Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “AMNIOTIC FLUID”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,477 records · Page 82Linked to original sources
PubMed2003

[Maternal serum and amniotic fluid IL-1 alpha, IL-1 beta, IL-6 and IL-8 levels in preterm and term labor complicated by PROM].

UNLABELLED: Cytokines may be implicated in the pathophysiologic mechanisms of preterm and term labor. Many studies indicate cytokines as predictors of preterm delivery and explain partially mechanism of preterm uterine contractions. Complicated relations between mediators in systemic fluids of a fetomaternal unit require further explorations. The right diagnosis and management require better understanding of these relationships. OBJECTIVES: The comparison of IL-1 alpha, IL-1 beta, IL-6 and IL-8 levels in maternal serum and amniotic fluid in term and preterm labor complicated by PROM. MATERIAL AND METHODS: In 44 patients in premature labor with PROM (group I) and 33 patients in labor at term with PROM (group II) cytokines levels were estimated one time in amniotic fluid: just after PROM, and two times in maternal serum: just after PROM and during labor. RESULTS: Amniotic fluid cytokines levels were significantly higher in group I than in group II. Maternal serum cytokines concentrations of IL-1 alpha and IL-1 beta in group I were significantly higher than in group II. IL-6 level was significantly higher in group II than in group I. In both groups maternal serum IL-6 levels during labor significantly increased in comparison to IL-6 levels just after PROM. No correlations between amniotic fluid and maternal serum cytokine levels at PROM were observed. CONCLUSIONS: Higher amniotic fluid cytokines levels in patients with preterm labor complicated by PROM than in labor at term with PROM indicate possible differences between PROM mechanisms in preterm and term labor. The increase of IL-6 level during labor can be related with the possible role of this cytokine in the immunological mechanism of the labor beginning. No relationships between amniotic fluid and maternal serum levels of investigated cytokines in PROM suggest the presence of the barrier stopped cytokines transfer by the placenta and the complete separation of these two compartments.

Adult↗
PubMed1986

Lecithin-sphingomyelin ratios in amniotic fluid of pregnancies with an anencephalic fetus.

As many investigators have shown that surfactant production in the developing human lung is subject to multihormonal regulation, the present authors determined the lecithin-sphingomyelin (L/S) ratio in amniotic fluid of pregnancies with an anencephalic fetus, in which there was known to be aberrant production of fetal pituitary, adrenal, and consequently, placental hormones. The L/S ratio in amniotic fluid from seven of eight pregnancies with an anencephalic fetus was substantially lower than that in amniotic fluids of pregnancies with a normal fetus at the same stage of gestation. The L/S ratio in amniotic fluid of an anencephalic fetus of a twin pregnancy (monochorionic diamniotic) at 34 weeks' gestation was low; the L/S ratio of the amniotic fluid of the normal fetus was high. These data are supportive of the view that fetal lung maturation is dependent, in part, upon normal function of the fetal pituitary and adrenal.

Amniotic Fluid↗
PubMed1992

Blood and amniotic fluid contact sustained by obstetric personnel during deliveries.

OBJECTIVE: The objective of this study was to characterize blood and amniotic fluid contact sustained by obstetric personnel during deliveries. STUDY DESIGN: Trained observers collected data on 1376 person procedures during 230 deliveries at Grady Memorial Hospital from May to October 1989. Rates of contact were compared by means of the chi 2 test. RESULTS: At least one blood or amniotic fluid contact occurred during 79 (39.1%) of 202 vaginal and 14 (50.0%) of 28 cesarean deliveries; a needle stick occurred in 4 (2.0%) of the vaginal deliveries. Obstetricians and midwives had the highest rates of blood and amniotic fluid contact (18.7% and 28.8% of person procedures, respectively). Half of the contacts sustained by midwives might have been prevented by the use of gowns. Most contacts sustained by obstetricians might have been prevented by face shields, impervious gowns, and impervious shoe covers. CONCLUSIONS: Obstetricians and midwives had substantial risk of blood and amniotic fluid contact during delivery; many of their contacts were potentially preventable.

