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PubMed1984

Significance of brown and/or green amniotic fluid at the time of second trimester genetic amniocentesis.

During a two-year period, 83 discolored fluids (77 green, six brown) were obtained during genetic amniocenteses of 1227 patients. When compared with case-matched control subjects, those patients with discolored fluid had no differences in the incidence of spontaneous abortions, abnormal fetal karyotypes, infant abnormalities, occurrence of preterm labor, or requirement for delivery by cesarean section. The only statistically significant difference between control and test patients was that one in 83 versus 32 of 83 reported bleeding before amniocentesis (P less than .001). Both green and brown fluids had spectrophotometric peaks at 400 to 408 nm, similar to that reported for meconium. However, discolored fluid had measurable free hemoglobin, whereas meconium-stained fluid from term gestations did not, suggestive of an in utero hemorrhage. Further, when fetal blood, in concentrations calculated to yield a hemoglobin content similar to those measured in the discolored fluids, was incubated in amniotic fluid the spectrophotometric peak and absorbance units at 400 to 408 nm were similar to those for the discolored fluids. These observations are supportive of the hypothesis that blood breakdown products from an episode of intrauterine bleeding are responsible for the discolored fluid. Discolored amniotic fluid during second trimester, as an isolated finding, does not prognosticate a poor pregnancy outcome.

Amniocentesis↗
PubMed1995

Investigations into the rheological characteristics of bovine amniotic fluid.

The rheological characteristics of bovine amniotic fluid have been studied at different shear rates. The viscosity of bovine amniotic fluid at 20 degrees C was found to increase with time at a constant low shear rate during the measurement. Additionally, the viscosity was observed to decrease with increasing shear rate, indicating that a shear thinning behaviour of the fluid was occurring. The log-log plot of shear stress versus shear rate yielded a straight line consistent with non-Newtonian behaviour of the fluid and characteristic of pseudoplastic liquids. The data of shear stress versus shear rate could be represented by a power law model. The treatment of amniotic fluid with cetylpyridinium chloride (CPC) resulted in the precipitation of a mixture of components, including complex sulphated polysaccharides and extracellular proteoglycans, with the viscosity of the resulting liquid similar to that of water at 20 degrees C. In addition, the viscosity of the CPC-pretreated fluid did not increase with time at constant shear rate and remained constant with the increase in shear rate. The apparent increase in viscosity with time and the shear thinning behaviour of the amniotic fluid can thus be attributed to pseudoplastic liquid behaviour associated with the presence of structurally complex polysaccharides and extracellular proteoglycans. The implications of this fluid viscosity behaviour are discussed in terms of their impact on the operation of packed or expanded (fluidized) chromatographic bed systems when amniotic fluid biofeedstocks are used as a source of commercially important proteins.

Amniotic Fluid↗
PubMed2002

[Amniotic fluid embolism during labor].

Amniotic fluid embolism is an unpredictable but dramatical complication of pregnancy that occurs when amniotic fluid enter into the maternal circulation. The classical clinical feature is acute respiratory distress, circulatory distress, seizures and coagulopathy. However there is no routine laboratory diagnosis, so that is a diagnosis of exclusion. We report here the case of a patient, on labor with an epidural analgesia who suddenly suffered from seizures, circulatory arrest, and haemorrhage. A symptomatic management was instituted and a caesarean section was performed. An haemostatic hysterectomy was required. The patient survived without any sequelae. Neurological outcome of the child is still reserved.

Adult↗
PubMed1994

Inhibin and follistatin concentrations in fetal tissues and fluids during gestation in sheep: evidence for activin in amniotic fluid.

