OBJECTIVE Gestational diabetes mellitus has been associated with offspring cardiac congenital malformations, ventricular hypertrophy, and diastolic dysfunction in large observational cohort studies... Show moreOBJECTIVE Gestational diabetes mellitus has been associated with offspring cardiac congenital malformations, ventricular hypertrophy, and diastolic dysfunction in large observational cohort studies and experimental animal models. We assessed the associations of maternal random glucose concentrations across the full range with childhood cardiac ventricular structure and function. RESEARCH DESIGN AND METHODS In a population-based prospective cohort among 1,959 women and their offspring, maternal random glucose concentrations were measured at a median 13.1 weeks' gestation (95% range 10.5-16.8 weeks). We obtained offspring cardiac outcomes, relative to body size, through cardiac MRI at 10 years. RESULTS The mean maternal random glucose concentration was 4.4 mmol/L (SD 0.8). The highest quintile of maternal glucose concentrations, compared with the lowest quintile, was associated with a lower childhood left ventricular mass (-0.19 SD score [SDS]; 95% CI -0.31, -0.07) and left ventricular end-diastolic volume (-0.17 SDS; 95% -0.28, -0.05). Also, higher maternal glucose concentrations across the full range per 1 mmol/L increase were associated with a lower childhood left ventricular mass and left ventricular end-diastolic volume (Pvalues <= 0.05). Adjustment for maternal prepregnancy BMI, gestational age, and weight at birth or childhood BMI and blood pressure did not influence the effect estimates. Maternal glucose concentrations were not significantly associated with childhood right ventricular end-diastolic volume or left and right ventricular ejection fraction. CONCLUSIONS Higher maternal random glucose concentrations in the first half of pregnancy are associated with a lower childhood left ventricular mass and left ventricular end-diastolic volume, with the strongest associations for childhood left ventricular mass. These associations were not explained by maternal, birth, or childhood characteristics. Further studies are needed to replicate these findings using repeated maternal glucose measurements throughout pregnancy and offspring cardiac outcomes throughout childhood and adulthood. Show less