Neuroimaging Findings and Risk Factors for Brain Injury in Foetuses Treated for Anaemia

OBJECTIVE: Characterize neuroimaging findings in foetuses with anaemia and identify associated risk factors. METHODS: Retrospective cohort study of pregnancies with foetal anaemia (defined as haemoglobin > 2 standard deviations below the gestational age mean) confirmed by foetal blood sampling (FBS) and treated with intrauterine transfusion (IUT) at a tertiary centre between 2011 and 2024. Prenatal and/or early postnatal neuroimaging findings and perinatal outcomes were reviewed. Multivariable logistic regression was used to identify factors associated with brain injury on neuroimaging. RESULTS: Of 100 foetuses with foetal anaemia that underwent neuroimaging, 93 met the eligibility criteria. Brain injuries were identified in 48 foetuses (52%). Injuries included intracranial haemorrhage (48%), ischaemia (21%), combined injury (6%), and non-specific injuries (25%). Imaging was performed prenatally (n = 36), postnatally (n = 36), or both (n = 21). Male sex was independently associated with brain injury (adjusted OR 5.04, 95% CI 1.64-15.52; p = 0.005). Anaemia severity, hydrops, cardiac dysfunction, and gestational age at diagnosis were not associated with brain injury. Immediate postnatal outcomes did not differ between the groups. CONCLUSION: In a clinically selected cohort of foetuses with anaemia who underwent neuroimaging after IUT, brain injuries were frequent and heterogeneous. These findings support the need for prospective studies with standardized imaging and longitudinal follow-up to define true risk and identify subgroups most likely to benefit from surveillance.