Prospective clinical evaluation of an improved fluorescence polarization assay for predicting fetal lung maturity.
We performed a prospective clinical evaluation of our newly developed fluorescence polarization procedure to predict fetal lung maturity (Clin Chem 1986;32:248-54). Net fluorescence polarization was measured at 34 degrees C after a 6.5-min incubation of amniotic fluid with fluorophore. For the 26 cases of neonatal respiratory distress syndrome encountered in 196 deliveries, the net polarization exceeded 0.287 for 22 (85%) of these, and exceeded 0.260 for all 26. The specificity of the polarization assay equaled or exceeded the specificity of the lecithin/sphingomyelin ratio for all sensitivities greater than 70%. Neither assay was a good predictor of the clinical severity of respiratory distress. For a separate group of 21 amniotic fluid specimens clinically contaminated with blood or meconium, the discriminatory power of the polarization assay was decreased, but six of seven respiratory-distress cases still had polarization values greater than 0.260. We conclude that this fluorescence polarization assay is a better overall predictor of fetal lung maturity than is the lecithin/sphingomyelin ratio, and that polarization values less than 0.260 are associated with little risk of respiratory distress.
D000653:Amniotic Fluid / Q000032:analysis; D005260:Female; D005325:Fetal Organ Maturity; D005454:Fluorescence Polarization / Q000379:methods; D006801:Humans; D008168:Lung / Q000196:embryology*; D010713:Phosphatidylcholines / Q000032:analysis; D011247:Pregnancy; D011446:Prospective Studies; D013109:Sphingomyelins / Q000032:analysis
D010713:Phosphatidylcholines; D013109:Sphingomyelins