Children may be two times more likely to be obese if they were born via caesarean section, say researchers.

In the United States, around 1 in 3 babies are delivered by caesarean section, and this method of delivery has already been linked to an increased risk of subsequent childhood asthma and allergic rhinitis. The study is published in the Archives of Disease in Childhood.

Findings of the study are based on 1,255 mother and child pairs, who between 1999 and 2002, attended 8 outpatient maternity services in eastern Massachusetts, USA.

The mothers participated in the study before 22 weeks of pregnancy, and their babies were measured and weighed at birth, 6 months, and at 3 years of age. In addition, the researchers measured body fat.

284 (22.6%) of the 1,255 babies were born via caesarean section and 971 (77.4%) were born vaginally.

Compared to women who delivered vaginally, mothers who delivered by c-section tended to:

  • weigh more
  • breastfeed their babies for a shorter duration
  • deliver heavier infants

The researchers found that children delivered via c-section were two times more likely to be obese by age 3, than those delivered vaginally – (16% vs. 7.5%, respectively).

In addition, children born via c-section had higher BMI and body fat measurements by three years of age.

According to the researchers, one reason may be due to the difference in the composition of gut bacteria acquired at birth between the two delivery methods.

Earlier studies have demonstrated that children born via caesarean section have more Firmicutes bacteria and less Bacteroides bacteria in their guts. In addition, other studies have indicated that obese people have higher levels of Firmicutes bacteria.

The researchers say that bacteria in the gut may encourage the development of obesity by increasing energy extracted from the diet, and by activating cells to increase insulin resistance, fat deposits, and inflammation.

They write:

“An association between caesarean birth and increased risk of childhood obesity would provide an important rationale to avoid non-medically indicated caesarean section.”

The authors highlight that mothers who choose to deliver via c-section should be informed about the potential health risks to her baby, including the chances of obesity.

Written By Grace Rattue