Maternal Diabetes and Early Neurodevelopment: Differential Milestone Attainment in Offspring by Diabetes Type

OBJECTIVE: Maternal diabetes increases offspring risk for neurodevelopmental disorders, but its association with delayed developmental milestones is unknown. We examined milestone attainment in offspring of mothers with gestational diabetes mellitus (GDM) and pregestational type 1 and type 2 diabetes compared with unexposed control individuals. RESEARCH DESIGN AND METHODS: We examined a nationwide retrospective cohort study of 466,462 term singleton infants born January 2018 to December 2021 using linked national maternal-child health clinic and hospital discharge data. Developmental data were obtained from nurse-administered structured assessments at routine well-child visits through 24 months of age. Adjusted hazard ratios (aHRs) and 95% CIs for failure to attain developmental milestones were estimated by diabetes type and infant sex. RESULTS: Pregestational diabetes was associated with increased risk for delayed milestone attainment in language, personal-social, and gross motor domains compared with control groups. Offspring of mothers with type 1 diabetes showed the highest risk, followed by those with type 2 diabetes. The association between type 1 diabetes and developmental delay was primarily driven by female offspring, with elevated risks in personal-social (aHR, 1.64; 95% CI, 1.14-2.36), language (aHR, 1.44; 95% CI, 1.09-1.89), and gross motor (aHR, 1.41; 95% CI, 1.05-1.89) domains. GDM was associated with modestly increased risk limited to the fine motor domain (aHR, 1.11; 95% CI, 1.06-1.16). CONCLUSIONS: Pregestational diabetes is associated with delayed milestone attainment, with risk varying by diabetes type, developmental domain, and infant sex. Further research should explore long-term trajectories to inform early intervention for children exposed to maternal diabetes.