Endocrine Abstracts

Introduction: Infants born to mothers on antenatal steroid medication may develop adrenal suppression postnatally which can be potentially life-threatening. However, the incidence is unknown and screening for at risk infants is not universal.

Aim: The aim of our study was to review the outcome of infants born to mothers on antenatal steroids.

Method: We retrospectively reviewed our neonatal “paediatric alerts” for mothers on antenatal steroids between 2000 and 2009. Mothers on continuous oral steroid for >6 months before delivery were included in the study. Three cortisol levels were obtained at 8 hourly intervals on postnatal day 3. Adrenal suppression was defined as ≥2 levels of cortisol <100 nmol/l. All results are presented as mean±standard error of mean.

Results: Data were available for analysis in 50 appropriate patients. Nine (18%) patients had results consistent with adrenal insufficiency (mean cortisol 86±8.5 nmol/l). All 9 mothers were on prednisolone (mean daily dose 14±4 mg). Eight patients were started on replacement steroids. One (2%) patient on replacement steroids was admitted to hospital with adrenal crisis at 2 months old. All 8 patients on replacement steroids had normal synacthen test at 4 months old and steroids were stopped. Comparing patients with normal versus suppressed cortisol levels, mean maternal steroid dose (converted to prednisolone dose) was 16±2 and 14±4 mg respectively (P=0.70) and mean duration of maternal steroid therapy was 130±24 and 108±50 weeks respectively (P=0.70).

Conclusion: Adrenal suppression occurs in a significant proportion of infants born to mothers on antenatal steroids, independent of the duration or dose of maternal steroid therapy. Although this appears to be temporary, there is still a small risk of developing adrenal crisis. Screening for adrenal suppression postnatally is therefore recommended in infants at risk.