The probability of neonatal respiratory distress syndrome as a function of gestational age and lecithin/sphingomyelin ratio.

Abstract

We sought to define the risk of neonatal respiratory distress syndrome (RDS) as a function of both lecithin/sphingomyelin (L/S) ratio and gestational age. Amniotic fluid L/S ratio data were collected from consecutive women undergoing amniocentesis for fetal lung maturity at Yale-New Haven Hospital from January 1998 to December 2004. Women were included in the study if they delivered a live-born, singleton, nonanomalous infant within 72 hours of amniocentesis. The probability of RDS was modeled using multivariate logistic regression with L/S ratio and gestational age as predictors. A total of 210 mother-neonate pairs (8 RDS, 202 non-RDS) met criteria for analysis. Both gestational age and L/S ratio were independent predictors of RDS. A probability of RDS of 3% or less was noted at an L/S ratio cutoff of > or = 3.4 at 34 weeks, > or = 2.6 at 36 weeks, > or = 1.6 at 38 weeks, and > or = 1.2 at term. Under 34 weeks of gestation, the prevalence of RDS was so high that a probability of 3% or less was not observed by this model. These data describe a means of stratifying the probability of neonatal RDS using both gestational age and the L/S ratio and may aid in clinical decision making concerning the timing of delivery.

• Authors: Caryn St Clair, Errol R Norwitz, Karlijn Woensdregt, Michael Cackovic, Julia A Shaw, Herbert Malkus, Richard A Ehrenkranz, Jessica L Illuzzi
• Journal: American journal of perinatology (Am J Perinatol) Vol. 25 Issue 8 Pg. 473-80 (Sep 2008) ISSN: 1098-8785 [Electronic] United States
• PMID: 18773379 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Lecithins
• Sphingomyelins

Topics

• Amniotic Fluid (chemistry)
• Gestational Age
• Humans
• Infant, Newborn
• Lecithins (analysis)
• Logistic Models
• Respiratory Distress Syndrome, Newborn (epidemiology)
• Risk Assessment
• Sphingomyelins (analysis)