title: Pharyngeal lecithin/sphingomyelin ratios in newborn infants.
abstract: Lecithin/sphingomyelin ratios were measured on hypopharyngeal secretions from newborn infants within 6 h of birth. L/S ratios of 1.8 or less correlated with the development of the idiopathic respiratory-distress syndrome. Low L/S ratios were more common in the shorter gestation infants, and there was a predominance of L/S ratios of more than 1.8 above 32 weeks' gestation. In multiple births, the first-born of triplets and quadruplets had higher L/S ratios than those subsequently born. This may indicate a link between fetal lung maturation and the onset of labour.
mesh_terms: D001722:Birth Order; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000196:embryology; D010614:Pharynx / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000032:analysis*; D011247:Pregnancy; D011783:Quadruplets; D012127:Respiratory Distress Syndrome, Newborn / Q000175:diagnosis*; D013109:Sphingomyelins / Q000032:analysis*; D013997:Time Factors; D014310:Triplets
chemical_list: D010713:Phosphatidylcholines; D013109:Sphingomyelins