Open AccessPhospholipids and Creatinine in Amniotic Fluid in Relation to Gestational Age: I. Normal Pregnancy
Author(s) -
Fex Göran,
Holmberg NilsGunnar,
Löfstrand Tord
Publication year - 1975
Publication title -
acta obstetricia et gynecologica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.401
H-Index - 102
eISSN - 1600-0412
pISSN - 0001-6349
DOI - 10.3109/00016347509157105
Subject(s) - medicine , creatinine , amniotic fluid , amniocentesis , pregnancy , gestation , lecithin , sphingomyelin , gestational age , phospholipid , endocrinology , obstetrics , gynecology , fetus , chromatography , cholesterol , chemistry , prenatal diagnosis , biochemistry , biology , membrane , genetics
. 185 samples of amniotic fluid were obtained from 174 healthy women with uncomplicated pregnancies in the 15th‐43rd week of pregnancy by abdominal amniocentesis or by puncture of the amniotic sac via an amnioscope. The concentrations of creatinine (183 cases), phospholipid phosphorus and the ratio of lecithin/sphingomyelin (L/S‐ratio, 130 cases) were determined. The treatment of the amniotic fluid samples (centrifugation, filtration and lipid extraction) and the methods for the determination of L/S‐ratio were examined and the accuracy and limitations of the latter method were defined and discussed. The relative amounts of lecithin and sphingomyelin as well as the L/S‐ratio and creatinine concentration were closely correlated to gestational age. A L/S‐ratio of ≥2.25 indicated all women to be ≥34th week of pregnancy; 64% of them had reached the 38th week. A creatinine concentration of ≥1.8 mg% corresponded to x ≥35th week of pregnancy, while 75% of the women had reached at least the 38th week. With a L/S‐ratio ≥2.25 and a creatinine concentration ≥1.8 mg% of all women were ≥ the 36th week. 71% of the women ≥ the 38th week fulfilled these critiera. A combination of the two parameters seems to be of a great value in discrimination between gestational ages < the 36th week and ≥ the 38th week.