Study subjects were the offspring of women who underwent a 3-hour oral glucose tolerance test between 27 and 31 weeks’ gestation, and childhood outcomes were assessed between the ages of 5 and 10 years.
Prior to the widespread recognition of the concept of fetal programming over 3 decades ago, Dr. Norbert Freinkel proposed that mild forms of diabetes, such as GDM, might exaggerate the normal dependency of the fetus on maternal fuels and that the concept of teratogenesis should be expanded to include alterations which could have long-range effects on behavioral, anthropometric, and metabolic functions, Dr. Landon said.
Multiple subsequent studies have demonstrated a link between in utero exposure to maternal hyperglycemia and the development of obesity in childhood – findings that are independent of both birth weight and maternal obesity.
A 2013 study showed that GDM was associated with both overweight status in childhood and childhood obesity (Diabet. Med. 2013;30:1449-56). Also, the landmark Hyperglycemia and Adverse Pregnancy Outcomes study showed that with increasing maternal glucose levels lower than the threshold for GDM diagnosis, the frequency of large-for-gestational-age infants increased proportionately – and this risk also remained after adjustment for maternal BMI and other confounders (N. Engl. J. Med. 2008;358:1991-2002).
“We have similarly reported a monotonic relationship between maternal glucose levels and the frequency of large-for-gestational-age infants in a secondary analysis from the Mild GDM Network randomized controlled trial. Recognizing that maternal glycemia clearly contributes to fetal growth, we sought to determine in this analysis whether the degree of maternal glucose tolerance during pregnancy affects the risk of childhood obesity and metabolic dysfunction,” Dr. Landon said.
Although the findings do not address the potential long-term effects of more significant hyperglycemia during pregnancy, they do confirm that maternal obesity has a greater impact on childhood obesity risk than exposure to mild hyperglycemia during pregnancy, he said in an interview.
Dr. Landon reported having no financial disclosures.