Hanaoka S, Iwanaga K, Tomotaki S, et al. - In the present study, the researchers sought to investigate the impact of antenatal corticosteroids (ANS) on the maturation of thyroid function in preterm infants. A study group of 99 very low birth weight neonates (< 34 weeks’ gestational age) except those born more than 7 days after ANS administration were classified into a complete group (n = 49) whose mothers completed two doses of betamethasone and who were born more than 24 hours after the completion of ANS administration, and an incomplete group (n = 50) who were not exposed to any ANS or were born within 24 hours after the completion of ANS administration. The prevalence of hyperthyrotropinaemia (TSH > 15 mIU/L) was significantly lower in the complete group relative to the incomplete group. According to multivariate logistic regression analysis, the incidence of hyperthyrotropinaemia was linked to complete ANS administration. Findings suggested that ANS administration in preterm neonates might facilitate thyroid maturation.