Amniotic Fluid↗
PubMed1987

Differential staining techniques in amniotic fluid cytology diagnosis of neural tube defects: a prospective study of 129 pregnancies.

In order to assess the utility of amniotic fluid cytology in the diagnosis of neural tube defects (NTDs), we performed a prospective study of 129 pregnancies selected for maternal age or history of prior congenital defects or multiple stillbirths. Amniotic fluid obtained between the 16th and 22nd weeks of gestation was cytocentrifuged and stained with hematoxylineosin (H&E), Papanicolaou, and Diff-Quik. Chromosomal analysis, amniotic fluid alpha fetoprotein (AFP) level, and eventual pregnancy outcome were recorded for each case. The AFP levels were normal in 128 cases, including two closed NTDs (meningomyelocele and encephalocele). Three patients had abnormal chromosomal studies: two with 47,XXX and one with trisomy 21. Of these 128 cases, 16 had inadequate cytologic preparations; the remainder, including the five aforementioned patients, showed predominantly squamous cells, amnion cells, and minicells. Other cell types, including genito-urinary cells, umbilical cord cells, respiratory cells, and macrophages, were also present in smaller numbers. One case exhibited a large population of small, darkly staining neural cells and large macrophages. The AFP in this case was markedly elevated, and the fetus was noted to be anencephalic. We found the H&E to be the preferred stain for both cytologic detail and minicell preservation; however papanicolaou was better for bloody specimens. Amniotic fluid cytology may provide a rapid and inexpensive method of confirming the diagnosis of open NTDs.

Amniotic Fluid↗
PubMedDate not supplied

S-100 protein in amniotic fluid of anencephalic fetuses.

S-100 protein, which is found essentially in the astrocytes of the nervous system, was assayed in amniotic fluids by Particle Counting ImmunoAssay. It was present in 19 cases of anencephaly out of 26, in 1 case of open spina bifida out of 5 and in each of the 4 cases of fetal death, whereas it was not detected in the 48 control amniotic fluids collected between the 16th and the 35th week of gestation. Thirty-one amniotic fluids from fetuses with other congenital malformations were devoid of detectable S-100. The presence of S-100 in amniotic fluid of anencephalic fetuses can presumably be considered as a biological sign of necrosis of the exencephalic brain and seems specific to damage of the central nervous system accompanied by neural tube defect.

Acetylcholinesterase↗
PubMed2002

Cytokine concentrations in the amniotic fluid during parturition at term: correlation to lower uterine segment values and to labor.

BACKGROUND: In previous studies a significant increase in interleukin (IL)-6 and IL-8 concentrations in the lower uterine segment parallel to cervical dilatation at term could be found, however only a weak correlation to duration of labor was detected. This study compares amniotic fluid concentrations of interleukin (IL)-6 and IL-8 with those in the lower uterine segment, and the duration of labor. METHODS: Amniotic fluid and lower uterine segment specimens were obtained from 29 patients during cesarean section at term. The patients were divided into groups according to cervical dilatation (< 2 cm, 2-3.9 cm, 4-6 cm, > 6 cm) and to labor (0 h, > 0-12 h, > 12 h). Interleukin-6 and IL-8 concentrations were determined by enzyme immunoassay. RESULTS: Amniotic fluid IL-6 already increased at 2-3.9 cm (p = 0.02), while the steepest increase in IL-8 was observed at > 6 cm (p = 0.003). No correlation with lower uterine segment values was observed for either of the cytokines. However, the amniotic fluid IL-6 concentration correlated with labor (p = 0.0008). CONCLUSION: The increase in the concentration of IL-6 in the amniotic fluid earlier than its increase in the lower uterine segment supports the hypothesis that IL-6 plays a crucial role for the promotion of labor in the first place, and afterwards for the biochemical degradation processes in the lower uterine segment. The fact that the greatest increase in IL-8 concentration occurs only at > 6 cm indicates that this chemotactic cytokine has only minor significance in the initiation of parturition by its concentration in the amniotic fluid.

