The lecithin/sphingomyelin (L/S) ratio has been estimated in the amniotic fluid from 20 patients with a twin pregnancy. The values in each pair of amniotic fluids were closely related. If amniotic fluid from one sac only is available, it is suggested that a ratio of 2-5:1 is taken as the ...

Lecithin/sphingomyelin (L/S) ratio was measured and rapid surfactant test (RST) was performed on amniotic fluid samples drawn from 60 normal and 18 diabetic pregnancies, for determination of fetal lung maturity. The results were compared to the neonatal outcome. Comparison of L/S ratio and RST demonstrates a good correlation (95%) between ...

176 samples of amniotic fluid were obtained by abdominal amniocentesis from 69 women with complicated pregnancies (toxemia, diabetes mellitus or rhesus isoimmunization) in the 27th-43rd week of pregnancy. The concentration of creatinine (172 cases), the ratio of lecithin/sphingomyelin (L/S-ratio, 155 cases) and phospholipid phosphorus (155 cases) were determined and related ...

246 samples of amniotic fluid were obtained from 245 women with normal or complicated pregnancy near or at parturition. The lecithin/sphingomyelin (L/S) ratio was determined and retrospectively correlated with the clinical course of the neonate. Ten neonates developed hyaline membrane disease (HMD). The highest L/S-ratio in this group was 1.82. ...

Amniotic fluid was obtained by transabdominal amniocentesis in 51 women in the 29th-36th week of pregnancy. The lecithin/sphingomyelin ratio was determined. In 28 patients,the ratio was less than 2.2. Beta-methasone was given for three days to 14 of them; the rest served as controls. On the fourth day, a second ...

118 samples of amniotic fluid were taken from 102 patients in the 25th to the 43th week of pregnancy by amniotomy or by transabdominal amniocentesis. 76 samples were obtained from patients with normal pregnancies without evidence for either induction or retardation of lung maturity; they served to establish normal values. ...

Fetal pulmonary maturity based on visualization of one or both fetal knee secondary centers of ossification was assessed in 84 gravidas. Amniotic fluid lecithin/sphingomyelin ration of 2:1 or greater was the criterion of fetal lung maturity. It was concluded that when antenatal radiographs reveal the presence of both centers of ...

A patient with an unsuspected placenta percreta presented with intraperitoneal bleeding at 33 weeks' gestation. Because of the clinical picture and a lecithin/sphingomyelin ratio of 1:1, this patient was treated conservatively until 38 weeks' gestation when an L/S ratio test indicated fetal maturity. The pregnancy was successfully terminated by cesarean ...

The lecithin/sphingomyelin ratio in amniotic fluid is a method of predicting fetal lung maturity. The L/H ratios in certain high risk pregnancies are poorly correlated with the shake test. The L/S ratios in drug addiction methadone pregnancies and diabetic pregnancies do not have a high degree of correlation with normal ...

We have found the lecithin/sphingomyelin ratio of Gluck (L/S ratio) to be very useful for predicting respiratory distress. It correlated reasonably well with three other phospholipid values: the total lecithin content, the acetone-insoluble lecithin content, and the total lecithin/total phospholipids ratio. When the L/S ratio of amniotic fluid was greater ...

Amniotic fluid (AF) lecithin/sphingomyelin (L/S) rations were obtained in 223 pregnancies. Gestations complicated by maternal diabetes (71), vascular disease (50), and fetal growth retardation (47) were included. Elevated L/S ratios at 34 to 36 weeks' gestation were observed to accompany maternal vascular disease; higher rat;os were also related to fetal ...

The effect of dexamethasone on amniotic fluid lecithin-sphingomyelin (L/S) ratio was measured in 15 fetuses of 34 weeks or less of gestation. Six of the patients presented with premature rupture of the membranes. A rise in the L/S ratio is mature levels (two or more) was observed 24 hours to ...

