WASHINGTON – Babies born by Caesarean section are twice as likely to be obese by age three as infants delivered vaginally, according to a new study published Thursday in the Archives of Disease in Childhood journal.
The study included more than 1,250 mother-child pairs admitted to Massachusetts hospitals between 1999 and 2002. All of the mothers joined the study before 22 weeks into their pregnancy, and 25 percent of babies were delivered by C-section. The rest were delivered vaginally.
Babies were measured and weighed at birth, at 6 months and again at age three.
Average birth weight was not statistically higher for babies born by C-section. But nearly 16 percent of children delivered via C-section were obese by the age of three, compared with 7.5 percent of those born vaginally. Also, about 19 percent of the C- section kids were overweight compared to just less than 17 percent of the others.
Those children delivered by C-section also had higher skinfold thickness (a measure of body fat) at age 3, the study showed.
The researchers said their findings held even after they compensated for factors known to increase the risk of childhood obesity, including overweight mothers and high birth weight.
Differences in gut bacteria between newborns delivered by C- section and those born vaginally could be behind the weight gain, the researchers suggested. Previous research has shown that children born by C-section have larger amounts of Firmicutes bacteria — which also is generally found in higher levels in obese adults.
Gut bacteria influence the development of obesity by increasing energy extracted from food, and by stimulating cells to boost insulin resistance, inflammation and fat deposits, the authors suggested.
In the United States today, about one in three babies is born via C-section, and one in three kids is overweight or obese. (Xinhua)