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 433 records · Page 24Linked to original sources
PubMed1996

How frequently should the amniotic fluid index be performed during the course of antepartum testing?

OBJECTIVE: Our purpose was to evaluate the need for frequent amniotic fluid volume assessments in our antepartum testing unit. STUDY DESIGN: In a retrospective analysis of data accumulated over 1 year in our antepartum testing unit amniotic fluid index values performed at 3- to 4-day intervals were compared with follow-up values. Of 11,827 amniotic fluid index values, there were 6291 with follow-up values within 4 days. The results were stratified on the basis of the subsequent amniotic fluid index value and estimated gestational age. Comparisons were made relating to amniotic fluid index testing intervals of 4 versus 7 days. RESULTS: Patients with an amniotic fluid index > 8 cm had a 2.3% chance (128/5677) of having oligohydramnios (amniotic fluid index < or = 5.0 cm) in the next 4 days. Those patients with low-normal amniotic fluid index values (5 to 8 cm) had a 16.2% chance (96/593) of having oligohydramnios in the next 4 days. There were few patients with an amniotic fluid index < or = 5 cm who had subsequent amniotic fluid index values measured. Patients with an amniotic fluid index > 8 cm had a 2.2% chance (156/6946) of having oligohydramnios within 7 days, and those with low-normal amniotic fluid index values had a 16.3% chance (105/643) of having oligohydramnios with 7 days. Stratifying the results by gestational age reveals that patients at > or = 41 weeks of gestation had a 23.3% chance of having oligohydramnios within 4 days if the current amniotic fluid index was found to be 5 to 8 cm and a 7.4% chance if the current amniotic fluid index was found to be normal. Term (estimated gestational age of 37 to 40 weeks) patients had a similar risk of oligohydramnios in 4 days if the amniotic fluid index was low-normal (17.8%) but a risk of 3.6% if the amniotic fluid index was normal. CONCLUSIONS: For patients at < 41 weeks of gestation undergoing antepartum testing, weekly assessments of amniotic fluid index is probably adequate if the initial measurement is in the normal range (> or = 8 cm) because the risk of having oligohydramnios within 7 days is low (2.2%). For patients at < 41 weeks of gestation whose initial amniotic fluid index measurement is in the low-normal range (5 to 8 cm), a scheme of twice-weekly assessment is justified on the basis of a higher risk for an amniotic fluid index < or = 5 cm within 4 days (12.3%). For all patients at > or = 41 weeks of gestation, twice-weekly amniotic fluid index assessments are recommended regardless of the initial measurement.

Amniotic Fluid↗
PubMed1990

Characterization of insulin-like growth factor-binding protein in ovine amniotic fluid.

We have characterized an insulin-like growth factor (IGF)-binding protein present in ovine amniotic fluid. Using an activated charcoal-binding assay, whole amniotic fluid specifically bound approximately 20-30% of 125I-labelled human (h) IGF-II added, while the binding of 125I-labelled hIGF-I was minimal. Radioimmunoassay for IGF-I or -II in ovine biological fluids showed that values in amniotic fluid were 9- to 13-fold less than in fetal plasma, while gel filtration of amniotic fluid on Sephadex G-50 eluted with 1 mol acetic acid/l revealed no additional binding activity which had been complexed to IGFs at neutral pH. Together, these observations suggest that the binding activity in amniotic fluid is largely unsaturated. Competition studies for the displacement of 125I-labelled IGF-II binding to amniotic fluid by increasing amounts of unlabelled IGF-I or -II, using the charcoal assay, showed that IGF-II was 30-fold more potent than IGF-I. Scatchard analysis revealed a single class of binding site for IGF-II, with a binding affinity of 0.68 +/- 0.18 litres/nmol (mean +/- S.D., n = 3). Ligand blot analysis of amniotic fluid by separation on 8% SDS-PAGE, transfer to nitrocellulose membranes, incubation with 125I-labelled IGF-II and autoradiography revealed a single band of IGF-binding protein with approximate molecular size of 38 kDa. Additional IGF-binding species of 20, 28, 48 and greater than 180 kDa were present in ovine fetal plasma. Separation of amniotic fluid on Concanavalin A-Sepharose revealed that it had little carbohydrate content. These results show that ovine amniotic fluid contains an unsaturated, non-glycosylated IGF-binding protein with high affinity for IGF-II.(ABSTRACT TRUNCATED AT 250 WORDS)

