The association between preterm delivery and autism spectrum disorder in childhood: A retrospective cohort study

Background

Prematurity complications are a leading cause of mortality and morbidity in offspring, including adverse neurodevelopmental outcomes. The association between preterm birth (PTB) and autism spectrum disorder (ASD) remains debated.

Objective

To investigate the association between PTB and ASD diagnosis during childhood.

Methods

This cohort study analyzed data from community clinics and a tertiary hospital, encompassing deliveries from 2005 to 2017. ASD incidence was compared across gestational age categories: extremely preterm (<28 weeks), very preterm (28–32 weeks), moderate to late preterm (32–37 weeks), and term (≥37 weeks). Additional comparisons were made between all preterm (<37 weeks) and term deliveries (≥37 weeks). Cumulative ASD incidence was assessed using Kaplan–Meier survival curves and a Cox proportional hazards model adjusted for potential confounders.

Results

Among 114 975 pregnancies, 0.3% delivered at <28 weeks, 0.6% at 28–32 weeks, and 6% at 32–37 weeks, with 6.9% preterm deliveries overall. Univariable analysis revealed a significant association between PTB and ASD (1.6% for <28 weeks vs 0.3% for 28–32 weeks vs 0.8% for 32–37 weeks vs 0.7% for term, P = 0.036). Crude ASD incidence was 0.8% (odds ratio [OR] 1.21, 95% confidence interval [CI] 0.93–1.56, P = 0.15). However, adjusted results showed no significant association: adjusted hazard ratio = 0.74 (95% CI 0.24–2.34, P = 0.61) for <28 weeks, 0.99 (95% CI 0.24–3.99, P = 0.98) for 28–32 weeks, and 1.07 (95% CI 0.81–1.43, P = 0.63) for 32–37 weeks. Kaplan–Meier analysis showed similar cumulative ASD incidence across groups (P = 0.855).

Conclusion

This retrospective cohort study found no significant association between PTB and childhood ASD diagnosis.