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Biomedical subjects

M Mazor

Publications and source records attributed to M Mazor.

At least 217 records · Page 12Linked to original sources
PubMed1991

Meconium-stained amniotic fluid: a risk factor for microbial invasion of the amniotic cavity.

The purpose of this study was to determine whether meconium-stained amniotic fluid is a marker for microbial invasion of the amniotic cavity. Amniocentesis was performed on 707 patients presenting with preterm labor and intact membranes. Meconium-stained amniotic fluid was present in 4.2% (30/707) of patients with preterm labor. The prevalence of positive amniotic fluid cultures was significantly higher in women with meconium-stained amniotic fluid than in women with clear fluid (33% [10/30] vs 11% [75/677]; p = 0.001; odds ratio = 4.01; 95% confidence interval = 1.6 to 9.4). Patients with meconium-stained amniotic fluid were also more likely to have failed tocolysis and delivered a preterm neonate more frequently than patients with clear fluid (83% [25/30] vs 38% (258/677); p = 0.0001; odds ratio = 8.1; 95% confidence interval = 2.9 to 24.4). We conclude that meconium-stained amniotic fluid is a risk factor for microbial invasion of the amniotic cavity and preterm delivery in women with preterm labor and intact membranes.

Amniotic Fluid↗
PubMed1991

Fibrolamellar carcinoma of the liver in pregnancy. A case report.

Fibrolamellar carcinoma of the liver is a rare tumor that has not been previously reported to occur during pregnancy. A 22-year-old, pregnant Arab woman with documented fibrolamellar carcinoma of the liver was followed at our high-risk pregnancy unit. Despite the severity of the disease, the pregnancy and delivery were uneventful.

Adult↗
PubMed1991

[Leukocyte esterase in the rapid detection of intraamniotic infection].

Several lines of evidence support the view that premature rupture of the membranes and premature labor are associated with bacterial infection of the amniotic cavity. The standard method of diagnosing intraamniotic infection is amniotic fluid culture, but the results become available only after 72 hours. Methods for more rapid diagnosis of bacterial invasion are therefor needed. We examined leukocyte esterase activity for this purpose. Amniotic fluid obtained from 62 women in preterm labor was cultured for aerobic, anaerobic and mycoplasma species. Leukocyte esterase activity was measured with a Bio-dynamics test strip. The sensitivity of the test was 50.0% and its specificity 93.4%. It was found to be a simple and rapid method for the detection of intraamniotic infection.

Amniotic Fluid↗
PubMed1991

Reduced frequency of hypertensive disorders in placenta previa.

The isthmic segment of the uterine artery's ascending branch has a freer course and wider diameter than distal parts of the vessel. Therefore, we assumed that this arterial segment would provide better blood flow and prevent hypoxia of the trophoblast. As a result, placenta previa pregnancies would be complicated by hypertensive disorders less often than are pregnancies with normally implanted placentas. To test this hypothesis, 491 placenta previa pregnancies, among a population of 106,866 pregnant women, were compared with pregnancies with normally implanted placentas. Clinically meaningful and statistically significant reductions in the rates and risks of hypertensive disorders were found in placenta previa pregnancies (P = .002, relative risk = 0.44, 95% confidence interval 0.25-0.78). The differences persisted when primiparous and multiparous women were examined separately and when preterm and term deliveries were separated. In a multivariate logistic regression analysis, patients with placenta previa had a third of the risk for hypertensive disorders compared with pregnant women with normally implanted placentas (relative risk = 0.36, 95% confidence interval 0.20-0.64), even after controlling for parity and preterm or term delivery. In the same model, primiparity and preterm delivery were each associated with a doubling of risk for hypertensive disorders, regardless of the placental implantation site. Thus, regardless of parity and preterm or term delivery, placenta previa and hypertensive disorders are inversely related.

Adult↗
PubMed1991

Management of post-date pregnancy: a case control study.