The concentrations of inhibin and follistatin in amniotic fluid and in tissue extracts from the placenta, gonads and adrenals of fetal sheep were measured using radioimmunoassays. These tissue extracts were from whole fetuses from days 16 to 45 and from the individual organs from day 46 to 145 (term) and were assayed at multiple dilutions. The capacity of these extracts to alter FSH production of rat anterior pituitary cells in culture was also assessed at multiple dilutions. Immunoactive inhibin concentrations in amniotic fluid from both sexes increased during gestation and levels were significantly greater in males than females. Peak concentrations of immunoreactive inhibin of 11.2 +/- 1.9 ng/ml were found in males at 116-125 days of gestation. Follistatin concentrations did not change throughout gestation and no significant difference was noted between sexes. Mean follistatin levels throughout gestation were 3.0 +/- 0.9 ng/ml for males and 3.7 +/- 0.9 ng/ml for females. Despite the potential for FSH inhibition by inhibin and follistatin, amniotic fluid from both sexes at all stages of gestation stimulated FSH secretion in the pituitary cell bioassays, suggesting the presence of activin which was confirmed by the measurement of immunoactive activin (13.3 +/- 2.5 ng/ml) in a specific radioimmunoassay. Maximum concentrations of immunoactive and bioactive inhibin in placental extracts were observed in late gestation (2.2 +/- 0.6 and 3.8 +/- 1.6 ng/g respectively) and there was no significant difference between sexes. Follistatin concentrations in placental cotyledons ranged from 11.5 to 27.1 ng/g with no significant difference between sexes. In view of the higher follistatin concentrations compared with inhibin, it is likely that the capacity of placental extracts to suppress FSH production by pituitary cells in culture is due predominantly to follistatin. Immunoactive inhibin was observed in high concentrations in the fetal testis throughout gestation; with concentrations increasing to a maximum of 1993.0 +/- 519.7 ng/g at 126-135 days of gestation with a ratio of bioactive: immunoactive inhibin of 1:20. Although bioactive and immunoactive inhibin was also observed in fetal ovaries and adrenals from both male and female fetuses, concentrations were lower than those observed in fetal testes. Follistatin concentrations in the fetal testis were elevated between 70 and 95 days (97.6 ng/g) and then declined. Similar concentrations were found in the adrenal glands of both sexes (males 83.5-103.3 ng/g: females 55.3-95.8 ng/g).(ABSTRACT TRUNCATED AT 400 WORDS)

Activins↗
PubMed2002

Absorption of amniotic fluid by amniochorion in sheep.

Swallowing of amniotic fluid and lung fluid inflow were eliminated in 10 chronically instrumented fetuses. The urachus was ligated, and fetal was urine drained to the outside. At the beginning and the end of 21 experiments of 66 +/- 5 (SE) h duration, all amniotic fluid was temporarily drained to the outside for volume measurement and sampling. Amniotic fluid osmolalities and oncotic pressures were experimentally controlled. Amniochorionic absorption of amniotic fluid depended strongly on the osmolality difference between amniotic fluid and fetal plasma (P < 0.001), but at zero osmolality difference there still was a mean absorption rate of 23.8 +/- 4.7 (SE) ml/h (P < 0.001). Absorption was unaffected by the protein concentration difference between amniotic fluid and fetal plasma, but infused bovine albumin in the amniotic fluid was absorbed at a rate of 1.8 8 +/- 0.4 g/h (P < 0.001), corresponding to a volume flow of fluid of 33.8 8 +/- 6.1 ml/h (P < 0.001). Fluid absorption in the amniochorion is driven in part by crystalloid osmotic pressure, but about 25 ml/h is absorbed by a path that is permeable to protein. That path has the physiological characteristics of lymphatic drainage, although no anatomic basis is known to exist for a lymphatic system in the amniochorion.

Absorption↗
PubMed1984

Immunoactive TSH in the amniotic fluid of the rat.

Amniotic fluid was obtained from 19-day-old rat fetuses by aspiration. Pooled samples measured at 4 different dilutions demonstrated parallelism with standard rat TSH. It is concluded that rat amniotic fluid has TSH immunoactivity.

Amniotic Fluid↗
PubMed2005

Monocyte chemotactic protein-1 is increased in the amniotic fluid of women who deliver preterm in the presence or absence of intra-amniotic infection.

