Women born by cesarean section are at increased risk for Type 2 diabetes, according to a new study.
The report, in JAMA Network Open, included 33,226 women born between 1946 and 1964, and followed for up to 25 years. More than a third were obese, and 6 percent had a diagnosis of Type 2 diabetes.
Compared with women born vaginally, those born by C-section had an 11 percent increased relative risk for obesity and a 46 percent increased risk for diabetes.
Obesity is the largest risk factor for diabetes, and the lead author, Dr. Jorge E. Chavarro, an associate professor of nutrition at Harvard, said that initially he expected that if there was an association, it would be a result of obesity. But even after controlling for their body mass index, women born by C-section had a 34 percent increased relative risk for diabetes. This suggests that cesarean section itself increases the risk for diabetes, independent of the increase in risk caused by obesity.
“The relative increase in risk is fairly modest,” said Dr. Chavarro, “and this is not to say that C-sections shouldn’t happen. But there are many performed without any medical indication. This study adds evidence that performing C-sections without a medical reason is harmful — and that the effect can appear even decades later.”