Amniotic Fluid↗
PubMed1980

Diagnosis of meconium in amniotic fluids by nuclear magnetic resonance spectroscopy.

Some 40 samples of amniotic fluids were studied by nuclear magnetic resonance (NMR) spectroscopy as the first step in developing techniques for analysis of amniotic fluids in vivo without amniocentesis. It was found possible to distinguish amniotic fluids containing meconium (fetal feces) from all other kinds of amniotic fluids (hydramnios or normal fluids) by proton NMR, but precise chemical or cytological analysis seemed unavailable. Also reported are results of in vitro analysis of amniotic fluids, and of measurements performed in vivo on other biologic fluids to investigate possible in situ detection of pathological amniotic fluids.

Amniotic Fluid↗
PubMed1986

Interrelationship between amniotic fluid C-peptide and catecholamines in the last trimester of diabetic pregnancy.

Amniotic fluid concentration and content (amniotic fluid volume X concentration) of C-peptide and catecholamines (epinephrine, norepinephrine) and their interrelationship was studied in nine women with gestational diabetes, in 14 women with type I diabetes, and in 20 healthy control women between the thirty-sixth and thirty-ninth week of gestation. Mean amniotic fluid volume was significantly larger (p less than 0.05) in the type I diabetic group than in the control group. Mean concentration and content of amniotic fluid C-peptide were elevated in women with gestational diabetes, significantly so in women with type I diabetes (p less than 0.05) as compared with nondiabetic control women. Mean amniotic fluid catecholamine concentrations were lower, although not statistically so, in both insulin-dependent and gestational diabetic women than in control women. Mean amniotic fluid catecholamine content was higher, although not statistically so, in women with gestational diabetes than in control women. In the type I diabetic group, epinephrine content was significantly lower (p less than 0.05) and norepinephrine content significantly higher (p less than 0.05) than in the control group. A significant positive correlation between the content of norepinephrine and C-peptide was found in control women (r = 0.57; p less than 0.05) and in women with gestational diabetes (r = 0.75; p less than 0.05). The close interrelationship could indicate a parallel maturation of these two hormonal systems.

Adult↗
PubMed1979

[Determination of fetal infectious risk by bacteriological examination of the amniotic fluid after premature rupture of the membranes].

Amniotic fluid was obtained per vagina from 228 mothers with premature rupture of the membranes and examined bacteriologically. The aim was to assess the importance of amniotic fluid contamination and the risk of foetal infection in the absence of systematic antibiotic therapy in the mothers. The incidence of amniotic fluid contamination was apparently greater in those mothers who had received antibiotics although the proportion of neonates with a true infection (3%) was almost identical. The absence of selection of resistant organisms is indicated by the marked preponderance of streptococci and the scarcity of Gram negative enterobacteriacae. Thus it is reasonable not to give systemic antibiotics but to culture the amniotic fluid. Infection can then be anticipated and in affected neonates the appropriate therapy started immediately.

Amniotic Fluid↗
PubMed1979

Measurement, characterization, and source of somatostatin-like immunoreactivity in human amniotic fluid.

