PhD A.J. (Anna) Suleri

Below is a brief summary of the dissertation:

Early childhood psychiatric disorders are becoming more prevalent, highlighting the need to understand the biological factors that contribute to these conditions. One critical period for child health is pregnancy, when environmental stressors can have lasting effects on neurodevelopment and disease susceptibility. This thesis explores the role of maternal immune activation – triggered by infections or inflammation during pregnancy – as a potential pathway linking prenatal risk factors to psychiatric outcomes in children. Using data from two large cohorts, the Generation R Study (Netherlands) and ALSPAC (UK), this thesis investigates three main areas: the relationship between maternal immune activation and child psychiatric symptoms, brain development, and the potential of epigenetic markers.

This research found that prenatal infections were linked to emotional and behavioral problems in adolescence, with this association beginning as early as 1.5 years of age and continuing into adolescence. However, these infections did not seem to link directly to autistic traits. Brain imaging studies revealed that prenatal infections affected brain development, with subtle changes in the frontal and temporal lobes. Surprisingly, maternal inflammation showed fewer associations with brain structure and function. Lastly, this thesis examined epigenetic markers as an alternative way to capture the impact of maternal immune activation. While DNA methylation in newborns was weakly linked to prenatal infections, it did not predict later health outcomes.

Together, these findings suggest that infection may be a more significant factor than inflammation in shaping child neurodevelopment and underscore the importance of refining how we measure maternal immune activation in research and clinical practice.