School performance of preterm-born children after intraventricular hemorrhage

Importance: Intraventricular hemorrhage (IVH) is a significant complication of preterm birth, affecting approximately 20% of preterm infants. Despite its prevalence, the effect of IVH beyond the impact of prematurity alone has been scarcely studied beyond early childhood, posing an important knowledge gap.

Objective: To investigate the association of IVH with national school performance throughout childhood to adolescence.

Design, Setting, and Participants: This population-based cohort study included all very preterm infants (<32 weeks' gestation) and full-term infants (≥37 weeks' gestation) born in New South Wales, Australia, between January 1, 2007, and December 31, 2013. Cohorts were very preterm children with low-grade (grades 1-2) or high-grade (grades 3-4) IVH, very preterm controls without IVH, and full-term controls. Analyses were conducted from January 30 to September 18, 2024.

Exposure: IVH grade 1 to 4.

Main Outcomes and Measures: The primary outcome was overall performance on standardized national school assessments at age 8 to 9, 10 to 11, and 12 to 13 years, including adjusted mean differences (AMDs) in z scores between children with IVH and very preterm controls. Secondary outcomes were domain-specific performance in reading, writing, spelling, grammar, and numeracy and whether children met the national minimum standards overall and for each domain. Academic trajectories were also compared by group.

Results: This study included 408 189 children: 557 with low-grade IVH, 85 with high-grade IVH, 2557 very preterm controls without IVH, and 404 990 full-term controls. Children with low-grade IVH performed similarly to preterm controls at age 8 to 9 years (AMD in overall academic z score, -0.06; 95% CI, -0.14 to 0.03), 10 to 11 years (AMD, -0.09; 95% CI, -0.21 to 0.03), and 12 to 13 years (AMD, -0.04; 95% CI, -0.24 to 0.16). Children with grade 2 IVH (n = 145), however, performed significantly worse than very preterm controls at age 8 to 9 years (AMD, -0.20; 95% CI, -0.36 to -0.04). Children with high-grade IVH performed significantly worse than very preterm controls at age 8 to 9 years (AMD, -0.50; 95% CI, -0.71 to -0.30), 10 to 11 years (AMD, -0.59; 95% CI, -0.85 to -0.34), and 12 to 13 years (AMD, -0.61; 95% CI, -1.05 to -0.17). Numeracy was a consistently weak domain for children with high-grade IVH throughout school age (eg, at age 8 to 9 years, AMD in the numeracy z score compared with very preterm controls was -0.49 [95% CI, -0.70 to -0.28]). Differences in academic trajectories between groups remained fixed with increasing age; however, all groups showed improvement over time (eg, adjusted β for very preterm children, 32.3 [95% CI, 31.2-33.5]; children with low-grade IVH, 31.5 [95% CI, 29.0-34.0]; high-grade IVH, 30.2 [95% CI, 24.1-36.4]).

Conclusions and Relevance: In this cohort study, the association of low-grade IVH with worse school performance appeared limited to children with grade 2 IVH. Children with high-grade IVH consistently showed poorer academic performance into adolescence than their peers born very preterm without IVH. Nevertheless, very preterm children, regardless of IVH grade, demonstrated academic progress over time, underscoring the need for ongoing educational support to help them to realize their full potential.