Clinical associations and time of onset of cerebral white matter damage in very preterm babies.

Neuropathological examinations were carried out at necropsy on 83 very pre-term babies who died during their first hospital admission. Forty seven (57%) babies had evidence of cerebral damage-39 with ischaemic white matter damage. The time of onset of ischaemic lesions was thought to be prenatal in 12 cases (31%) and postnatal in a further 12 (31%). The exact timing of damage could not be determined in 15 (38%) cases. Maternal and neonatal case notes were reviewed to ascertain clinical associations of ischaemic white matter damage. There were no clear associations between adverse clinical factors and prenatal ischaemic white matter damage. In contrast, pre-eclampsia, intrauterine growth retardation, and delivery without labour were associated with postnatal damage as were neonatal sepsis, necrotising enterocolitis, and seizures. The absence of a clear association between the timing of adverse clinical factors and the timing of ischaemic cerebral damage suggests that cerebral damage in very preterm babies may result from a sequence of events rather than one specific insult.