title: Pulmonary maturity studies in the evaluation of premature labor.
abstract: Amniocentesis was performed in 25 patients being treated with tocolytic therapy for premature labor, in an effort to determine the incidence of patients with mature lecithin/sphingomyelin (L/S) ratios and to discover a possible effect of tocolytic therapy on pulmonary maturity studies. Optical density measurements at 650 nm (OD650) and L/S ratio determinations were performed on the amniotic fluid. Repeat amniocentesis was performed in eight patients from 48 hours to 7 days after initiation of tocolytic therapy. There was a poor correlation between OD650 values of 0.150 or greater and L/S ratios of 2 : 1 or greater (64.3% false positives); and in the eight patients who underwent repeat amniocentesis, there was no significant change in the L/S ratio.
mesh_terms: D000649:Amniocentesis; D000653:Amniotic Fluid / Q000032:analysis*; D003720:Densitometry; D005260:Female; D005325:Fetal Organ Maturity / Q000187:drug effects; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000378:metabolism*; D007752:Obstetric Labor, Premature / Q000188:drug therapy; D010713:Phosphatidylcholines / Q000032:analysis*; D011247:Pregnancy; D011446:Prospective Studies; D013109:Sphingomyelins / Q000032:analysis*; D013726:Terbutaline / Q000008:administration & dosage
chemical_list: D010713:Phosphatidylcholines; D013109:Sphingomyelins; D013726:Terbutaline