Maximizing Benefit From Antenatal Steroid Use While Avoiding Overuse

To provide real-world data to inform benchmarking goals and practical issues that influence optimal antenatal corticosteroid timing and to examine patient factors, such as gestational age at steroid administration and presenting diagnoses, associated with steroid administration in relation to delivery.

This is a retrospective cohort study of singleton deliveries between July 1, 2016, and December 31, 2024, at two large academic hospitals with level IV neonatal intensive care units in a single health system. The primary cohort of interest was individuals who delivered between 24 0/7 and 33 6/7 weeks of gestation. The primary outcome of interest was the timing of antenatal corticosteroid administration in relation to delivery, categorized as none, delivery between 6 hours and 7 days after the first dose of antenatal corticosteroid ("optimally timed" per the Society for Maternal-Fetal Medicine's quality metric), and delivery less than 6 hours or more than 7 days after the first dose of antenatal corticosteroid ("suboptimally timed"). As a balancing measure to optimally timed antenatal corticosteroid administration, we also examined those who received antenatal corticosteroids before 34 weeks of gestation and delivered at term (after 37 weeks). We reported the rates of optimal timing and term delivery by their corresponding weeks of gestation and performed multivariable logistic regression modeling to understand patient factors and diagnoses associated with antenatal corticosteroid timing.

Among the 1,694 pregnant patients who delivered before 34 weeks of gestation, 961 (56.7%) had optimally timed antenatal corticosteroid administration, 162 (9.6%) received the first dose of antenatal corticosteroids less than 6 hours before delivery, 320 (18.9%) delivered more than 7 days after antenatal corticosteroid administration, and 251 (14.8%) did not receive antenatal corticosteroids. Of those who received antenatal steroids before 34 weeks of gestation, 747 of 2,879 (25.9%) delivered at term. There was little variation in optimal timing or term delivery by gestational age. Clinical factors associated with optimally timed antenatal corticosteroid administration compared with delivery more than 7 days after administration included pregnancy-related hypertensive disorder (adjusted odds ratio [aOR] 1.88, 95% CI, 1.31-2.69), preterm labor (aOR 2.78, 95% CI, 1.32-5.81), premature rupture of membranes (1.37, 95% CI, 1.33-1.42), anxiety disorder (aOR 079, 95% CI, 0.76-0.83), multiparous with no history of preterm birth (aOR 0.81, 95% CI, 0.77-0.86), placenta previa (aOR 0.76, 95% CI, 0.68-0.84), and placenta accreta (aOR 0.83, 95% CI, 0.81-0.85).

Achieving optimal timing of antenatal corticosteroid administration remains challenging. These findings underscore the need for improved prediction of preterm delivery and individualized patient assessment to ensure timely access to antenatal corticosteroids for women at risk of preterm birth while reducing unnecessary exposure.