Antenatal corticosteroid exposure and neonatal outcomes in term infants

Antenatal corticosteroids (ACS) are widely used to mitigate respiratory distress in preterm infants. Although the benefits of ACS in preterm births are well established, less is known about the short-term neonatal risks when ACS is administered during pregnancies that result in term delivery. Additionally, the impact of gestational age at the time of ACS exposure in this population remains unclear.

To evaluate the association between ACS exposure and short-term neonatal outcomes in term-born singleton infants, and further assess outcome variation by gestational age at exposure.

This retrospective, population-based cohort study used data from the Taiwan Maternal and Child Health Database and the National Health Insurance Research Database to compare term-born singleton infants exposed to ACS for threatened preterm labor with those unexposed, whose mothers had no diagnosis of preterm labor and no recorded ACS administration. Neonatal outcomes were analyzed using multivariable logistic regression.

Among 800,024 term births, 5577 (0.6 %) were exposed to ACS due to preterm labor. ACS-exposed infants had higher rates of SGA, CPAP, oxygen use, NICU admission, sepsis, hypoglycemia, TTNB, and jaundice (P < 0.001). Adjusted analyses revealed higher odds of SGA (aOR 1.30; 95 % CI 1.20-1.41), NICU admission (aOR 1.16; 95 % CI 0.99-1.36), and hyperbilirubinemia (aOR 1.49; 95 % CI 1.38-1.61) in the exposed group. Exposure between 28 and 33 weeks was associated with increased odds of oxygen therapy (aOR 1.42; 95 % CI 1.21-1.67) and TTNB (aOR 1.40; 95 % CI 1.00-1.94).

ACS exposure is associated with increased risks of short-term neonatal complications among term-born infants, especially when exposure between 28 and 33 weeks' gestation. Even when pregnancies end in term delivery, ACS exposure may still increase neonatal morbidity risk.