Around 33% of births in the U.S. are cesarean births, according to the U.S. Centers for Disease Control and Prevention, and the rate of c-sections is rising.
The study, led Dr. Jan Blustein, Ph.D., M.D., from the New York University of Medicine, analyzed data on a total of 10,219 British born children between 1991 and 1992.
Dr Blustein said that "there may be long-term consequences to children that we don't know about" associated with C-sections.
In fact, there have already been health risks linked to C-sections. One study revealed that C-section babies are five times more likely to develop allergies by age two than those born naturally.
Another study demonstrated that babies born by c-section are more likely to have asthma than babies delivered vaginally.
The aim of the study, which was published in the International Journal of Obesity, was "to assess associations of Cesarean section with body mass from birth through adolescence."
C-section babies weigh less than others at first, then more later onOn average, children born via C-section were 0.125 pounds lighter than those vaginally born.
The children were analyzed by the researchers at various points in their lives to evaluate their body mass.
By the time the babies were six weeks old, those who were delivered via C-section were already heavier than the others. This trend was consistent at the age of three, eleven, and fifteen years.
At the age of 11, those who were delivered by C-section were found to be 83 percent more likely to be overweight than those born vaginally.
The results were adjusted to account for factors such as mother's weight and whether they were breastfed.
Blustein wasn't able to confirm compellingly whether C-section deliveries are the major cause behind this trend. However, she said that if they are, it is likely due to the fact that unlike vaginally delivered babies, C-section babies aren't exposed to important bacteria during birth.
However, Blustein added:
"The other possibilities are (that) these are children that would have been heavier anyway. Being heavy as a woman is a risk factor for C-section, so that's the problem with trying to figure out whether this is real or if it's simply a matter of selection."
The findings of this study are in line with a similar study carried out at the Children's Hospital Boston, which suggested that C-Section can potentially double childhood obesity risk.
A report from Trust for America's Health and the Robert Wood Johnson Foundation showed that obesity rates in the USA are holding steady for the first time in three decades.