OBJECTIVE: Pro-inflammatory chemokines have been associated with preterm parturition. Monocyte chemotactic protein-1 (MCP-1) is a chemokine capable of recruiting monocytes/macrophages into sites of inflammation, as well as stimulating the respiratory burst required for macrophage activation. MCP-1 transcripts and immuno-reactivity are expressed by uterine tissues (i.e., decidual cells and myometrium) and, thus, may participate in the process of labor. This study was conducted to determine if preterm labor leading to preterm delivery and intra-amniotic infection (IAI) are associated with changes in the amniotic fluid concentrations of MCP-1. STUDY DESIGN: A cross-sectional study was designed to examine the amniotic fluid concentrations of MCP-1 in women in two groups: 1) those presenting with preterm labor with intact membranes; and 2) those with preterm prelabor rupture of membranes (PROM). Amniotic fluid was obtained by transabdominal amniocentesis from 131 women in preterm labor with intact membranes and 105 women with preterm PROM. IAI was defined by a positive amniotic fluid culture for microorganisms. Group 1 included women with preterm labor and intact membranes (n=131), and was subdivided into the following groups: a) delivery at term in the absence of IAI (n=42); b) preterm delivery (< 37 weeks) in the absence of IAI (n=58); and c) preterm delivery in the presence of IAI (n=31). Group 2 consisted of women with PROM (n=105), and was subdivided into women with (n=51) and without (n=54) IAI. Non-parametric statistics were used for data analysis. RESULTS: 1) Immuno-reactive MCP-1 was detected in all amniotic fluid samples; 2) IAI, regardless of the membrane status, was associated with a significantly higher median amniotic fluid concentration of immuno-reactive MCP-1 than those without IAI (p<0.001 for both comparisons); 3) women in preterm labor who delivered preterm without IAI had a significantly higher median amniotic fluid concentration of immuno-reactive MCP-1 than those who delivered at term (p<0.001); 4) histological chorioamnionitis was associated with increased amniotic fluid concentrations of immuno-reactive MCP-1; and 5) a significant relationship existed between the amniotic fluid concentrations of immuno-reactive MCP-1 and the interval from amniocentesis to delivery. CONCLUSIONS: Amniotic fluid concentrations of immuno-reactive MCP-1 were increased in women in preterm labor with IAI, those without IAI who delivered preterm, and those who displayed acute inflammatory lesions in the extra-placental membranes. These findings suggest that MCP-1 may play a role in preterm labor regardless of the presence of IAI.

Adolescent↗
PubMed1992

How frequently should the amniotic fluid index be repeated?

OBJECTIVE: Our objective was to determine the most appropriate interval for assessing amniotic fluid volume with amniotic fluid index. STUDY DESIGN: In a retrospective analysis amniotic fluid indexes performed every 3 to 4 days in antepartum testing patients were compared with their follow-up values. Of 10,742 amniotic fluid indexes there were 7393 with follow-up values within 4 days. The results were stratified by current amniotic fluid index, gestational age, and concurrent nonstress test results. The groups were compared with chi 2 analysis. RESULTS: Patients with normal amniotic fluid index (> or = 8 cm) had a 0.54% chance of oligohydramnios developing in the next 4 days. Those patients with low normal amniotic fluid indexes (5 to 8 cm) had a 5% chance of oligohydramnios developing within the next 4 days, and patients with low amniotic fluid indexes (< or = 5 cm) had a 59% chance of persistent oligohydramnios 4 days after the index examination. Subdividing by gestational age demonstrated that patients > or = 41 weeks' gestation had a 2.6% chance of oligohydramnios developing within 4 days if current amniotic fluid index was between 8 and 15 cm. Results of concurrent fetal heart rate findings did not appear to change the risk for development of oligohydramnios. CONCLUSION: In patients < 41 weeks' gestation with normal amniotic fluid indexes, a repeat amniotic fluid index is not necessary for 7 days.

Amniotic Fluid↗
PubMed1983

Bulk flow of amniotic fluid water in response to maternal osmotic challenge.

Amniotic fluid volume is regulated by a complex system of fluid exchanges with fetal and maternal fluid compartments. To assess possible hormonal control of amniotic fluid water exchange with the maternal vascular compartment, we studied the effect of intra-amniotic injections of prolactin, vasopressin, or vasotocin on the amniotic to maternal water flux induced by the acute intravenous infusion of mannitol to the pregnant ewe. This mannitol stimulus increased amniotic fluid osmolality secondary to a shift of free water to the maternal vascular/extracellular compartments. Prior intra-amniotic injection of prolactin but not vasopressin or vasotocin blunted the amniotic fluid osmolar response to maternal mannitol infusion. These results suggest that resorption of amniotic fluid water may occur at the chorioamnion and that amniotic fluid prolactin may have a regulatory function in amniotic fluid volume and osmolar homeostasis.

Amniotic Fluid↗
PubMed1982

Functional bacterial opsonic activity of human amniotic fluid.

