Short- and long-term neonatal outcomes according to differential exposure to antenatal corticosteroid therapy in preterm births prior to 24 weeks of gestation

Abstract

Aim: To assess the effects of differential exposure to antenatal corticosteroid (ACS) on short- and long-term outcomes of infants born before 24 weeks of gestation.

Methods: This is a retrospective cohort study of 147 infants delivered by 116 women at 21-23 weeks of gestation between January 2001 and December 2016 at a tertiary referral hospital in Seoul, Korea. Eligible subjects were categorized into the following three groups according to ACS exposure: non-user (n = 53), partial-course (n = 44), and complete-course (n = 50). Univariable and multivariable analyses were used to compare neonatal mortality, neonatal morbidities including intraventricular hemorrhage (IVH), and neurodevelopmental impairment including cerebral palsy among the three groups.

Results: Neonatal mortality rate was significantly lower in the ACS-user groups (non-user, 52.8%; partial-course, 27.3%; complete-course, 28.0%; P = 0.01), but complete-course of ACS therapy had no advantages over partial-course. A lower incidence of IVH was observed in the complete-course group (non-users, 54.8%; partial-course, 48.6%; complete-course, 20.5%; P = 0.003). Multiple logistic regression analysis showed that ACS therapy, either partial- or complete-course, was associated with a lower rate of neonatal mortality (adjusted odds ratio (aOR) 0.375; 95% confidence interval (CI) 0.141-0.996 in partial-course; aOR 0.173; 95% CI 0.052-0.574) in complete-course). IVH (aOR 0.191; 95% CI 0.071-0.516) was less likely to occur in the complete-course group than in the non-user group. Neurodevelopmental impairment of survivors at 18-22 month after birth was not significantly different among the three groups.

Conclusion: ACS therapy in preterm births at 21-23 weeks of gestation was associated with significantly reduced rates of neonatal mortality and IVH, especially with complete administration.

Fig 1. Incidence of preterm birth at 21–23 weeks of gestation, neonatal mortality rate, infant mortality rate, and rate of ACS administration in preterm births at 21–23 weeks of gestation according to the time period; 2001 to 2004, 2005 to 2008, 2009 to 2012, and 2013 to 2016.

The incidence of preterm births at 21–23 weeks of gestation increased significantly over time (A). Neonatal mortality rate (B) and infant mortality rate (C) decreased over time, but without statistical significance. A significant increasing trend of ACS therapy was observed (D).