Assessment Of Fetal Lung Maturity Using Pulmonary Artery Doppler Indices: A Review Article

Abstract

This study highlights the role of fetal pulmonary artery Doppler as a reliable, non-invasive technique for assessing fetal lung maturity and predicting the risk of neonatal respiratory distress syndrome (NRDS). Conventional invasive procedures, such as amniocentesis, carry procedural risks, whereas Doppler evaluation offers a safe alternative by analyzing hemodynamic changes and vascular impedances. The main pulmonary artery acceleration time to ejection time (At/Et) ratio demonstrates a strong association with gestational age, lung maturity, and neonatal outcomes, with lower ratios indicating immaturity and higher RDS risk. Additional indices, including systolic/diastolic ratio, pulsatility index, resistance index, and peak systolic velocity, further strengthen its diagnostic performance. While the at/Et ratio alone may not achieve complete specificity across all gestational ages, combining it with other clinical parameters enhances predictive accuracy. By enabling early detection of at-risk fetuses, pulmonary artery Doppler can guide timely interventions, reduce neonatal morbidity and mortality, and improve overall perinatal care.