Editor,—Professor Pharoah questions whether the increased rate of cerebral palsy among newborn infants who were randomly allocated early postnatal dexamethasone therapy in the trial by Shinwell et al 1 might be because dexamethasone increased survival of infants who were impaired before birth, and not because dexamethasone caused cerebral impairment.

However, two recent systematic reviews of randomised trials of postnatal dexamethasone therapy in infants …