Infection In Preterm Labor Research Articles

A study of the relationship between placenta growth factor and gestational age, parturition, rupture of membranes, and intrauterine infection

Objective: Placenta growth factor is a potent angiogenic factor produced by the human placenta that has been implicated in the pathogenesis of preeclampsia and intrauterine growth restriction. Placenta growth factor belongs to the vascular endothelial growth factor family and is capable of inducing proliferation, migration, and activation of endothelial cells. The objective of this study was to determine the relationship between amniotic fluid concentration of placenta growth factor and gestational age, parturition (term and preterm), spontaneous rupture of the membranes, and intra-amniotic infection. Study Design: Amniotic fluid samples obtained from 273 pregnant patients were assayed in the following clinical groups: midtrimester pregnancy, preterm labor who delivered at term, preterm labor without microbial invasion of the amniotic cavity who delivered preterm, preterm labor with microbial invasion of the amniotic cavity, term not in labor, term in labor, term with microbial invasion of the amniotic cavity, preterm premature rupture of membranes with and without microbial invasion of the amniotic cavity, and term with premature rupture of membranes without microbial invasion of the amniotic cavity. The placenta growth factor concentrations were determined by an immunoassay that is both sensitive and specific. Results: Placenta growth factor was detectable in 96.3% (263/273) of samples. Amniotic fluid placenta growth factor concentration decreased with advancing gestational age (r = –0.42; P <.001). Amniotic fluid placenta growth factor concentrations were significantly higher in women in midtrimester pregnancy than in those at term not in labor (midtrimester pregnancy: median, 43.1 pg/mL; range, 22.9-69.8 pg/mL; vs term not in labor: median, 28.7 pg/mL; range, 16.1-82.7 pg/mL; P <.01). Neither term nor preterm parturition was associated with a change in amniotic fluid placenta growth factor concentrations. Term premature rupture of membranes was associated with a significant decrease in amniotic fluid placenta growth factor concentration (term premature rupture of membranes: median, 16.5 pg/mL; range <5.2-195.1 pg/mL; vs term intact membranes: median, 28.7 pg/mL; range, 16.1-822.7 pg/mL; P <.005). Preterm premature rupture of membranes was not associated with changes in amniotic fluid placenta growth factor concentrations. Intra-amniotic infection in preterm labor, term labor with intact membranes, and preterm premature rupture of membranes were not associated with changes in amniotic fluid placenta growth factor concentrations. Conclusion: Placenta growth factor is a physiologic constituent of amniotic fluid. Amniotic fluid concentrations of placenta growth factor decrease with advancing gestational age. Neither parturition nor infection affects amniotic fluid placenta growth factor concentrations. (Am J Obstet Gynecol 2000;182:1633-7.)

Amniotic Fluid Complement C3 as a Marker of Intra-amniotic Infection

Objective: To determine the value of amniotic fluid (AF) complement C3 as a marker of intra-amniotic infection and to compare complement C3 with other rapid markers of intra-amniotic infection. Methods: One hundred four women with singleton gestations, in preterm labor with intact membranes, at 23–35 weeks’ gestation underwent transabdominal amniocentesis. Amniotic fluid was analyzed for white blood cell (WBC) count, lactate dehydrogenase (LDH), glucose, Gram stain, and complement C3. Cultures for aerobes, anaerobes, and mycoplasma species also were performed. The median values of complement C3, WBC, LDH, and glucose were compared between the culture-positive and -negative groups. Complement C3 was compared with WBC count, LDH, glucose, and Gram stain for sensitivity, specificity, positive and negative predictive values, and accuracy in the prediction of a positive AF culture. Descriptive statistics, receiver operating characteristic curve, Fisher exact test, and Wilcoxon rank-sum test were used for analysis. Results: The prevalence of positive cultures was 11.5% (12 of 104). The culture-positive group had a significantly higher median C3 (7.0 mg/dL) than the median C3 (3.0 mg/dL) of the culture-negative group ( P < .001). Also, the median values of WBC (1120.5 cells/mm 3) and LDH (2697 U/L) were significantly higher and the median glucose (6.5 mg/dL) was significantly lower among women with positive AF cultures than among women with negative AF cultures (WBC = 1 cell/mm 3; LDH = 165 U/L; glucose = 45 mg/dL; P < .001). Eleven of the 12 culture-positive cases had a C3 of 5 mg/dL or more, whereas four of the 92 culture-negative cases had a C3 of 5 mg/dL ( P < .001). Nine of the 12 culture-positive cases but none of the 92 culture-negative cases had a C3 of 6 mg/dL or more ( P < .001). The relative risks of a positive AF culture were 65.27 (95% confidence interval [CI] 9.08, 469.27) and 31.67 (95% CI 10.40, 96.43) times greater among women with AF complement C3 levels of 5 and 6 mg/dL or more, respectively. Depending on the cutoff point used, complement C3 had similar or higher sensitivity, specificity, positive predictive value, and negative predictive value for intra-amniotic infection when compared with WBC count, LDH, glucose and Gram stain. Conclusion: Amniotic fluid complement C3 has value in the diagnosis of intra-amniotic infection in preterm labor with intact membranes. Complement C3 is available readily and compares favorably with other rapid markers of AF infection. This study supports the general concept of fetal inflammatory response to microbial invasion of AF.

