title: Amniotic fluid lecithin-sphingomyelin ratio as a measure of fetal pulmonary maturity.
mesh_terms: D000653:Amniotic Fluid / Q000032:analysis*; D005314:Embryonic and Fetal Development; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D010713:Phosphatidylcholines / Q000032:analysis*; D011247:Pregnancy; D012129:Respiratory Function Tests; D012143:Respiratory Physiological Phenomena; D013109:Sphingomyelins / Q000032:analysis*
chemical_list: D010713:Phosphatidylcholines; D013109:Sphingomyelins