Prediabetes predicts a 50% cumulative incidence of type 2 diabetes within 5 years in nonpregnant patients, but much less is known about the condition in pregnant women, she added, noting that recent studies suggest a threefold increased risk for gestational diabetes in the second trimester – and perhaps even greater risk in obese women – among those with prediabetes.
The addition of HbA1C to the prenatal panel in California, along with a recommendation that those with prediabetes be diagnosed with and treated for gestational diabetes, provided the opportunity to evaluate whether such treatment affected the incidence of gestational diabetes as compared with usual care, she noted.
“We hypothesized that treatment would lower the risk of GDM, especially among obese women,” she said.
Though limited by the sample size and the fact that providers were not blinded to patients’ treatment group, the randomized, controlled study design is a strength, and the findings add to the limited data on HbA1C in pregnancy and the management of prediabetes in pregnant patients, she said.
The study was underpowered to determine whether early treatment reduces the risk of GDM in women with prediabetes, but the findings suggest that such treatment may reduce the risk among nonobese women.
“While this finding is unexpected, we think the findings are consistent with literature suggesting that women with prepregnancy obesity remain at higher risk of adverse perinatal outcomes even in absence of GDM or excessive weight gain. We hypothesize that any small effect may be attenuated by the morbidity associated with prepregnancy adiposity. Larger studies powered to examine the primary outcomes and perinatal outcomes are required,” she concluded.
This study was funded by the American College of Obstetricians and Gynecologists Abbott Nutrition Research Fellowship, the Stanford Child Health Institute, and the Valley Foundation for the California Institute of Medical Research. Dr. Osmundson reported having no disclosures.