Somatostatin-like immunoreactivity (SLI) is widely distributed in tissues and biological fluids. To determine whether SLI is also present in amniotic fluid, samples obtained by amniocentesis from 30 normal and 27 abnormal pregnancies were studied by radioimmunoassay. Direct incubation of [(125)I-Tyr(1)]tetradecapeptide somatostatin (SRIF) with amniotic fluid resulted in 89% tracer degradation. Damage was reduced to <5% when samples were acidified and boiled before the assay. With this technique, SLI was detectable in all normal amniotic fluid samples; the mean level at 15-20 wk of gestation (320+/-55 pg/ml, n = 15) being 4.5 times higher than the mean at 32-43 wk (70+/-12 pg/ml, n = 15) (P < 0.001). In cases of preeclampsia (n = 6), gestational diabetes (n = 5), anencephaly (n = 1), and meningomyelocele (n = 1), SLI values were in the normal range, but in one juvenile diabetic and one patient with chronic renal failure, SLI was undetectable (<10 pg/ml). In a pair of monochorionic diamniotic twins, SLI levels were very different (33 and 197 pg/ml), which suggests that fetal factors are more important than materno-placental ones in determining amniotic fluid SLI. Serial dilutions of amniotic fluid showed parallelism with standard SRIF. When concentrates of pooled amniotic fluid were chromatographed on Sephadex G-25 columns, all SLI eluted in the void volume ahead of SRIF even after treatment with 8 M urea and dithiothreitol. This "big" SLI incubated in amniotic fluid showed 100% stability over 24 h at 37 degrees C, whereas SRIF was rapidly inactivated (t((1/2)) congruent with 7 min). Extracts of placenta and fetal membranes contained no SLI, but small amounts (6-20% of total amniotic fluid SLI) were found in cells from fresh fluid. Radioimmunoassay of SLI in extracts of seven paired cord arterial and venous plasma samples showed no arteriovenous gradient consistent with fetal origin of cord blood SLI. It is concluded that (a) amniotic fluid contains SLI which is of fetal origin and (b) normal levels vary with gestational age. The SLI has a higher molecular weight (>/=5,000) and is more stable in amniotic fluid than SRIF.

Amniotic Fluid↗
PubMed1992

Measurement of amniotic fluid volume: accuracy of ultrasonography techniques.

OBJECTIVE: Our purpose was to determine amniotic fluid volume by the dye-dilution technique and compare it with the amniotic fluid index, largest vertical pocket, and two-diameter pocket (defined as vertical x horizontal of the largest vertical pocket). STUDY DESIGN: This prospective study involved 40 women undergoing amniocentesis in late pregnancy to detect fetal lung maturity or evidence of chorioamnionitis. The amniotic fluid volume was quantified ultrasonographically by means of the amniotic fluid index, largest vertical pocket, and two-diameter pocket. During amniocentesis the fluid volume was calculated by the dye-dilution technique of Charles and Jacoby. RESULTS: Ultrasonographic measurements by amniotic fluid index, largest vertical pocket, and two-diameter pocket correctly predicted normal amniotic fluid and hydramnios (74%). A new measurement, two-diameter pocket, gave a significantly more accurate estimate of oligohydramnios than did amniotic fluid index (p < 0.002) or largest vertical pocket (p < 0.0003). CONCLUSION: All three indices are moderately accurate in identifying normal amniotic fluid volume and hydramnios. Two-diameter pocket is the most accurate test to predict oligohydramnios.

Adolescent↗
PubMed2007

Perinatal outcomes of pregnancies with borderline amniotic fluid index.

OBJECTIVE: Our aim was to determine whether a borderline amniotic fluid index observed during antepartum testing confers a significant risk of adverse perinatal outcome. METHODS: Between April 2001 and May 2005, uncomplicated gestations with a singleton non-anomalous fetus, who underwent weekly monitoring of amniotic fluid index (AFI) until delivery during the last trimester and who gave birth at our hospital, were identified for our study. Normal amniotic fluid volume and borderline amniotic fluid were defined as AFI of >10 and <24 cm and >5 and <10 cm, respectively. The groups were compared on maternal data, mode of delivery and perinatal outcomes such as fetal distress, intrauterine growth restriction and meconium fluid. RESULTS: A total of 90 cases were identified as borderline amniotic fluid and 277 cases as normal AFI. We observed significant increased incidences of admission to neonatal intensive care unit, intrauterine growth restriction, meconium-stained amniotic fluid, intrapartum fetal distress in the group with borderline amniotic index (P < 0.05). CONCLUSIONS: A borderline amniotic fluid index observed in antepartum testing during the last trimester carries an increased risk of adverse perinatal outcomes. These patients should be followed up carefully during the antepartum and intrapartum period.

