Academic Performance in Adolescents Born to Mothers With Gestational Diabetes-A National Danish Cohort Study

Context: The prevalence of gestational diabetes mellitus (GDM) is increasing, and intrauterine hyperglycemia is suspected to affect offspring cognitive function. Objective: We assessed academic performance by grade point average (GPA) in children aged 15 to 16 years at compulsory school graduation, comparing offspring exposed to GDM (O-GDM) with offspring from the background population (O-BP). Methods: This register-based, cohort study comprised all singletons born in Denmark between 1994 and 2001 (O-GDM: n=4286; O-BP: n=501045). Standardized and internationally comparable GPAs were compared in univariate and multivariable linear models. Main outcome measures included the adjusted mean difference in GPA. We also analyzed the probability of having a high GPA, a GPA below passing, and no GPA registered. Results: O-GDM had a GPA of 6.29 (SD 2.52), whereas O-BP had a GPA of 6.78 (SD 2.50). The adjusted mean difference was -0.36 (95% CI, -0.44 to -0.29), corresponding to a Cohen's D of 0.14. O-GDM had a lower probability of obtaining a high GPA (adjusted odds ratio [aOR] 0.68; 95% CI, 0.59 to 0.79), while their risk of obtaining a GPA below passing was similar to O-BP (aOR 1.20; 95% CI, 0.96 to 1.50). O-GDM had a higher risk of not having a GPA registered (aOR 1.38; 95% CI, 1.24 to 1.53). Conclusion: Academic performance in O-GDM was marginally lower than in O-BP. However, this difference is unlikely to be of clinical importance.