Brumbaugh JE, et al. - Using the 1994-2000 Olmsted County Birth Cohort, researchers conducted this population-based cohort study to determine how gestational age relates to research-identified autism spectrum disorder (ASD-R) in the context of perinatal risk factors. Included children were born and lived in Olmsted County after age 3. To identify connections between perinatal characteristics and ASD-R, Cox proportional hazards models were fit. Data reported that preterm birth (< 37 weeks' gestation) incidence was 8.6% among 7,876 children. At age 21, ASD-R's cumulative incidence was 3.8%. Among children with maternal history available (N = 6,851), a maternal psychiatric disorder was linked to ASD-R. Increased risk of ASD-R among children born preterm was attenuated by infant and maternal characteristics in comparison to children born full term.