Supplementary Material for: Prenatal Diagnosis, Management, and Outcome of Fetal Subdural Haematoma: A Case Report and Systematic Review

Background: Fetal subdural haematoma (SDH) is associated with poor prognosis. Objective: The conflicting evidence from the literature presents a challenge in prenatal counselling. We present a case study and systematic review of the literature for the management and outcome of fetal SDH. Methods: Systematic search of electronic database. Results: A total 45 cases were extracted from 39 papers. Prenatal ultrasonographic features were intracranial echogenicity (42%), lateral ventriculomegaly (38%), presence of an intracranial mass (31%), macrocephaly (24%), midline deviation of cerebral falx (20%), and intracranial fluid collection (11%). Further secondary features were noted including reversed diastolic flow in the middle cerebral artery (11%), echogenic bowel (4%), hydrops fetalis (2%), and elevated middle cerebral artery peak systolic velocity (2%) (all highly likely to be associated with fetal anaemia). The rates of termination of pregnancy, stillbirth, and neonatal death were 18% (8/45), 16% (7/45), and 11% (5/45), respectively. Overall, therefore, the fetal and perinatal mortality was 32% (12/37). Amongst the 24 survivors with available neurological outcome, 42% (10/24) and 58% (14/24) had abnormal and normal neurological outcome, respectively. Underlying aetiology of fetal SDH was not identified in 47% (21/45). Fetal SDH with an identifiable underlying aetiology was the only factor associated with a higher chance of normal neurological outcome when compared to fetal SDH without a detectable cause (78.5 vs. 21.4%, p = 0.035). Conclusions: Stillbirth and neonatal death occurred in a significant proportion of fetal SDH. 58% of survivors had normal neurological outcome, and better prognosis was seen in SDH with identifiable underlying aetiology.