Babies who are exposed to mom’s diabetes and obesity while in the womb are at increased risk of developing type 2 diabetes in adolescence, according to new research.

To prevent “youth-onset” type 2 diabetes, “we may need to take a life course approach, targeting, in addition to childhood obesity, the increasing number of women with pregnancies complicated by obesity and diabetes,” researchers conclude.

Dr. Dana Dabelea at the University of Colorado Denver and co-investigators studied 79 youths who were diagnosed with type 2 diabetes before their 20th birthday and 190 nondiabetic control youths.

They found that far more diabetic youth than nondiabetic youth were exposed to mom’s diabetes in the womb (roughly 30 percent versus 6 percent). The same was true for overweight and obesity, with 57 percent of diabetic youth versus 27 percent of nondiabetic youth being exposed to maternal overweight/obesity.

The adjusted odds for type 2 diabetes was roughly 7-fold higher with exposure to maternal diabetes and more than 3-fold higher with exposure to maternal overweight/obesity.

Dabelea and colleagues estimate that 47 percent of youth-onset type 2 diabetes can be attributed to prenatal (before birth) exposure to maternal diabetes and obesity.

Moreover, “the odds for type 2 diabetes was 2.5-fold higher when the diabetes was diagnosed before versus after pregnancy,” Dabelea’s team reports in the journal Diabetes Care. “This finding suggests that even in the selected group of offspring at high genetic risk, exposure to diabetes in utero is associated with a further increase in type 2 diabetes risk.”

The association between offspring diabetes and maternal obesity was attenuated after accounting for childhood BMI, indicating, the researchers say, that maternal obesity increases the probability of childhood obesity, which in turn heightens the risk of diabetes.

SOURCE: Diabetes Care, July 2008.