Previous studies suggest that fetal programming to hyperglycemia in pregnancy is due to modulation of DNA methylation (DNAm), but they have been limited in their maternal glycemic characterization. In Gen3G, we used a principal component analysis to integrate multiple glucose and insulin values measured during the second trimester oral glucose tolerance test. We investigated associations between principal components and cord blood DNAm levels in an epigenome-wide analysis among 430 mother-child pairs. The first principal component was robustly associated with lower DNAm at cg26974062 (; p = 9.9 × 10) in cord blood. is a well-known DNAm marker for type 2 diabetes in adults. We hypothesize that abnormal glucose metabolism in pregnancy may program dysregulation of across the life course.