Caesarean section babies at risk of obesity

A new study from Harvard gives more evidence for the link between C section deliveries and obesity in children.  The study, published in the journal JAMA Paediatrics, looked a children in the Growing Up Today Study, including 22 068 offspring born to 15 271 women, followed up via questionnaire from ages 9 to 14 through ages 20 to 28 years.  Overall 13% of participants were obese.  22% were born by C section.  Those delivered by Caesarean were 15% more likely to be obese after adjusting for mothers’ weight, age and other factors.  They also looked at 13,000 siblings where one birth had been natural and one had been Caesarean and found that babies delivered by Caesarean were 64% more likely to be obese as adults than siblings born naturally.  The authors concluded “Caesarean birth was associated with offspring obesity after accounting for major confounding factors. Although additional research is needed to clarify the mechanisms underlying this association, clinicians and patients should weigh this risk when considering cesarean delivery in the absence of a clear indication.”

Reported in The Times:  “I think that our findings — particularly those that show a dramatic difference in obesity risk between those born via caesarean and their siblings born through vaginal delivery — provide very compelling evidence that the association between caesarean birth and childhood obesity is real,” Jorge Chavarro, senior author of the study, said. “That’s because many of the factors that could potentially be playing a role in obesity risk, including genetics, would be largely the same for each sibling.”  Audrey Gaskins, another of the researchers, said that if the link between C-sections and obesity was proved there might be some way to ensure babies got their dose of healthy bacteria. Vaginal “seeding”, aimed at swabbing babies with bacteria, has become popular, but doctors have said that it could cause infection.”

A UK study published in 2013 in the International Journal of Obesity looked at the medical records of more than 10,000 British children aged 11 years as part of the Avon Longitudinal Study of Parents and Children. They found that those born by C section had lower birth weights and were twice as likely to be obese than those born naturally.    The study found that a third of three-year-olds were overweight, by age seven and 15, 17% of children were obese.  They found that “the association among children born of overweight/obese mothers was strong and long-lasting. In contrast, evidence of an association among children born of normal-weight mothers was weak.”  One of the authors of this paper, Dr Blustein, also thinks there may be a link with gut bacteria as babies delivered by C section are not exposed to the same bacteria as natural deliveries.  C section babies may take longer to develop ‘good’ bacteria in their guts.  Obese adults tend to have fewer ‘good’ bacteria in their gut and higher levels of ‘bad’ bacteria, which mean they burn fewer calories and store more of them as fat.

Read More:

Read the paper here.

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