February 27, 2014
Caesarian Births Linked To Increased Risk Of Childhood Obesity
Brett Smith for redOrbit.com - Your Universe Online
While a caesarian section may be a life-saving operation for a mother, the artificial mode of birthing could increase the risk of the child becoming overweight later in life.
According to a new study from the Imperial College London and published in the journal PLOS ONE, the chance of being overweight or obese increases 26 percent for a child when it is born by caesarean section compared to vaginal delivery.
"There are good reasons why C-section may be the best option for many mothers and their babies, and C-sections can on occasion be life-saving,” said study author Neena Modi, a professor of neonatal medicine at ICL. “However, we need to understand the long-term outcomes in order to provide the best advice to women who are considering caesarean delivery.”
"This study shows that babies born by C-section are more likely to be overweight or obese later in life,” she added. “We now need to determine whether this is the result of the C-section, or if other reasons explain the association."
To reach their conclusion, the study researchers considered 40 studies published before March 31, 2012, which included data on over 160,000 individuals. They discovered that the average body mass index (BMI) of adults born by caesarean section is around half a unit more than those born by vaginal delivery.
When the researchers were able to demonstrate a connection, they pointed out that they did not find a cause-and-effect relationship between being delivered by caesarian section and being overweight.
"There are plausible mechanisms by which caesarean delivery might influence later body weight,” said study author Matthew Hyde, a neonatal researcher at ICL. “The types of healthy bacteria in the gut differ in babies born by caesarean and vaginal delivery, which can have broad effects on health. Also, the compression of the baby during vaginal birth appears to influence which genes are switched on, and this could have a long-term effect on metabolism."
The new study comes after two large medical groups representing America's obstetricians/gynecologists issued joint guidelines that included language designed to reduce caesarian sections. The guidelines extended the length of time a woman could be allowed to be in labor, effectively lowering the odds she will need a caesarian section.
“Evidence now shows that labor actually progresses slower than we thought in the past, so many women might just need a little more time to labor and deliver vaginally instead of moving to a cesarean delivery,” said Dr. Aaron B. Caughey, a member of the American College of Obstetricians and Gynecologists who helped develop the new guidelines. “Most women who have had a cesarean with their first baby end up having repeat cesarean deliveries for subsequent babies, and this is what we’re trying to avoid. By preventing the first cesarean delivery, we should be able to reduce the nation’s overall cesarean delivery rate.”
According to a statement from the ACOG, a third of American women gave birth via cesarean section in 2011, a 60 percent increase since 1996.