There are some data to suggest that amniotic fluid protects the fetus from invasion by pathogenic bacteria. To examine methods by which amniotic fluid may offer such protection, quantitative antibody, complement activity, and functional opsonic capacity were measured. Immunoglobulins were measured by laser nephelometry and total hemolytic complement was determined by radial diffusion; results suggested activity adequate for bactericidal capacity. The chemiluminescence assay was used to quantitate the functional interaction between polymorphonuclear leukocytes and E. coli, group B streptococci (GBS), or zymosan particles preopsonized with amniotic fluid obtained at different stages of gestation. Results were compared to those for normal serum. Data were analyzed by evaluation of the initial slope, area under the curve, and peak chemiluminescence response. Opsonic activity of amniotic fluid for E. coli and GBS was demonstrated, with E. coli showing greater reactivity (maximum = 15,000 to 25,000 cpm) than GBS (10,000 to 20,000 cpm). Specific, as well as nonspecific, opsonic activity was demonstrated by absorption of amniotic fluid with killed bacteria. Concentration of amniotic fluid did not result in an increase in chemiluminescent activity, which demonstrates that optimal opsonic activity already exists. The classical and alternate pathways of complement were assessed for E. coli and GBS. Preterm amniotic fluid did not differ in response from that of amniotic fluid obtained from term pregnancies. This study demonstrates that amniotic fluid can provide the fetus with protection from bacterial pathogens and delineates mechanisms for such protection.

Amniotic Fluid↗
PubMed2000

The role of amniotic fluid interleukin-6, and cell adhesion molecules, intercellular adhesion molecule-1 and leukocyte adhesion molecule-1, in intra-amniotic infection.

PROBLEM: To determine amniotic fluid concentrations and correlations of interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), and leukocyte adhesion molecule-1 (LAM-1) in patients with and without intra-amniotic infection. METHOD OF STUDY: Fourteen specimens with intra-amniotic infection and 45 without intra-amniotic infection were studied. Intra-amniotic infection was defined as the presence of a positive amniotic fluid culture. Amniotic fluid IL-6, ICAM-1, and LAM-1 levels were determined by an enzyme-linked immunoassay, and normalized by amniotic fluid creatinine levels. RESULTS: Amniotic fluid concentrations of IL-6 and LAM-1 were significantly higher in patients with than without intra-amniotic infection. However, amniotic fluid ICAM-1 concentrations were not significantly different between two groups. Amniotic fluid IL-6, LAM-1, and ICAM-1 were positively correlated. CONCLUSIONS: Our data indicate that amniotic fluid IL-6 is significantly associated with an increased adhesion molecule expression in intra-amniotic infection. However, LAM-1 plays a more important role than ICAM-1 in intra-amniotic infection.

Amniotic Fluid↗
PubMed1982

[Acute coagulation disorder following amniotic fluid infusion].

Penetration of amniotic fluid and its components into maternal circulation may cause more or less sizable obstruction of terminal sections of pulmonary circulation. Disseminated intravascular coagulation (DIC) will be the result of thromboplastic activity in amniotic fluid. Excessive fibrinolytic activity is likely to develop as counterregulation and to cause severe impairment of coagulation. The principle which governs the pathogenesis of such acutely acquired impairment of coagulation is discussed together with necessary diagnosis and therapy, with reference being made to two cases of differentiated courses.

Acute Disease↗
PubMed1988

Amniotic fluid 5-hydroxyeicosatetraenoic acid in preterm labor.

5-Hydroxyeicosatetraenoic acid (5-HETE) is an arachidonate lipoxygenase product capable of stimulating human uterine contractility in a dose-dependent manner in vitro. The purpose of this study was to determine if preterm labor is associated with changes in the concentration of this metabolite in amniotic fluid. Amniotic fluid was obtained by transabdominal amniocentesis from three groups of women with preterm labor: group 1 - women without intraamniotic infection who responded to tocolysis (n = 32); group 2 - women without intraamniotic infection who failed to respond to tocolysis (n = 22); and group 3 - women with intraamniotic infection (n = 14). 5-HETE was determined by radioimmunoassay. The median amniotic fluid concentration of 5-HETE in women who responded to tocolysis (median = 1412 pg/ml; range: 111-3547) was significantly lower than in women who delivered despite tocolysis (median = 2052 pg/ml; range: 136-7774) and women with intraamniotic infection (median = 1876 pg/ml; range: 543-7033) [p less than 0.05]). No difference in amniotic fluid concentrations' of 5-HETE were found between women in groups 2 and 3 (p greater than 0.05).

