title: Amniotic fluid optical density determination as a rapid test for assessment of fetal lung maturity.
abstract: The lecithin/sphingomyelin (L/S) ratios and optical densities at 650 nm were determined for 158 samples of amniotic fluid obtained by amniocentesis. A further 24 samples collected by vaginal aspiration from patients with spontaneous rupture of the membranes were also analysed. The relation between the L/S ratio and the optical density suggests that the more rapidly obtainable optical density measurement could be used as a screening procedure for fetal pulmonary maturity. A valid estimate of maturity by optical density is not possible in amniotic fluid aspirated from the vagina.
mesh_terms: D000649:Amniocentesis; D000653:Amniotic Fluid / Q000032:analysis; D005260:Female; D006801:Humans; D008168:Lung / Q000196:embryology*; D010713:Phosphatidylcholines / Q000032:analysis; D011247:Pregnancy; D013053:Spectrophotometry; D013109:Sphingomyelins / Q000032:analysis; D014621:Vagina
chemical_list: D010713:Phosphatidylcholines; D013109:Sphingomyelins