Post-date pregnancy is associated with higher rates of perinatal mortality and morbidity. The purpose of the present study was to compare the outcome of 200 post-date pregnancies, managed according to our protocol, to a matched control group of 200 healthy pregnant women delivered at term. The management protocol was based mainly on the pelvic score and nonstress test. Higher rates of labor induction, meconium-stained amniotic fluid, fetal distress, instrumental deliveries and cesarean sections were found in post-date pregnancies than in the control group (40% vs. 3% P = 0.0001, 31% vs. 15.5% P = 0.00001, 18.5% vs. 9.5% P = 0.007, 8% vs. 3% P = 0.02, 12.5% vs. 4% P = 0.002 respectively). Neonatal birth weight in the study group was significantly higher than in the control group (3,484.3 +/- 410.7 vs. 3,218.4 +/- 407.8 g P less than 0.001). Despite these differences between the groups, the perinatal morbidity and mortality rates were similar. These results can be partially attributed to the early antenatal monitoring and intensive follow-up.

Apgar Score↗
PubMed1990

Infection and labor. VI. Prevalence, microbiology, and clinical significance of intraamniotic infection in twin gestations with preterm labor.

The purpose of this study was to establish the prevalence, microbiology, and outcome of microbial invasion of the amniotic cavity in twin gestation presenting with preterm labor and intact membranes. Amniocenteses were performed on both sacs of 46 women with twin gestations, preterm labor, and intact membranes. Indigo carmine was injected to ensure sampling of both amniotic sacs. Amniotic fluid was cultured for aerobic and anaerobic bacteria, Mycoplasma hominis, and Ureaplasma urealyticum. A positive amniotic fluid culture of at least one sac was noted in 10.8% (5/46) of patients admitted in preterm labor and in 11.9% (5/42) of women delivered of preterm neonates. Of the five patients with microbial invasion of the amniotic cavity, three had microorganisms isolated from both sacs. The presenting sac was involved in all cases, supporting an ascending route for microbial invasion of the amniotic cavity in twin gestation. Polymicrobial infection was found in three of the eight amniotic sacs with positive cultures. In two cases different organisms were isolated from each sac. All patients with positive amniotic fluid cultures were delivered of preterm infants within 48 hours of amniocentesis. Patients with positive amniotic fluid cultures presented with preterm labor at an earlier gestational age and with more advanced cervical dilatation than did women with negative amniotic fluid cultures. Clinical evidence of chorioamnionitis subsequently developed in two of five women with positive amniotic fluid cultures. The interval between amniocentesis and delivery was shorter in women with positive amniotic fluid cultures than in women with negative amniotic fluid cultures (median: 3.5 vs 168 hours, p less than 0.0001). Infants born to women with microbial invasion of the amniotic cavity had a lower median birth weight and a higher incidence of respiratory distress syndrome than those born to women with negative amniotic fluid cultures (birth weight: 1085 vs 1975 gm, p = 0.024; respiratory distress syndrome: 37.5% vs 8.3%, p = 0.04).

Amniotic Fluid↗
PubMed1990

Preterm delivery: a risk factor for retained placenta.

The purpose of this study was to determine whether preterm delivery, with and without intraamniotic infection, is a risk factor for retained placenta. This complication occurred more frequently in women with preterm vaginal delivery than in women with term vaginal delivery (9.1% [21/231] vs 1.1% [6/561]; p less than 0.00001; odds ratio = 9.25). There was no significant difference in the prevalence of retained placenta between women with preterm labor and intact membranes and those with preterm premature rupture of membranes (8% [10/125] vs 10.4% [11/106]; p greater than or equal to 0.05). A positive amniotic fluid culture or clinical chorioamnionitis was not associated with a higher incidence of retained placenta. This study indicates that preterm delivery is associated with an increased risk of complications of the third stage of labor.

Adult↗
PubMed1990

Amniotic fluid glucose concentration: a rapid and simple method for the detection of intraamniotic infection in preterm labor.

The purpose of this study was to determine whether amniotic fluid glucose concentrations is of value in the rapid diagnosis of intraamniotic infection. Amniocenteses were performed in 168 patients with preterm labor and intact membranes. Amniotic fluid was cultured for aerobic and anaerobic bacteria, as well as Mycoplasma species. The prevalence of positive amniotic fluid cultures was 13.6% (23/168). Patients with positive amniotic fluid cultures for microorganisms had significantly lower median amniotic fluid glucose concentrations than patients with negative amniotic fluid cultures (median 11 mg/dl, range 2 to 30 mg/dl vs median 28 mg/dl, range 3 to 74, respectively; p less than 0.001). Amniotic fluid glucose concentrations below 14 mg/dl had a sensitivity of 86.9% (20/23), a specificity of 91.7% (133/145), a positive predictive value of 62.5% (20/32), and a negative predictive value of 97.8% (133/136) in the detection of a positive amniotic fluid culture. Amniotic fluid glucose determination is a rapid, sensitive, inexpensive, and simple test for the detection of intraamniotic infection in women with preterm labor and intact membranes.

