NEW ORLEANS — Risk for obesity was considerably higher for children born via Cesarean section vs vaginal delivery, researchers reported at the American Heart Association’s Scientific Sessions 2016.1

Noel Mueller, PhD, MPH, an assistant professor of epidemiology at Johns Hopkins University, and colleagues conducted a prospective analysis of data from 2045 mother-child pairs (aged 2 to 8 years) in the Boston Birth Cohort.1 They sought to assess the association between birth mode and childhood overweight and obesity, as well as the joint association of maternal prepregnancy BMI and birth mode and childhood overweight and obesity. Complete data were available for 1441 term deliveries.1

After adjustment for maternal age at delivery, race/ethnicity, education, air pollution exposure, prepregnancy BMI, pregnancy weight gain, and birth weight, results showed that children delivered via Cesarean section had 40% greater odds of becoming overweight or obese in childhood than those delivered vaginally (odds ratio [OR]: 1.4; 95% confidence interval [CI], 1.1-1.8).1

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Additionally, the researchers found that maternal BMI was also a factor. For children delivered vaginally, odds for childhood overweight or obesity were 70% greater for those with overweight mothers (OR: 1.7; 95% CI, 1.2-2.3) and 80% greater for those with obese mothers (OR: 1.8; 95% CI, 1.3-2.6) than children with normal-weight mothers.1 For children delivered via Cesarean section, however, this association was even stronger. After multivariable adjustment, odds for developing childhood overweight or obesity were more than twice as high for children born to overweight mothers (OR: 2.2; 95% CI, 1.5-3.2) and nearly 3 times as high for children born to obese mothers (OR: 2.8; 95% CI, 1.9-4.1).1

“We think that the reason for the difference may be due to the beneficial microbes found in the birth canal that newborns are exposed to during a vaginal birth. We suspect that these microbes may benefit a child’s health, including enhancing metabolism and training the immune system,” lead study author Noel Mueller, PhD, MPH, an assistant professor of epidemiology at Johns Hopkins University, said in a press release.2

“We need more studies to determine whether exposing Cesarean-delivered newborns to vaginal microbes at birth can reduce their future risk of metabolic disorders such as obesity.”

Disclosures: The researchers report no financial disclosures.

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  1. Mueller NT, Mao G, Bennet W, et al. Presentation 152. Can vaginal delivery reduce the intergenerational transmission of overweight and obesity? Findings from the Boston Birth Cohort. Presented at: American Heart Association’s Scientific Sessions 2016; November 12-16, 2016; New Orleans, LA.
  2. Children born by Cesarean section may have a greater risk of obesity [press release]. Dallas, TX: American Heart Association/American Stroke Association Newsroom; November 13, 2016. Accessed November 18, 2016.