Amniotic Fluid↗
PubMed1990

Bile acid metabolism in early life: studies of amniotic fluid.

Bile acid metabolism of the human fetus was examined in early gestation (weeks 13-19) and compared with the full-term fetus from the analysis of amniotic fluid collected from healthy pregnant women. Total individual bile acids were determined by gas-liquid chromatography-mass spectrometry after solvolysis and hydrolysis of bile acid conjugates. Additionally, bile acids were separated according to their mode of conjugation by lipophilic anion exchange chromatography. Qualitatively the bile acid profiles of amniotic fluid in early gestation were similar and markedly different from those of full-term fetuses. Chenodeoxycholic acid was the major bile acid identified in early gestation and concentrations exceeded those of cholic acid, but by full term this relationship was reversed. Over 50 bile acids were identified in the amniotic fluids, these included C-1, C-4, and C-6 hydroxylated species and reflected primary hepatic synthesis by the fetus. At full term, 7 alpha,12 alpha-dihydroxy-3-oxo-4-cholenoic acid was one of the major bile acids identified in amniotic fluid. The monohydroxy bile acids lithocholic and 3 beta-hydroxy-5-cholenoic acids were present in significant proportions during early gestation, but by full term these accounted for only a few percent of the total bile acids. Quantitatively the total bile acid concentration of amniotic fluid was less than 4 mumol/l. The majority of bile acids were found to be glyco-, tauro-, and sulfate-conjugates. The more hydrophobic bile acids tended to be preferentially sulfated. These data indicate that significant and major changes in bile acid metabolism take place between early and late gestation in the human fetus.

Amniotic Fluid↗
PubMed1991

Ontogeny of surfactant proteins A and B in human amniotic fluid as indices of fetal lung maturity.

Surfactant proteins A and B (SP-A and SP-B) were measured in human amniotic fluid by ELISA and correlated with lecithin to sphingomyelin ratio (L/S), phosphatidylglycerol (PG), and perinatal outcome. Amniotic fluid SP-A, SP-B, and L/S increased with advancing gestation. SP-A was detected at 19 wk gestation and increased dramatically in the 3rd trimester of pregnancy. SP-B was first detectable at 31 wk gestation and increased significantly to term. SP-A was a more specific predictor of nonrespiratory distress syndrome (RDS) than L/S or SP-B; however, the sensitivity of SP-A in predicting RDS was less than L/S less than 2.0 (26.3 versus 82.3%, respectively). In 209 pregnancies assessed within 48 h of delivery, the sensitivity of SP-B in predicting RDS (nondetectable SP-B) was comparable to the L/S, however, SP-B = 0 was frequently observed in mature infants, limiting its specificity for prediction of RDS. The greatest sensitivity and specificity were achieved with the measurement of L/S less than 2.0 and negative PG, which correctly predicted 100% of the infants with RDS and 94% of those who did not develop the disorder. Measurement of SP-A or SP-B did not improve the prediction of RDS. SP-A, SP-B, and L/S were not affected by infant sex, Apgar score, rupture of membranes, size for gestational age, maternal diabetes, hypertension, or exposure to medications. SP-A, SP-B, and L/S were significantly elevated in amniotic fluid from black mothers. SP-A was significantly elevated in amniotic fluid from mothers who smoked during pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Amniotic Fluid↗
PubMed1983

Influence of phospholipid saturation on classical thin-layer chromatographic detection methods and its effect on amniotic fluid lecithin/sphingomyelin ratio determinations.