Amniotic Fluid↗
PubMed1983

Choice of substrate in determining peroxidase activity in the amniotic fluid.

Peroxidase activity in the amniotic fluid has been measured with two different chromogens, O-dianisidine and p-phenylenediamine. No activity was demonstrable with the former substrate but was present with the latter. These results show that choice of substrate is important in determining peroxidase activity, especially in the amniotic fluid.

Amniotic Fluid↗
PubMed1995

Is the 15-in situ clone protocol necessary to detect amniotic fluid mosaicism?

OBJECTIVE: Our purpose was to evaluate the 15-clone analysis for detecting amniotic fluid mosaicism by the in situ method. STUDY DESIGN: A 10-year review was performed of all amniotic fluid mosaicism cases at two institutions using the in situ method exclusively, with sequential clonal analysis to determine the first and second clone in which the abnormal cell line occurred. RESULTS: Of the 28,497 amniotic fluid samples, 73 met criteria for amniotic fluid mosaicism by in situ method (0.26%). There were 54 cases (0.19%) with potential clinical significance (23 autosome and 31 sex chromosome mosaicism); 49 of the 54 cases (89%) were detected in the first six clones, including 22 of 23 involving autosomes and 27 of 31 involving sex chromosomes. In one of the six cases detected after clone 6 (46,XX/47,XX,+21) the mosaic cell line was present in 20% of the clones analyzed and was followed by a voluntary termination of the pregnancy. In the other five cases amniotic fluid mosaicism was present in < 20% of the clones; these included one case of 46,XX/47,XX+mar (15% amniotic fluid mosaicism, voluntary termination of pregnancy), two cases of 45,X/46,XY (10% to 12% amniotic fluid mosaicism, both normal at birth), and two cases of 45,X/46,XX (8% amniotic fluid mosaicism, lost to follow-up; 12% amniotic fluid mosaicism, voluntary termination of pregnancy). By limiting the analysis to six clones, approximately 20% of analysis time could be saved per case, but one autosomal amniotic fluid mosaicism case per 10,000 samples could potentially be missed. CONCLUSION: Reducing the number of clones analyzed by in situ method could result in increased efficiency, decreased costs, and minimal loss of sensitivity.

Amniotic Fluid↗
PubMed1982

Amniotic fluid lysozyme content in normal and abnormal pregnancy.

Amniotic fluid lysozyme content of 127 normal and 37 abnormal specimens obtained from women at various stages of gestation was measured in this study. Normal amniotic fluid lysozyme content increased gradually from the early stage of gestation to the late part of the 2nd trimester, and rapidly after 32 weeks gestation. These changes in amniotic fluid lysozyme content are similar to changes in amylase and creatinine content reported previously. However, high levels of lysozyme activity were exhibited in cases of diabetic pregnancy, premature rupture of membrane, and fetuses with digestive disorders. However, amniotic fluid lysozyme content was low in cases of fetuses with anencephaly. Lysozyme content in cases of Rh incompatibility and preeclampsia was considered to be in normal range. These results might indicate that the significance of lysozyme activity on amniotic fluid is considerably different than the significance of other parameters such as amylase and creatinine activity.

Amniotic Fluid↗
PubMed1983

Relationship between amniotic fluid volume and maternal plasma volume expansion.