Amniotic Fluid↗
PubMed1990

Amniotic fluid interleukin-1 in spontaneous labor at term.

The regulatory signals responsible for the increased biosynthesis of prostaglandins during parturition have not been established. Interleukin-1 (IL-1) is capable of stimulating prostaglandin production by intrauterine tissues and is an inflammation mediator. It has been postulated as a signal for the onset of labor in the setting of intrauterine infection. A study was designed to determine if spontaneous labor at term was associated with changes in IL-1 activity in amniotic fluid. Such fluid was retrieved from 41 women in labor and from 39 women who were not in labor at term. Immunodetectable IL-1 beta was present in 22 of the 41 women in labor but in only 8 of the 39 women without labor. IL-1-like bioactivity was not different between the two groups at a dilution of 1:4, but at dilutions of 1:12, 1:36 and 1:108, amniotic fluid from women in labor had significantly higher bioactivity than that from women not in labor. A significant correlation was found between the bioassay and immunoassay results. Our data show that inhibitors of IL-1 bioactivity are present in amniotic fluid and suggest that in a subset of laboring women at term, an inflammatory reaction may play a role in triggering the onset of parturition.

Amniotic Fluid↗
PubMed1990

Changes in amniotic fluid concentrations of prostaglandins E2 and F2 alpha in women with preterm labor.

There is a paucity of data regarding the concentration of prostaglandins (PGs) in the amniotic fluid of women with preterm labor. The purpose of this study was to determine if preterm labor is associated with changes in amniotic fluid concentration of prostaglandins E2 and F2 alpha. Amniotic fluid was retrieved by transabdominal amniocentesis from women with preterm labor and intact membranes. Patients were classified into three groups according to the response to tocolysis and the presence or absence of intra-amniotic infection. PGE2 and PGF2 alpha were measured using specific and sensitive RIA kits. Amniotic fluid concentrations of PGE2 and PGF2 alpha were significantly higher in women with preterm labor and intra-amniotic infection than in women without infection, regardless of the response to tocolysis. These data suggest that both PGs are involved in the mechanism of preterm labor and may have prognostic value.

Amniotic Fluid↗
PubMed1989

Infection and labor. III. Interleukin-1: a signal for the onset of parturition.

The regulatory signals responsible for the increased biosynthesis of prostaglandins during parturition have not been established. Because interleukin-1 is capable of stimulating prostaglandin production by intrauterine tissues and is an inflammatory mediator, we propose that interleukin-1 may act as a signal for the onset of human labor in the setting of intrauterine infection. The purpose of these studies was to determine interleukin-1 activity in amniotic fluid and to establish its relationship with the onset of term and preterm labor. Amniotic fluid from 182 patients was assayed for interleukin-1 activity. Cell-associated interleukin-1 activity was detected in fluid obtained in the third trimester but not in fluid obtained in the second trimester of pregnancy, suggesting a maturational event in interleukin-1 production. The factor responsible for interleukin-1 activity had biochemical characteristics of interleukin-1 alpha (estimated molecular weight of 14 kilodaltons, isoelectric point = 4.9), and its activity was blocked with an anti-interleukin-1 alpha antisera. Women in spontaneous labor at term were likely to have fluid phase interleukin-1 activity in amniotic fluid than women who were not in labor at term. Preterm labor in the setting of intraamniotic infections was associated with significant interleukin-1 activity in amniotic fluid. This bioactivity was predominantly attributable to interleukin-1 beta. A strong correlation between interleukin-1 and amniotic fluid concentrations of prostaglandin E2 and prostaglandin F2 alpha was found in women in preterm labor. These findings support the hypothesis that interleukin-1 may play a role in the initiation of preterm labor associated with intraamniotic infection.

Amniotic Fluid↗
PubMed1989

Infection and labor. V. Prevalence, microbiology, and clinical significance of intraamniotic infection in women with preterm labor and intact membranes.