We compared seven techniques, commonly used for detection of amniotic fluid phospholipids in thin-layer chromatography, with respect to their sensitivity to saturation of the fatty acid carbon-chain of lecithin. The techniques fell into two classes: sensitive and insensitive; those classed as saturation sensitive were less than or equal to 10% as sensitive to fully saturated lecithin as to lecithin with singly unsaturated acid moieties. Color development increased with the number of carbon-carbon double bonds per molecule but required only a single unsaturated acid ester in either the alpha or the beta position. Mixtures of lecithins with defined saturation, when detected by saturation-sensitive methods, mimicked the uneven coloration of amniotic fluid lecithin bands, supporting the hypothesis that this uneven coloration results from natural saturation heterogeneity. Detection techniques representative of these classes are shown to give widely differing values for the lecithin/sphingomyelin ratio for actual specimens of amniotic fluid.

Amniotic Fluid↗
PubMed1995

The diagnostic value of amniotic fluid Gram stain examination and limulus amebocyte lysate assay in patients with preterm birth.

The purpose of this study was to determine the value of Gram stain examination and Limulus amebocyte lysate (LAL) test in the detection of intraamniotic infection. Ninety women with preterm labor and intact membranes (n = 55) or preterm premature rupture of membranes (PROM) (n = 35) who delivered prematurely were included in the study. Amniotic fluid was cultured for aerobic and anaerobic bacteria as well as for mycoplasmas. Amniotic fluid analysis included Gram stain examination and limulus amebocyte lysate tests. The prevalence of positive amniotic culture was 32.2% (29/90) and the most common isolate was Ureaplasma urealyticum. Patients with preterm PROM group had a higher rate of infection than those with preterm labor and intact membranes 57.1% (20/35) vs. 16.4% (9/55), respectively (p = 0.0001). We found a lower gestational age at delivery and lower mean birth weight in neonates born to mothers with a positive amniotic fluid culture than those with negative amniotic fluid culture. The combined use of Gram stain examination and LAL test had a sensitivity and specificity of 51.7% (15/29) and 95.1% (58/61) respectively for the detection of positive amniotic fluid culture. We conclude that Gram stain examination and LAL test are rapid, simple and specific tests that can be used to detect microbial invasion of the amniotic cavity except in patients with mycoplasmas infections.

Adult↗
PubMed1982

Prenatal diagnosis of open neural tube defects using the amniotic fluid acetylcholinesterase assay.

The most reliable tool at present for the prenatal detection of open neural tube defects is the amniotic fluid alpha-fetoprotein assay. Nevertheless its nonspecificity and false-positive results produced by fetal blood admixture and other less well-defined causes have spurred the search for a more specific test. Increased amniotic fluid acetylcholinesterase activity has been reported in association with open neural tube defects. The authors have assayed acetylcholinesterase in second-trimester amniotic fluid samples with previously determined alpha-fetoprotein values from 200 pregnancies with 96.5% of the outcomes known. These pregnancies were selected because of known fetal abnormalities or difficulties in prenatal diagnosis. High alpha-fetoprotein and acetylcholinesterase activity was detected in all 66 cases of open neural tube defects. The authors were able to reclassify correctly 89% of normal pregnancies with spuriously high alpha-fetoprotein by demonstrating no acetylcholinesterase band after slab gel in electrophoresis. Nine cases with a normal outcome but high alpha-fetoprotein values and acetylcholinesterase activity constitute the remaining false-positive results. Notwithstanding the false-positive results, which may have been due to undetected fetal blood admixture, the acetylcholinesterase gel electrophoresis assay is clearly a valuable adjunctive test to the alpha-fetoprotein assay for the prenatal detection of neural tube defects. Although no specific for open neural tube defects, acetylcholinesterase analysis by gel electrophoresis of amniotic fluid is significantly less influenced by fetal blood than is alpha-fetoprotein and, furthermore, may prove as reliable a diagnostic test for open neural tube defect.

Acetylcholinesterase↗
PubMed1976

Amniotic fluid bilirubin as a prognostic indicator in rhesus isoimmunization.