Does lung maturation therapy with 16-methylene-prednisolone modify maternal infection parameters in threatened premature labor?

Silent intrauterine infection is a frequent cause of preterm labour. Maternal C-reactive protein (CRP) and leukocyte count are important predictors of such infections. Treatment with corticosteroids is known to elevate leukocyte count and in this manner can possibly interfere with its accuracy as a predictor of infection. Therefore, we investigated the impact of antenatal administration of 16-methylene-prednisolone (Decortilen solubile) on the maternal serum level of CRP and leukocyte count. Furthermore, we determined the haptoglobin, the platelet count as well as the percentage of stab cells and lymphocytes. 20 patients with preterm labour between 25 + 6 and 34 + 2 weeks of gestation were enrolled in a prospective study. Premature rupture of the membranes, uterine bleeding, infection and treatment with antibiotics were criteria for exclusion. Three doses (60 mg) of Decortilen solubile were given intravenously 24 h apart. Blood samples were obtained before, twice a day (8.00 a.m. and p.m.) during treatment and until the day 4 after termination of corticosteroid treatment. For statistical analysis the Wilcoxon rank sum test was used. Before corticosteroid treatment the medians (range) were: CRP: 5.2 ( < 5.0-28.0) mg/l, haptoglobin: 1.4 (0.7-2.0) g/l, leukocytes: 10.5 (5.2-16.0) G/l, platelets: 246 (128-424) G/l, stabs: 9.5 (3.0-14.0)% and lymphocytes: 28.5 (16.0-50.0)%. During the after termination of corticosteroid administration no significant changes in the CRP and haptoglobin levels were seen. The leukocyte count was unchanged during treatment and decreased on day 1-2 after termination of treatment. The platelet count remained unchanged during corticosteroid treatment and increased significantly thereafter. The stab cell percentage increased slightly from day 1-2 to day 3-4 after termination of treatment. The lymphocyte percentage increased during treatment and decreased significantly from day 1-2 to day 3-4 after treatment. Decortilen solubile treatment is not associated with an increase in maternal CRP-level and leukocyte count. We emphasise that the accuracy especially of the CRP for early prediction of silent infection in preterm labour does not seem to be impaired by this corticosteroid in a dosage usually administered for prevention of respiratory distress syndrome.

Amniotic Fluid Glucose Concentration: A Marker for Infection in Preterm Labor and Preterm Premature Rupture of Membranes

