Comparison Between Amniotic Fluid Lamellar Body Count and Fetal Pulmonary Artery Doppler Indices in Predicting Fetal Lung Maturity

Neonatal respiratory distress syndrome (RDS) remains a major cause of neonatal morbidity and mortality. A recent epidemiologic study in the United States estimates that there are 80,000 cases of neonatal RDS each year, resulting in 8500 deaths and hospital costs in excess of $4.4 billion.

A number of biochemical tests have been developed to predict the risk of RDS and assist obstetric care providers in delivery timing. Amniotic fluid lamellar body count (LBC) is an important biophysical test, based on measuring the concentration of pulmonary surfactant in amniotic fluid. It can be effectively used to assess fetal lung maturity. A noninvasive test for fetal lung maturity (FLM) would be useful to minimize the need for invasive testing and would be more acceptable to women. Fetal pulmonary artery Doppler waveform acceleration/ejection time may provide a noninvasive means of determining fetal lung maturity with relatively acceptable levels of sensitivity, specificity, and predictive values.

The investigators will study 200 women with singleton pregnancies presented with prelabor preterm rupture of membranes or undergoing cesarean section (CS). Amniotic fluid lamellar body count (LBC) and fetal pulmonary artery Doppler will be done to all women. LBC and fetal pulmonary artery Doppler will be correlated with fetal outcome.

Quantitative data will be statistically represented in terms of mean ± standard deviation (± SD) while categorical data will be represented as frequency and percentage. Comparison of quantitative data will be done using Mann Whitney U test for independent samples while categorical data will compared using Chi squared test or Fisher exact test when appropriate. A probability value (p value) less than 0.05 will be considered significant.