A new study which included more than 38,000 people from 10 different countries found that children delivered via Cesarean section may have an increased risk of being obese later in life.
This study was published February 26, 2014 in the journal PLOS ONE. It is the largest study yet which to find a link between Caesarean delivery and increased weight in adulthood.
The researchers found that the babies delivered vaginally were less likely to be obese as adults. Babies delivered by C-section were found to have a 22 percent higher risk of being obese as adults. C-section babies also have a 26 percent higher chance of being overweight than babies born via vaginal delivery.
This study is not the first one to link Cesearean section births to higher obesity rates. In 2012, a smaller study of children in Massachusetts found that babies born by C-section had double the risk of being obese by 3 years of age.
Researchers on this new study reviewed 15 other previous studies which collected information from individuals on the delivery method of their birth and their body mass index (BMI), which measures body fat, in adulthood. Participants ranged in age from 18-70 years old.
"Obese" was defined as having a BMI over 30 and "overweight" as a BMI between 25 and 30.
According to Dr. Neena Modi, a study researcher from Imperial College London, people need to know that C-section births should not necessarily be avoided if they are medically necessary. Modi said that there can be many good reasons why a C-section delivery may be the best option for some mothers.
"C-sections can on occasion be life-saving," said Modi in a statement. "However, we need to understand the long-term outcomes in order to provide the best advice to women who are considering Caesarean delivery."
It is important to note that this study does not prove that there is a true cause-and-effect relationship between Cesearean deliveries and obesity.
Though nothing has been concluded, some researchers believe there is a gut bacteria that may explain this relationship. The types of bacteria in the gut of babies born vaginally or by C-section differ.