Re: The role of antenatal corticosteroids in improving neonatal outcomes

Abstract

Dear Editor, We read with interest the article by Busuulwa et al. addressing the role of antenatal corticosteroids (ACS) in improving neonatal outcomes. We would like to add a few interesting points from the Antenatal Late Preterm Steroids (ALPS) study and recent meta-analysis evidence in support of the authors of the paper in being cautious about the use of ACS to improve neonatal outcomes in the context of late preterm deliveries (34–36 weeks’ gestation). Although late preterm deliveries account for approximately two-thirds of preterm infants, the recommendation for ACS for late pretermgestations has beenminimal,mainly because of the lack of randomised controlled trials (RCTs) and the possibility of long-term neurological impact outweighing short-term benefit. The ALPS study was the principal trial published in the literature and showed short-term respiratory benefits. The hypoglycaemia cutoff used by the ALPS study was very low: <2.2 mmol/L (widely accepted level <2.6–4.0 mmol/L); this suggests that hypoglycaemia incidence may be more than the 24% quoted in the study for the group who received steroids. Of note, hypoglycaemia is an independent predictor of poor neurodevelopmental outcomes in neonates. A recent meta-analysis by Mangesh et al., which included seven RCTs, showed reduced need for respiratory support in the steroid category (relative risk 0.68), while neonatal hypoglycaemia risk was high. Interestingly, the recent paper by Badreldin et al. showed no respiratory benefit of ACS in late preterm deliveries. Another high-risk group is neonates of type 1 and type 2 diabetic pregnant mothers, who have a 48% risk of hypoglycaemia. The National Institute for Health and Care Excellence guideline on diabetes in prenancy recommends delivery between 37 and 38 weeks, with either induction of labour or caesarean section. Steroid administration before delivery is standard practice for caesarean sections before 38 weeks. Steroid administration in this group poses an additional risk of neonatal hypoglycaemia on top of the baseline risk of 48% in neonates of diabetic mothers. For clinicians, there is a clinical dilemma (respiratory benefits versus neonatal hypoglycaemia in caesarean delivery at less than 39 weeks) because neonatal hypoglycaemia is associated with developmental delay, seizures, visual processing problems and cognitive difficulties, as well as hypoxic-ischaemic encephalopathy (HIE) and perinatal arterial ischemic stroke in the territory of the posterior cerebral artery. ACS in late preterm neonates therefore warrants cautious use until more RCTs on long-term outcomes can provide further recommendation.