling and different from previous studies addressing this question, is that this was also true when we compared siblings who differed in type of delivery—one was born by cesarean and the other by vaginal delivery—and when restricted to women without any known risk factors for having a cesarean, some of whom may have undergone elective cesarean.”

Gaskin and her colleagues believe that the difference lies in the gut microbiota that colonise our bodies at birth.

“Children born by vaginal delivery are primarily exposed to their mothers’ vaginal and gut microbes, whereas children born by cesarean are primarily exposed to bacteria on their mothers’ skin and whatever bacteria happen to be in the air in the operating room.” she explains.

“This initial difference in mode of delivery leads to changes in the type of bacteria living in children’s guts. Moreover, the pattern of gut bacteria that children born by C-section tend to have has been previously linked to greater risk of obesity later in life.”

Gaskins is keen to point out that Caesareans “are an essential and lifesaving procedure in many cases, but they are not always necessary—and they are not risk free”.

“If there is not a clear medical or obstetric indication for having a cesarean delivery, women should talk with their doctors about the potential risks to both themselves and their children, one of which is a higher risk of obesity for the child.” she adds.

According to HSE figures, more than 25 percent of women in Ireland give birth via Caesarean, far exceeding the World Health Organisation’s recommended rates of 10-15 percent.

For more information, read the HSE recommendations