The bilirubin concentration in 654 amniotic fluids obtained by amniocentesis of 227 consecutive rhesus isoimmunized pregnancies is determined by the chloroform extraction method. The material is divided in 3 classes reflecting the severity of erythroblastosis. It is found, by means of graphical analysis that corresponding fractiles of the amniotic fluid concentrations of bilirubin in different gestational weeks imply an almost uniform prognosis. In terms of logarithm the various bilirubin fractiles seem to move parallel to and linear with gestational time. A prediction diagram is constructed, making it possible to estimate fetal prognosis from the concentration of amniotic fluid bilirubin.

Amniotic Fluid↗
PubMed1981

The thromboplastic activity of lung surfactant in amniotic fluid and its application to prenatal assessment of fetal lung maturity.

Based on the fact that both tissue thromboplastin and lung surfactant show lamellar structures under the electron microscope and belong chemically to lipoprotein, the thromboplastic activity of lung surfactant in amniotic fluid was studied by measuring plasma recalcification time. The results obtained were as follows (1) The surfactant fractions isolated from amniotic fluid and rabbit or pig lung showed the thromboplastic activity with dose response. (2) The thromboplastic activity of amniotic fluid increased with advancing gestational age. (3) It was found that the thromboplastic activity determined by plasma recalcification time was parallel with the surfactant concentration of amniotic fluid. (4) The shortening rate of plasma recalcification time in amniotic fluid could estimate well the risk of RDS, and the critical value for RDS was assumed to be about 33%.

Amniotic Fluid↗
PubMed2004

Meconium staining of amniotic fluid correlates with intestinal peel formation in gastroschisis.

Several studies in animal models demonstrate that peel formation in gastroschisis is due to the accumulation and activation of intestinal waste products (IWP) in the amniotic fluid. We reviewed our recent experience with gastroschisis and asked the following questions: First, does staining of the bowel and amniotic fluid with IWP correlate with intestinal peel formation? Second, what prenatal ultrasound findings indicate that peel formation is occurring in utero? Over two years, 16 neonates were treated for gastroschisis; twelve had been diagnosed by prenatal ultrasound and followed closely. Patients were grouped based on the presence of IWP in the amniotic fluid at the time of delivery (staining or no staining), and outcomes were reviewed. All neonates in the staining group (n=7) had a fibrinous peel present at the time of birth whereas a peel was absent in all neonates in the no-staining group (n=9). Matting of the bowel was seen by prenatal ultrasound in four patients in the staining group (0/8 in the no-staining group) and correlated with peel formation (Fisher's exact test p =0.007). Primary closure was done in 14 of the infants, and two required silo closure. In neonates with gastroschisis, staining of the amniotic fluid and bowel serosa with IWP correlated with intestinal peel formation. The ultrasound findings of matting correlated with both peel formation and staining with IWP. These results suggest that spillage of IWP into the amniotic fluid is one of the factors in peel formation in gastroschisis. Identification of matting of the bowel by prenatal ultrasound indicates formation of a peel.

Amniotic Fluid↗
PubMed2000

Thrombopoietin levels in cord blood plasma and amniotic fluid in fetuses with alloimmune thrombocytopenia and healthy controls.

To extend our knowledge of the kinetics of fetal thrombopoietin (TPO), we studied TPO levels in cord blood plasma and amniotic fluid collected from 15 fetuses considered to be at risk of fetomaternal alloimmune thrombocytopenia and also from 10 healthy controls at caesarean delivery. In the plasma of all 25 fetuses and newborn infants studied, TPO was detected above the lower limit of detection (7 pg/ml) and correlated inversely with platelet counts (r = -0.53, P = 0.006). At term, TPO detected in amniotic fluid was at significantly lower levels (7 pg/ml; range 0-22 pg/ml) than simultaneously obtained cord plasma TPO (114 pg/ml; range 43-201 pg/ml; P < 0.001). There was no correlation between levels of TPO in amniotic fluid and cord plasma or platelet counts. In the serial samples collected from the five fetuses with HPA-1a alloimmunization before 37 weeks' gestation, the TPO levels in amniotic fluid were significantly higher than at term (P = 0.013): from 22 to 28 weeks' gestation, 42 pg/ml (30-78 pg/ml); from 32 weeks', 24 pg/ml (17-33 pg/ml); at term, 8 pg/ml (4-13 pg/ml), correlating inversely with gestational age (r = -0.81, P = 0.003). Thus, TPO is present in amniotic fluid at levels apparently inversely related to gestational age. Whether these high levels seen early in pregnancy are normal or are associated with the HPA-1 alloimmunization remains to be shown.

