To return to a concern expressed in a recent blog, there are animal models and some observational data that suggest that antenatal steroids (ANS) could have a negative effect on cerebral development, at least with the doses used currently. Among very preterm infants this is probably overshadowed by the positive effects on survival, early neonatal adaptation, and reduction in intraventricular haemorrhage. But when the benefits are more modest and short term, one might ask if the risk/benefit is positive.

A new systematic review and meta-analysis (Ninan K, et al. Evaluation of Long-term Outcomes Associated With Preterm Exposure to Antenatal Corticosteroids: A Systematic Review and Meta-analysis. JAMA Pediatr. 2022:e220483) is hampered, as always, by the quality of the original data included.

Almost all of the data are from observational cohort studies, and almost all of the data for infants born at term are from a single study, which I have mentioned previously, Raikkonen et al. Which means that the conclusions of the SR and meta-analysis are identical to the conclusions of Raikkonen.

At the very least, this analysis shows we must get better data. With so many babies exposed to ANS who later deliver at or near to term, if there truly is an adverse effect it is essential that it be accurately quantified. The modest benefit of ANS for late preterm deliveries, with an absolute reduction of 3% of babies with respiratory distress, coupled with the worrying data in this systematic review, also make it clear we should improve our efforts to focus ANS use in women who actually will deliver very preterm. For babies who do eventually deliver very preterm, the advantages, both in the short term, and as shown in this publication, in the long term, are clear.