Amniotic fluid and maternal plasma volumes were estimated in high-risk obstetric patients suspected of being hypovolemic. Excluding cases of intrinsic maternal or fetal disease, there were good (P less than 0.001) correlations between maternal plasma volume expansion and amniotic fluid volume. In the presence of oligohydramnios, there is usually maternal hypovolemia, and vice versa. Oligohydramnios may often be corrected by vigorous maternal plasma volume expansion, which is sometimes indicated in the treatment of cases of fetal distress. It is presumed that only when maternal plasma volume expansion is normal, is uterine perfusion sufficient to provide amniotic fluid formation in normal amounts. The varying amounts of amniotic fluid seen in normal pregnancies at term probably reflect the varying fetal activities of swallowing and voiding.

Adult↗
PubMed1979

Protease inhibitors in serum and amniotic fluid during pregnancy.

Antitryptic and antichymotryptic activities in amniotic fluid and maternal serum were measured at various stages of pregnancy using the caseinolytic assay method for proteases. The inhibitory activities increased up to 20 weeks in amniotic fluid and remained in the same range up to 30 weeks; a sharp fall was observed at term. In serum, there was a gradual rise of activities with peak values around 30 weeks. The decrease with further advance of pregnancy was not as sharp as in amniotic fluid. The ratios of antitryptic to antichymotryptic activities remained fairly constant (1.54 +/- 0.07) in amniotic fluid throughout pregnancy. In maternal serum the ratio varied over a range of 1.28 to 2.67 and the increase in antichymotryptic activity was relatively greater between 16 and 30 weeks resulting in a lower ratio between the two activities. Amniotic fluid was found to contain a higher proportion of a heat stable inhibitor compared to serum and its contribution to total antitryptic activity varied from 8.7 to 15.6 per cent.

Amniotic Fluid↗
PubMed1975

Fetal ingestion and metabolism of amniotic fluid protein.

Fetal swallowing, digestion, and utilization of amniotic fluid protein were studied in near-term rhesus monkeys in which 35S-protein, synthesized biologically from 35S-methionine, was injected into the amniotic sac. The half-time of the injected protein in amniotic fluid was 1.1 days, a figure consistent with findings of others that fetal swallowing represents the principal mechanism of clearance of amniotic fluid protein. On delivery at timed intervals up to 7 days after injection, evidence of progressive proteolysis along the fetal alimentary tract was found. The amnio acids liberated from protein hydrolysis were apparently utilized in protein synthesis in the gut wall as well as absorbed in fetal plasma, where they equilibrated rapidly with maternal plasma and amniotic fluid. Maximal amino acid radioactivity in these three compartments occurred 3 days after injection and was followed 1 day later by maximal fetal plasma protein radioactivity. Incorporation into protein of amino acids absorbed after hydrolysis was found in fetal lung, liver, skeletal muscle, and brain. The results indicate that ingested amniotic fluid protein undergoes proteolysis in the fetal alimentary tract and the amino acids thus made available are utilized in protein synthesis by the developing fetus. While this mechanism can provide only a relatively minor proportion (estimated at 10 to 15 per cent) of fetal nitrogen requirements, it may represent an important aspect physiologically by preparing the fetus for extrauterine nutrition. Moreover, the use of intra-amniotic nutrition as a mode of fetal therapy, while speculative at present, offers possibilities for the furture.

Amino Acids↗
PubMed1996

[Detection of erythropoietin in amniotic fluid].

