University of North Carolina at Chapel Hill Graduate School
Doi
Abstract
The prevalence of autism spectrum disorder (ASD) has increased, and ASD causes substantial burden for individuals and their families. The prevalence of cognitive impairment also increased in children. ASD and cognitive function are neurodevelopmental disorders with multiple factors involved; however, specific risk factors remain unclear. Previous studies have shown associations between cesarean delivery and neurodevelopmental disorders; and limited studies focused on malpresentation at delivery, a common indication for cesarean delivery, and its association with ASD or cognitive function. The studies are limited by inconclusive results, by using outcome measurements with limited validity, or by not accounting for the gestational age-dependency prevalence of malpresentation. To address these limitations, this study utilized data from the Study to Explore Early Development, a case-control study conducted in the United States. In Aim 1, we identified malpresentation and evaluated the association between malpresentation at delivery and ASD. In Aim 2, we evaluated the association between malpresentation and cognitive function in ASD and children from the general sample separately. In our study, we included 1371 children with ASD and 1576 population controls for Aim 1; and 1368 children with ASD and 1576 children from the general sample for Aim 2. We assessed whether the observed associations were modified by maternal pre-pregnancy body mass index (BMI) and gestational age. In Aim 1, we found an association between malpresentation and ASD (ORa=1.36, 95% CI: 1.06, 1.74), after adjustment for maternal age, poverty level, maternal hypertensive disorder, and maternal smoking. The association was similar for other malpresentations and breech. We did not find the association was modified by gestational age or pre-pregnancy BMI. We did not have evidence that malpresentation was associated with below average cognitive function, either in the ASD or the children from the general sample. Our findings suggest that malpresentation is associated with ASD, but may not be associated with cognitive function. Future well-powered studies should investigate the role of gestational age or pre-pregnancy BMI in these associations. These results can help identify children at higher risk of ASD for whom developmental screening at younger ages may allow for early identification and potentially earlier intervention.Doctor of Philosoph