Amniotic fluid was retrieved by amniocentesis from 264 patients with preterm labor and intact membranes admitted to Yale-New Haven Hospital from Jan. 1, 1985, to July 31, 1988. The prevalence of a positive amniotic fluid culture was 9.1% (24/264). A total of 111 patients (42%) delivered preterm neonates, and 24 (21.6%) of those had positive amniotic fluid cultures. The diagnostic indexes of the Gram stain of amniotic fluid in the prediction of a positive amniotic fluid culture were as follows: sensitivity, 79.1%; specificity, 99.6%; positive predictive value, 95%; and negative predictive value, 98%. Endotoxin was detected with the limulus amebocyte lysate assay in 4.9% (13/264) of patients with preterm labor. All patients with endotoxin in the amniotic fluid delivered preterm neonates. The three most frequently isolated organisms were Ureaplasma urealyticum (n = 6), Fusobacterium species (n = 5), and Mycoplasma hominis (n = 4). Clinical chorioamnionitis was present in only 12.5% of the patients with positive amniotic fluid cultures. Women with positive amniotic fluid cultures had lower gestational ages and more advanced cervical dilatation on admission than women with negative cultures. Preterm infants born to mothers with positive amniotic fluid cultures had a higher incidence of respiratory distress syndrome and infectious complications than preterm neonates born after negative amniotic fluid cultures. These data underscore the frequency and importance of intraamniotic infections in women with preterm labor.

Amniocentesis↗
PubMed1989

Amniotic fluid concentrations of prostaglandin F2 alpha, 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) and 11-deoxy-13,14-dihydro-15-keto-11, 16-cyclo-prostaglandin E2 (PGEM-LL) in preterm labor.

Although prostaglandins (PGs) are considered the key mediators of human parturition at term, there is a paucity of data regarding their participation in the mechanisms responsible for preterm labor. The purpose of this study was to establish if preterm labor is associated with changes in the amniotic fluid concentrations of prostaglandins. PGF2 alpha, 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) and 11-deoxy-13,14-dihydro-15-keto-11,16-cyclo-prostaglandin E2 (PGEM-ll) were measured by using specific and sensitive radioimmunoassays. Amniotic fluid was retrieved by transabdominal amniocentesis from 55 women with preterm labor and intact membranes. Patients were divided into three groups according to the response to tocolysis and the presence or absence of an intra-amniotic infection. Amniotic fluid concentrations of PGFM and PGEM-ll were significantly greater in women with preterm labor and intra-amniotic infection than in women without infection. In addition, patients unresponsive to tocolysis without intra-amniotic infection also had a significantly greater concentration of PGFM and PGEM-ll in amniotic fluid than those responsive to tocolysis. Amniotic fluid concentrations of PGF2 alpha were greater in women with intra-amniotic infection than in women without intra-amniotic infection. In the absence of intra-amniotic infection, no difference in amniotic fluid PGF2 alpha concentrations could be found between women who responded to tocolytic treatment and those who did not.

Amnion↗
PubMed1989

Amniotic fluid arachidonate lipoxygenase metabolites in preterm labor.

This study was conducted to determine if preterm labor with intact membranes is associated with changes in the amniotic fluid concentrations of arachidonate lipoxygenase metabolites. Amniotic fluid was obtained by transabdominal amniocentesis from 68 women with preterm labor. The patients were classified into three groups according to their response to tocolysis and their amniotic fluid culture results: Group 1 - women with a negative amniotic fluid culture who responded to tocolysis (n = 32); Group 2 - women with a negative culture, but who failed to respond to tocolysis (n = 22); and Group 3 - women with intraamniotic infection (n = 14). The following arachidonate lipoxygenase products were measured by radioimmunoassay: leukotriene B4 (LTB4); leukotriene C4 (LTC4); 12-hydroxyeicosatetraenoic acid (12-HETE); and 15-hydroxyeicosatetraenoic acid (15-HETE). The median concentrations of LTB4 were significantly different among the three study groups (26 pg/ml, 67 pg/ml and 885 pg/ml, respectively, p greater than 0.05). Amniotic fluid concentrations of 12-HETE and LTC4 did not vary among the three study groups. On the other hand, a significant difference in the distribution of amniotic fluid concentrations of 15-HETE was noted only between women with intraamniotic infection (Group 3) and women responding to tocolysis (Group 1). These results indicate that the arachidonate lipoxygenase pathway is activated during the course of preterm labor. Selective changes in the concentrations of the assayed metabolites were noted. Amniotic fluid LTB4 concentrations may be a marker for the patient with preterm labor who is unresponsive to tocolysis.

Amniocentesis↗