Amniotic fluid OD 650 as a rapid indicator of fetal pulmonary maturity.
Amniotic fluid OD 650 (optical density at 650 nm) greater than 0.15 has been associated with mature L/S ratios. This study compared OD 650 with the L/S ratio on 235 uncontaminated amniotic fluid specimens. Follow-up was obtained on 138 neonates delivered within 72 hours of amniocentesis. Of 124 amniotic fluid specimens with OD 650 greater than 0.15, 109 had mature L/S ratios. Only 3 of 96 neonates with OD 650 greater than 0.15 developed respiratory distress syndrome; 8 of 42 neonates with OD 650 values less than 0.15 developed it. The false-positive rate (2.1%) compared favorably with that of the L/S ratio (2.9%). A higher false-negative rate (24.6%) decreased the efficiency of OD 650 as an indicator of fetal pulmonary maturity. An OD 650 greater than 0.15 appears to be a rapid, reliable indicator of fetal lung maturity.
D000653:Amniotic Fluid / Q000032:analysis / Q000502:physiology*; D002498:Centrifugation; D002855:Chromatography, Thin Layer; D005189:False Positive Reactions; D005260:Female; D005325:Fetal Organ Maturity; D006801:Humans; D007231:Infant, Newborn; D010713:Phosphatidylcholines / Q000032:analysis; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000378:metabolism; D012127:Respiratory Distress Syndrome, Newborn / Q000378:metabolism; D012189:Retrospective Studies; D013053:Spectrophotometry; D013109:Sphingomyelins / Q000032:analysis
D010713:Phosphatidylcholines; D013109:Sphingomyelins