Antenatal corticosteroids to prevent neonatal respiratory distress syndrome: risk versus benefit considerations.

The clinician considering administration of steroids to prevent respiratory distress syndrome (RDS) should attempt to identify patients who do not have criteria previously shown to increase the likelihood of benefit in the prevention of RDS. It is possible to accurately predict the interval to delivery in most cases. Four hundred thirty-nine patients at risk to deliver prior to 37 weeks have been screened for factors known to decrease the likelihood of benefit. Only 47 (10.7%) screened candidates have no exclusion criteria. Twenty-seven (6.9%) of 392 excluded neonates developed RDS; 20 of the 27 were predicted to and did deliver in less than 24 hours after initial screening. Only one case was inappropriately excluded. Fetal surfactant assessment is crucial; pulmonary maturity excludes 19% at 28 to 33 weeks and 35% at 34 to 37 weeks. Careful screening for exclusion factors known to decrease the likelihood of steroid derived benefit is essential when use of a drug with potential long-term consequences (risk) is considered.