Infants delivered via cesarean section have about twice the risk of becoming obese as infants delivered vaginally, according to a new study published in the journal Archives of Disease in Childhood.

Researchers recruited more than 1,250 pregnant women from the Boston area and followed their children until the age of 3. They found that at 3 years old, 15.7 percent of children delivered by C-section were already obese, while only 7.5 percent of children delivered vaginally were obese.

Dr. Susanna Huh, lead author and an assistant professor of medicine at Harvard Medical School, said the findings still need to be confirmed in later studies, but they suggest that women considering having a C-section that isn't medically necessary should know that their children may be at higher risk for obesity.

"Almost one in three children are delivered by C-section in the U.S., and if cesarean delivery is a risk factor for obesity, this would be an important reason to avoid them if they aren 't necessary," Huh said.

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