title: Optical density at 650 nm in amniotic fluid, L/S ratio and foam test as indicators of fetal lung maturity.
mesh_terms: D000653:Amniotic Fluid / Q000032:analysis*; D005260:Female; D005325:Fetal Organ Maturity; D006801:Humans; D008168:Lung / Q000196:embryology*; D008722:Methods; D010713:Phosphatidylcholines / Q000032:analysis*; D011247:Pregnancy; D013053:Spectrophotometry; D013109:Sphingomyelins / Q000032:analysis*
chemical_list: D010713:Phosphatidylcholines; D013109:Sphingomyelins