Effect of gestational age on cerebral lesions in neonatal encephalopathy

To determine the risk on brain lesions according to gestational age (GA) in neonates with neonatal encephalopathy.

Secondary analysis of the prospective national French population-based cohort, Long-Term Outcome of NeonataL EncePhALopathy.

French neonatal intensive care units.

Neonates with moderate or severe neonatal encephalopathy (NE) born at ≥34 weeks' GA (wGA) between September 2015 and March 2017.

The results of MRI performed within the first 12 days were classified in seven injured brain regions: basal ganglia and thalami, white matter (WM), cortex, posterior limb internal capsule, corpus callosum, brainstem and cerebellum. A given infant could have several brain structures affected. Risk of brain lesion according to GA was estimated by crude and adjusted ORs (aOR).

MRI was available for 626 (78.8%) of the 794 included infants with NE. WM lesions predominated in preterm compared with term infants. Compared with 39-40 wGA neonates, those born at 34-35 wGA and 37-38 wGA had greater risk of WM lesions after adjusting for perinatal factors (aOR 4.0, 95% CI (1.5 to 10.7) and ORa 2.0, 95% CI (1.1 to 3.5), respectively).

WM is the main brain structure affected in late-preterm and early-term infants with NE, with fewer WM lesions as GA increases. This finding could help clinicians to estimate prognosis and improve the understanding of the pathophysiology of NE.

NCT02676063, ClinicalTrials.gov.