The rates of both cesarean sections and childhood obesity have risen steadily in the U.S. over the last couple of decades. Now, a surprising new study suggests the two trends may be linked.
After following 1,255 mother-and-baby pairs from pregnancy through the child's third birthday, Harvard researchers found that by age 3, 16 percent of children born by C-section were obese, about twice as many as those delivered vaginally.
Moms who had a C-section tended to weigh more and give birth to heavier babies than those who delivered vaginally, and also breastfed for a shorter period of time. But the connection between C-sections and obesity persisted even after adjusting for those factors. The researchers speculate that the type of gut bacteria acquired during vaginal birth could protect infants from turning into tubby toddlers.
Previous studies have found that C-section babies have more of the type of bacteria found in obese adults. Research in animals and humans suggests that bacterial imbalance might cause the body to extract more calories from food and stimulate cells to boost insulin resistance, inflammation, and fat deposits.
Other research has identified C-section delivery as a risk factor for asthma and allergies in childhood. Although far from definitive, this latest study adds one more reason to avoid a C-section unless it's medically necessary.
Currently in the U.S., one of out three babies enters the world through a surgical delivery, far too many according to experts. That's why unnecessary C-sections make our list of What to reject when you're expecting. Our comprehensive report also provides advice on ways to ensure the best possible pregnancy and delivery.
Delivery by caesarean section and risk of obesity in preschool age children: a prospective cohort study [Archives of Diseases in Children]