Abstract
Objective Transient tachypnea of the newborn (TTN), a common neonatal respiratory morbidity,
is associated with failure of adequate clearance of fetal lung fluid. Glucocorticoids
have an important role in lung maturity and the mechanisms of lung fluid clearance.
The aim of this study is to assess the association between umbilical cord cortisol
levels and transient TTN in late preterm and term neonates delivered by elective cesarean
section (CS).
Study Design A case-control study of 37 newborns diagnosed with TTN (cases) was compared with
40 healthy newborns (controls). All infants were delivered by elective CS without
labor. Umbilical cord cortisol levels were measured using enzyme-linked immunosorbent
assay.
Results Mean cord cortisol levels were significantly lower in cases than controls (131.36
vs. 233.32 nmol/L, p = 0.0001; odds ratio [OR] = 3.7; 95% confidence interval [CI]: 1.40–9.53), respectively.
Cord serum cortisol correlated inversely with the duration of tachypnea and the respiratory
rate (r = − 0.678 and −0.535, respectively).
Conclusion Umbilical cord cortisol levels are significantly lower in newborns with transient
TTN, and lower cortisol levels are associated with an increased respiratory rate and
longer duration of admission. Antenatal glucocorticoids can be recommended for late
preterm delivered by CS.
Key Points
Umbilical cord cortisol levels were lower in late preterm infants with TTN.
Late preterm newborn with severe TTN and NICU hospitalization have lower cord cortisol
levels.
Antenatal glucocorticoids can be recommended for late preterm delivered by CS.
Keywords cord cortisol - transient tachypnea of newborn - TTN - late preterm - elective cesarean
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