Maternal Gestational Diabetes Mellitus (GDM) Moderates the Association Between Birth Weight and EEG Power in Healthy Term-Age Newborns.

Gestational diabetes mellitus (GDM) affects around 10% of pregnancies in the United States and has been linked to neurodevelopmental sequelae in children. However, there is a paucity of studies investigating early-life neural markers in GDM-exposed infants. This study examined the association of GDM with relative EEG power among healthy term-age neonates collected during natural sleep. Participants included a diverse cohort of 101 mothers (45% multiracial, 25% Black, and 69% Hispanic or Latina) and their infants (gestational age at birth M_age = 39.0 ± 0.95; 46.5% female). We did not observe the main effect of GDM on infant relative EEG power. Our post hoc analyses revealed a significant interaction effect between GDM and infant birth weight on relative EEG power in active sleep. Among GDM-exposed neonates, increased birth weight was associated with increased relative theta EEG power and decreased relative beta and gamma EEG power across multiple electrode regions. Among non-GDM-exposed infants, increased birth weight was associated with decreased relative theta EEG power and increased relative beta and gamma EEG power across multiple electrode regions. Our findings suggest that alterations in fetal growth may serve as either an indirect marker or pathway through which GDM influences the developing fetal brain.