Background Administration of antenatal corticosteroids in pregnancies with absent or reversed end-diastolic flow (A/REDF) on umbilical artery Doppler results in transient improvement in flow in two-thirds of pregnancies. It has been hypothesized that persistent abnormalities may be associated with poorer perinatal outcomes.

Aim To determine whether umbilical artery Doppler unresponsiveness to antenatal steroids in growth restricted fetuses is predictive of perinatal outcomes in babies born preterm.

Methods Retrospective cohort study of singleton pregnancies with umbilical artery A/REDF, who had Dopplers performed before and after steroids. Outcomes were compared in pregnancies with and without a response. Cases were identified from ultrasound records. Maternity, neonatal and follow-up records were reviewed. Outcomes included gestation at delivery, birth weight, perinatal mortality and significant neonatal morbidity (bronchopulmonary dysplasia, intracranial haemorrhage, necrotizing enterocolitis and retinopathy of prematurity) and neurodevelopmental disability at 2 years corrected age. Data were analyzed with χ².

Results 46 pregnancies were eligible for inclusion and 2 year paediatric follow-up data available for 28 babies <32 weeks gestation. Mean gestation at delivery was 28 weeks. Corticosteroids were associated with transient improvement in Dopplers in 18/46 (39.1%). Lack of response to steroids was associated with higher rates of composite neonatal morbidity and mortality (56.7% vs 21.4%, p<0.05) and moderate/severe neurodevelopmetal disability at 2 years of age (21% vs 0%, p<0.0001).

Conclusion Transient improvement in EDF was observed less frequently than reported previously. Lack of improvement in EDF appears to be a marker for poorer perinatal outcome and neurodevelopmental disability at 2 years of age.