Assessment of Thyroid Functions in Late Preterm Infants of Mothers on Antenatal Steroids

Purpose: The study examined the effect of antenatal steroids on thyroid functions in late preterm infants on the third to the seventh day of life. Patients and Methods: A comparative Cross-Sectional study was conducted on 75 neonates admitted to NICU in the first week of life. They were divided according to exposure to antenatal steroids into three groups. First group: exposed to complete course of ANS. Second group: exposed to partial course of ANS. The third group: not exposed to ANS. Serum samples were obtained from selected cases free T3, Free T4, and TSH levels in the third day of life, compared to the cut of levels currently available (the TSH reference range is (1.7 to 9.1 mU per L), T4 should be greater than( 10 mcg per dL). Using Eleusis and Cubase analyzers kits (Roche Diagnostics, Indianapolis, IN, USA) by ELISA (enzyme-linked immune sorbent assay) technique. Results: The study showed that there were significantly higher serum T4 levels in group 1 that was exposed to a complete course compared to group 2 (partial course) and 3 (Third group). There were no significant differences in serum TSH, T3 levels between groups. The current study found a decreased incidence of the ROP, NEC and BPD among group 1 as compared to the other two groups although was non statistically significant. In addition, the complete course of ANS had delayed the date of delivery (P=0.04) as compared to the partial course in the current study. Conclusion: Antenatal corticosteroids can influence thyroid function in late preterm infants as serum T4 was significantly higher in infants exposed to complete course compared to those who were exposed to partial course or did not receive antenatal corticosteroids