Background The longitudinal trajectory of body mass index (BMI) and brain structure development during peri-adolescence is not clearly defined in offspring prenatally exposed to gestational diabetes mellitus (GDM) vs. un-exposed offspring.

Methods Participants between age 9 and 10 years (N=9,583) were included from the Adolescent Brain and Cognitive Development (ABCD) Study and followed yearly though 4-year follow-up. GDM and puberty status were self-reported. BMI was calculated yearly, and MRI assessed brain structure biennially. Mixed-effects models analyzed trajectories of BMI and brain structural measures between groups controlling for sociodemographic covariates, and linear spline was defined with a knot at onset of puberty.

Results There was an interaction of exposure by age in change in BMI [β (95% CI) = 0.032 (0.008, 0.056), P=0.009] and mean cortical thickness [β (95% CI) = −0.038 (−0.071, −0.004), P=0.027]. The former was driven by greater pre-pubertal increases in BMI [β (95% CI) = 0.051 (0.002, 0.100), P=0.043], whereas the latter was driven by faster post-pubertal declines in cortical thickness among GDM-exposed offspring [β (95% CI) = −0.051 (−0.095, −0.007), P=0.046].

Conclusion Prenatal GDM exposure is associated with greater pre-pubertal increases in BMI and faster post-pubertal cortical thinning in youth age between 9 and 15.

Practitioner Points

– Prenatal GDM exposure is associated with greater pre-pubertal increases in BMI and faster post-pubertal cortical thinning in youth age between 9 and 15.

– It is important to recognize puberty as a window of vulnerability for altered brain development among youth prenatally exposed to GDM.

The authors have declared no competing interest.

National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases R01DK137899 (PI: SL), K01DK115638 (PI: SL), R03DK129186 (PI: SL)

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