During the prenatal period of development of the rabbit skeleton (days 21-30) the successive phases of fetal maturity can be distinguished by reference to the progress of ossification, particularly in the distal limbs and sternum. In the present study absent or incomplete ossification of sternebra 5 occurred in 8% of ...

The frequent necessity for termination of pregnancy before the spontaneous onset of labor requires that we be able to accurately predict fetal lung maturity. We have used amniotic fluid studies for evaluation of fetal lung maturity and have found that (1) a "fat" cell concentration of 30% or more, or ...

198 amniotic fluid samples, obtained from 14-42 weeks of 158 patients were assessed for amniotic fluid phospholipids (total phospholipids, lecithin, sphingomyelin, lecithin/sphingomyelin ratio). The TPLP and Lec-concentrations show significant rises in concentration after 34th week whereas the sphingomyelin concentration remains virtually constant during pregnancy. L/S ratio remains relatively constant smaller ...

One hundred and three samples of amniotic fluid from 21 normal and 64 medically complicated pregnancies were used for evaluating fetal maturity by measuring one or more of the following: the lecithin-sphingomyelin ratio (L/S), bilirubin concentration, creatinine concentration, and percentage of fetal fat cells. The rapid foam test for surfactant ...

Subcommissural organs of young and mature rabbits were analyzed for their content of arginine vasotocin by radioimmunoassay. Younger animals had significantly greater quantities of this peptide. There was no detectable arginine vasopressin or oxytocin in subcommissural organ extracts. It is concluded that the subcommissural organ represents, in addition to the ...

Lecithin has been measured in amniotic fluid, pharyngeal aspirate, fetal and maternal plasma and fetal membranes from the same pregnancy. In the amniotic fluid from a term pregnancy 79 per cent of the lecithin is found in the reconstituted precipitate of centrifuged fluid. It is suggested that the lecithin of ...

Development of parasympathetic and sympathetic reflexes controlling heart rate, vascular pressures, and blood flows was investigated in fetal lambs weighing 300-5,800 g (65-165 days' gestation). Cardiovascular responses to veratridine injections, atrial stretching, bilateral cervical vagotomy, and cholinergic blockade with atropine were used to test parasympathetic activities. Responses to propranolol and ...

In recent years fetal lung maturity has been assessed by chemical determination of lung surfactant components in the amniotic fluid. The variation in the results, however, limits the clinical usefulness of these methods. To establish reliable criteria for fetal lung maturity 98 specimens of amniotic fluid were obtained in the ...

185 samples of amniotic fluid were obtained from 174 healthy women with uncomplicated pregnancies in the 15th-43rd week of pregnancy by abdominal amniocentesis or by puncture of the amniotic sac via an amnioscope. The concentrations of creatinine (183 cases), phospholipid phosphorus and the ratio of lecithin/sphingomyelin (L/S-ratio, 130 cases) were ...

The validity of the assessment of the fetal age and pulmonary maturity was evaluated on 369 patients at various stages of normal pregnancy and complicated by diabetes, toxemia and fetal anencephaly. Gestational maturity was assessed by ultrasonic measurement of the fetal biparietal diameter and by analysing constituents of amniotic fluid ...

Maturation of female Cediopsylla simplex takes place on the pregnant rabbit and nestlings but not on the estrous doe. If matured fleas are transferred to the estrous doe their ovaries are resorbed.

The normal range and trends of the ratio between lecithin and sphingomyelin in the amniotic fluid, estimated on thin-layer chromatograms, have been established for the last trimester. The accuracy of the ratio as an index of fetal lung development and of the risk of neonatal respiratory distress has been confirmed. ...

Renal p-aminohippurate transport in rabbits increased rapidly from birth to 4 weeks of age and then declined to that observed in adults. Penicillin administration to pregnant does or newborn rabbits stimulated the developing transport system, but did not increase the peak observed at 4 weeks. Therefore the continued presence of ...