title: [Exact determination of the lecithin/sphingomyelin ratio in amniotic fluid. Suggestion of a reference methods (author's transl)].
abstract: Pulmonary maturity of the fetus can be evaluated by the lecithin/sphingomyelin (L/S) ratio in amniotic fluid. To existing methods of lipid extraction, precipitation with acetone and chromatography, we add a simple and accurate estimation of sphingomyelins (S) and precipitated lecithins (Lp) without acid digestion. The method is reproducible (C.V. less than 9%) for the measurement of Lp/S ratio and gives with accuracy the concentrations of Lp, avoiding possible errors in interpretation of Lp/S. Our results show that at 35 weeks of normal gestation, Lp/S ratio is about 2 and Lp concentration, 10 mg/1.
mesh_terms: D000653:Amniotic Fluid / Q000032:analysis*; D002855:Chromatography, Thin Layer; D003720:Densitometry; D006801:Humans; D008055:Lipids / Q000302:isolation & purification; D008722:Methods; D010713:Phosphatidylcholines / Q000032:analysis*; D010743:Phospholipids / Q000302:isolation & purification; D013109:Sphingomyelins / Q000032:analysis*
chemical_list: D008055:Lipids; D010713:Phosphatidylcholines; D010743:Phospholipids; D013109:Sphingomyelins
vernacular_title: Determination precise du rapport lecithine/sphingomyeline dans le liquide amniotique: Proposition d'une methode de reference.