Adult↗
PubMed1987

[Secretory immunoglobulin A (S-IgA) in the amniotic fluid supports the fetal maturity profile].

Amniotic fluid levels of secretory immunoglobulin A(S-IgA) were measured by single radial immunodiffusion according to the method of Mancini using a monospecific antiserum against the human secretory component. 114 amniotic fluid samples were examined. The S-IgA values showed a correlation (r = 0.49) with the phospholipid levels. Additionally, it was observed no correlation between Serum and amniotic fluid S-IgA concentrations estimated as parallel investigations in 20 patients. S-IgA values greater than or equal to 82 mg/l were used to diagnose a sufficient fetal lung maturity. False negative values of S-IgA are possible. In 19 cases of newborns without signs of respiratory distress syndrome amniotic fluid S-IgA estimations were performed up to 32 hours before the delivery. False negative phospholipid levels were estimated in 2 cases, false negative S-IgA levels in 4 cases. The measurement of S-IgA in amniotic fluid will serve as an additional parameter for the estimation of fetal lung maturity.

Amniocentesis↗
PubMed1996

[Amniotic fluid embolism: review].

The amniotic fluid embolism, is a very uncommon syndrome but because of its severity and high mortality, it is interesting to study and to get a deep knowledge of its etiopathogenia and physiopathology. In this article, we revise the actually purposed pathogenic mechanisms, specially the humoral mechanisms in front of mechanical, as it was defended a few years ago. The diagnostic of this syndrome, is an interesting question, because it is not only pathology, actually it trends to immunologic diagnosis. The amniotic fluid embolism, interests to anesthesiologist and its differences in cardiopulmonary resuscitation in the pregnant woman too. All these data are discussed in our article, as much as treatment, that is based upon haemodinamics and cardiopulmonary resuscitation.

Amniotic Fluid↗
PubMedDate not supplied

Direct radioimmunoassay of human renin: comparison with renin activity in plasma and amniotic fluid.

Human plasma and amniotic liquid were activated by dialysis at pH 3.3. Then, renin before and after acidification was determined by two methods: enzymatic activity measurement, and direct radioimmunoassay. The identity between nonactivated and activated renin in plasma and amniotic fluid on the one hand, and pure renin on the other, was demonstrated by the dilution curves in radioimmunoassay. After acidification, mean plasma renin activity in 17 patients with high renin activity rose from 26.8 +/- 11.7 pmoles A I ml-1 h-1 to 67.9 +/- 29.3 pmoles A I ml-1 h-1, whereas the mean renin concentration tested by direct radioimmunoassay remained constant at 13.8 +/- 10.5 and 14.8 +/- 11.2 fmol/ml before and after acidification respectively. In amniotic fluid, renin activity increased from 9.7 to 227 pmoles angiotensin I/ml/h, but the renin concentration did not change. Direct radioimmunoassay of renin may therefore be considered as measuring total renin, regardless of its enzymatic activity. In 12 hypertensive patients undergoing bilateral renal-vein catheterization, the direct measurement of renin was very significantly correlated to the non-activated (r = 0.883) and activated renin values (r = 0.963).

Amniotic Fluid↗
PubMed1986

Diagnosis of intrauterine infection by demonstration of antibody-coated bacteria in the amniotic fluid.

Immunofluorescence examination of amniotic fluid for the occurrence of antibody-coated bacteria was carried out in 72 consecutive women with premature rupture of the fetal membranes to assess this method in the diagnosis of intrauterine infection. Antibody-coated bacteria were demonstrated in 11 women with clinical signs of intrauterine infection, histological amnionitis and heavy growth of one bacterial species. The presence of intrauterine infection was considered possible in another 14 women. One patient had no clinical signs of infection, but positive histological and bacteriological evidence; antibody-coated bacteria were demonstrated in this patient, but not in the remaining 13 women. In 47 women clinical, histological and bacteriological signs of intrauterine infection were absent, and examinations for antibody-coated bacteria were negative in all of them. It is concluded that the demonstration of antibody-coated bacteria in amniotic fluid indicates the presence of intrauterine infection, and the examination may in some cases be positive before the appearance of clinical signs of infection.

Amniotic Fluid↗