OBJECTIVE: To investigate the concentrations of amniotic fluid erythropoietin in normal and risk pregnancies. MATERIAL AND METHODS: The concentrations of erythropoietin were measured in 150 samples of amniotic fluid. The samples were obtained by amniocentesis and amniotomia and were analysed using an enzyme-linked immunosorbent assay (ELISA). Results were available within 6 hours. The intra-assay variation was 6.4%, the inter-assay variation 7.2%. RESULTS: The range of erythropoietin concentration in all samples was between 0.23 and 80 U/L and in a defined group of normal pregnancies between 1.20 and 6.53 U/L (10%-90% percentile). Correlation was found between the concentration of erythropoietin and maternal hypertension (p = 0.0159), amnion infection syndrome in combination with premature birth (p = 0.0593), fetal growth retardation (p = 0.784), and base-excess (p = 0.0487). Elevated erythropoietin concentrations were found in a defined risk group with Apgar scores below 7 after 1 minute (p = 0.072) and after 5 minutes (p = 0.0037). There is a connection between postpartal transfer to the intensive-care unit and elevated erythropoietin concentrations (p = 0.073). No influence is exercised by the child's sex on the concentration of erythropoietin. No significant connection was found between the level of erythropoietin and smoking during pregnancy, volume of amniotic fluid and maturity at birth. A critical erythropoietin concentration could be postulated at 12 U/L. Children with higher levels showed heavy and severe disorders. CONCLUSION: Elevated erythropoietin levels in amniotic fluid indicate prolonged fetal hypoxaemia. Using the ELISA-technique a rapid prepartal determination of such situations is possible and might be helpful in the clinical procedure.

Adolescent↗
PubMed1977

Amniotic fluid infections in an African city.

Amniotic fluid infections were the most common cause of perinatal death in Addis Ababa, Ethiopia (21.8/1,000 live births). Most such infections appear to originate in the fetal membranes near the cervical os. The high rate of spread of these local infections into the amniotic fluid in Addis Ababa appears related to a lack of antimicrobial activity in amniotic fluids. Factors that adversely affected nutrition in the gravid woman, lack of prenatal medical care, and low water usage were associated with the high rate of fatal infections.

Amniotic Fluid↗
PubMed1988

CA 125 in tissues and amniotic fluid during pregnancy.

CA 125 was assayed in amniotic fluid and tissue extracts by immunoradiometric assay, and immunohistochemical studies were performed on paraffin-embedded sections of endometrium, decidua, and fetal membranes with the monoclonal antibody OC 125 used as primary antibody. The concentration of CA 125 in amniotic fluid changes during pregnancy so that levels of 800 to 1000 U/ml are found before 12 weeks. Thereafter, levels of 4000 to 10,000 U/ml are detected routinely. As term approaches, amniotic fluid CA 125 concentrations fall to a range of 1000 to 2000 U/ml. Levels of CA 125 in tissue extracts of secretory endometrium and decidua were 65,000 and 29,500 U/gm of tissue, respectively. CA 125 was readily detected on the apical surfaces of glandular epithelium and in the secretions of endometrial glands obtained throughout the menstrual cycle. It was also detected in the lumina of decidualized glands throughout pregnancy. No antigen was detectable within glandular epithelial cells. We have previously reported high concentrations of CA 125 in chorionic tissue extracts (42,000 U/gm) and low concentrations in amniotic tissue extracts (275 U/gm). In contrast to those findings, immunohistochemical techniques detected CA 125 within the intercellular canaliculi that surround amniotic epithelial cells but not in chorion. We conclude that the likely source of amniotic fluid CA 125 is the decidua and that it gains access to the amniotic fluid via the intercellular canalicular system that traverses the amniotic epithelium.

Amniotic Fluid↗
PubMed1980

Fetal origin of amniotic fluid insulin in the human mother.

To investigate the origin of insulin in amniotic fluid amniocenteses were carried out in pregnancies with live, dead and anencephalic fetuses. Amniotic fluid insulin of pregnant women bearing live fetuses was 9.0 +/- 2.1 microU/ml; in six women with dead foetuses amniotic fluid insulin was not detected. A significant positive correlation was observed between gestational age and the amniotic fluid concentration of insulin. In the amniotic fluid of the four women bearing anencephalic fetuses, the amount of hormone was within normal limits (10.0 +/- 1.4 microU/ml). Intravenous glucose administration (0.33 g/kg body weight) to the mother doses not influence levels of insulin in amniotic fluid, but brought about changes in amniotic fluid glucose concentration. These findings support the conclusion that human amniotic fluid insulin is of fetal rather than maternal origin.

Adult↗