Amniotic Fluid↗
PubMedDate not supplied

3,3',5'-Triiodothyronine concentrations in amniotic fluid at different stages of pregnancy.

Since it is feasible to detect reverse T3 (rT3) in amniotic fluid, we investigated the possibility as to whether measurements of amniotic rT3 could be useful in diagnosing fetal hypothyroidism during pregnancy. In 55 amniotic fluid samples, obtained at different stages of pregnancy, we have documented increasing concentrations of this hormone. The results obtained are conflicting with previous reports. The reason for this discrepancy is not clear, however methodological differences in rT3 determination should be taken in account. The large scatter of rT3 values in amniotic fluid suggests that the diagnosis of neonatal hypothyroidism based on measurement of rT3 may require caution.

Amniotic Fluid↗
PubMed1994

Amniotic fluid erythropoietin levels in normal and Down's syndrome pregnancies.

The aim of this study was to measure the levels of erythropoietin in amniotic fluid from normal and trisomy 21 pregnancies at 10 to 20 weeks gestation. Samples of amniotic fluid were collected from 142 women with singleton pregnancies after genetic amniocentesis; 110 had a normal fetal karyotype and 32 had trisomy 21. Erythropoietin was measured using a double antibody radioimmunoassay. Amniotic fluid erythropoietin levels in normal pregnancies increased from 10 weeks (mean 3.2 mU/ml; range < 2.0-6.3 mU/ml) to 20 weeks gestation (mean 7.9 mU/ml; range 2.0-11.5 mU/ml). There was a significant linear correlation between gestational age and erythropoietin levels (r = 0.543; P < 0.0001). For the 32 patients with trisomy 21 pregnancies the median multiple of the median (MoM) was 1.11 (range 0.42-2.1). There was no difference between erythropoietin levels in amniotic fluid from normal and Down's syndrome pregnancies (U = 2352, P = 0.75, 95% CI = -0.11, 0.18); (Mann-Whitney U-test).

Amniotic Fluid↗
PubMed1996

[Evaluation of fetal condition in pregnancy complicated by hypertension--biochemical assessment of amniotic fluid. I. Protein and lipid components and kidney maturation].

Sixty two samples of amniotic fluid were submitted to biochemical investigation including 31 samples from women with pregnancy complicated by hypertension (studied group with mean blood pressure 165 +/- 15/95 +/- 5 mmHg) and 31 samples deriving from healthy pregnant women (control group with mean blood pressure 118 +/- 10/74 +/- +/- 9 mmHg). In the studied group pregnancy induced hypertension, primary hypertension and nephrogenic hypertension scored 58%, 32% and 10% of cases respectively. Both investigated and control groups consisted of pregnant women with the same gestational age of 37 +/- 2 weeks (34-40 weeks). The following parameters of amniotic fluid were measured: 1) total protein, 2) albumin, 3) beta-lipoprotein, 4) cholesterol, 5) uric acid, 6) urea, 7) creatinine. Micromethods were used. Amniotic fluid deriving from women with pregnancy complicated by hypertension showed decreased concentrations of total protein, albumin and beta-lipoprotein. In pregnancy complicated by hypertension kidneys of the fetuses were estimated to be as mature as in the normal pregnancy within the same gestational age.

Adult↗