title: An evaluation of multiple tests and the lecithin-sphingomyelin ratio for determining gestational age.
mesh_terms: D000649:Amniocentesis; D000653:Amniotic Fluid / Q000032:analysis; D003404:Creatinine / Q000032:analysis; D003720:Densitometry; D005260:Female; D005865:Gestational Age; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008722:Methods; D010713:Phosphatidylcholines / Q000032:analysis*; D011247:Pregnancy; D013109:Sphingomyelins / Q000032:analysis*; D013223:Statistics as Topic
chemical_list: D010713:Phosphatidylcholines; D013109:Sphingomyelins; D003404:Creatinine