To investigate longitudinal changes in fetal lung elasticity using shear-wave elastography (SWE) before and after maternal antenatal betamethasone administration.
Approach:
Study Design: A retrospective observational study including 26 pregnancies between 24 and 34 weeks of gestation.
Measurement Technique: Fetal lung and liver elasticity were assessed using two-dimensional SWE before betamethasone administration, 1 min after treatment, and 24 h later.
Key Findings:
Fetal lung elasticity demonstrated a gestational age–dependent decrease, with significantly lower values at 32–34 weeks compared with earlier gestational ages.
Fetal lung elasticity decreased significantly at 24 h after betamethasone administration (from 1.87 ± 0.04 kPa to 1.72 ± 0.04 kPa, p = 0.0005).
No significant change in lung elasticity was observed 1 min after corticosteroid administration.
Liver elasticity remained unchanged throughout the observation period.
Interpretation:
SWE may detect changes in fetal lung mechanical properties following corticosteroid administration.
Limitations:
The study is retrospective and includes a small sample size of 26 pregnancies.
Further studies are needed to determine the clinical relevance of SWE findings.
Conclusion:
Fetal lung elasticity measured by SWE decreases within 24 h following antenatal betamethasone administration.
