Fetal Head Growth in Children with Autistic Traits and Autism Spectrum Disorder
Objectives: The objective of the current study is to prospectively evaluate prenatal head growth in children from the general population that later develop autistic traits. A second objective is to compare prenatal head growth between children with clinically diagnosed ASD and typically developing children.
Methods: This study included over 5,700 children participating in two large longitudinal prenatal cohorts, including more than 80 children with a confirmed diagnosis of ASD. Fetal head circumference (HC) was measured repeatedly during pregnancy using ultrasound. Autistic traits were measured with the Social Responsiveness Scale and the Autism Quotient. A diagnosis of ASD was based on mother report and confirmed with medical records. Additionally, ultrasounds were retrospectively collected for 45 children with ASD at a clinical research center. Longitudinal HC measurements at three time points were analyzed using a Latent Growth curve model approach to assess the relation of prenatal growth on autistic traits measured later in life.
Results: Preliminary analyses suggested an inverse relationship between prenatal head growth and autistic traits later in life. Children with more autistic traits showed HC growth curves that were characterized by smaller slopes and intercepts.
Conclusions: To our knowledge, this is the first large population-based study looking into prenatal brain growth and autistic traits. Preliminary results suggest that atypical brain growth in ASD may start in utero. Additional analyses comparing prenatal head growth between children with clinically diagnosed ASD and typically developing children will be conducted.