Amniotic fluid Gram stain and culture have been utilized as laboratory tests of microbial invasion of the amniotic cavity. The Gram stain of amniotic fluid has a low sensitivity in the detection of clinical infection or microbial invasion of the amniotic cavity, and amniotic fluid culture results are not immediately available for management decisions. Glucose concentration is used to diagnose infection in other sites such as cerebrospinal fluid. Objective: The purpose of this study was to evaluate the usefulness of amniotic fluid glucose concentration in detecting microbial invasion of the amniotic cavity associated with preterm labor and preterm premature rupture of membranes. Methods: Amniocentesis was performed in 60 women with preterm labor and/or preterm premature rupture of membranes. Gram stain and culture for Mycoplasma hominis, Ureaplasma urealyticum, aerobic, and anaerobic bacteria were performed. Subjects were studied prospectively for the development of positive amniotic fluid cultures and the development of clinical chorioamnionitis. Results: The diagnosis of clinical chorioamnionitis was made in 25% (15/60) of women entered into the study. Low amniotic fluid glucose concentration Was considered < 15 mg/dl. The sensitivity, specificity, and positive predictive value of low amniotic, fluid glucose concentration to predict clinical chorioamnionitis were 73.3%, 88.1%, and 68.8% respectively, while positive amniotic fluid culture, hada sensitivity of 43.8%, specificity of 79.5%, and positive predictive value of 43.8%. Conclusions: Amniotic fluid glucose concentration was more sensitive in predicting chorioamnionitis than either Gram stain or culture. Amniotic fluid glucose concentration was better in predicting clinical chorioamnionitis than predicting positive amniotic fluid culture results. Gestational age-dependent normal ranges and pathologic conditions that may alter amniotic fluid glucose concentrations should be considered when interpreting amniotic fluid glucose values to diagnose microbial invasion of the amniotic cavity.

Physiology of uterine activity in pregnancy

During the past few years enormous progress has been made in the understanding of the molecular mechanisms involved in parturition; however, the answer to the fundamental question of how labor is initiated remains elusive. This is a very important question because alterations in the timing of birth (preterm and post-term deliveries) are associated with much of perinatal morbidity and mortality. Currently available treatments for preterm labor are not clearly effective. Prevention of preterm delivery by home uterine monitoring has been proposed; however, the value of this technique has not been conclusively shown. A variety of substances have been implicated in the genesis of labor, including oxytocin, prostaglandins, cytokines, and endothelin. The role of infection in preterm labor has also been extensively studied, but it seems clear that a relatively small percentage of preterm labor is caused by infection. Attention has also focused on the role of estrogen and progesterone, and the possible uses of progesterone antagonists in the induction of labor. A better understanding of the relationship of intrauterine hypoxia and preterm delivery may also help us in establishing treatment and prevention strategies.

Evidence of participation of the soluble tumor necrosis factor receptor I in the host response to intrauterine infection in preterm labor.

This study was conducted to determine whether: (1) the soluble tumor necrosis factor receptor I (sTNF-rI) is present in human amniotic fluid, neonatal urine, and the feto-maternal plasma; (2) there are changes in the concentration of the sTNF-rI in amniotic fluid with gestational age; and (3) microbial invasion of the amniotic cavity (in term and preterm parturition) is associated with changes in amniotic fluid sTNF-rI concentrations. Amniotic fluid was retrieved by amniocentesis from 185 women classified into 11 groups according to gestational age (midtrimester, preterm gestation, and term), the presence or absence of labor, spontaneous rupture of membranes and microbial invasion of the amniotic cavity. sTNF-rI was assayed with a sensitive and enzyme-linked immunosorbent assay (ELISA) validated for amniotic fluid. In addition, sTNF-rI concentrations were determined in fetal blood obtained by cordocentesis in preterm gestations (N = 24) or at the time of delivery after spontaneous labor at term (N = 10). sTNF-rI concentrations were also measured in maternal venous and cord blood and neonatal urine (n = 13). sTNF-rI was found to be present in all amniotic fluid samples, maternal blood and fetal blood and neonatal urine samples; sTNF-rI concentrations were higher in the midtrimester than at term (mean +/- SD: 36.2 +/- 12.2 ng/ml versus mean +/- SD: 5.56 +/- 5.72 ng/ml [P < .05]); patients with preterm labor and microbial invasion of the amniotic cavity (with intact or with ruptured membranes) had significantly higher amniotic fluid concentrations of sTNF-rI than patients without microbial invasion; in the absence of microbial invasion, parturition (both term and preterm) was not associated with changes in amniotic fluid concentrations of sTNF-rI; neonatal urine contained the highest concentrations of sTNF-rI of all biological fluids assayed including maternal and neonatal/fetal blood and amniotic fluid. It was concluded that sTNF-rI is a physiologic constituent of amniotic fluid, as well as of the fetal and maternal plasma; that amniotic fluid sTNF-rI concentrations decrease as a function of gestional age and increases in the concentration of the sTNF-rI are part of the host response to intrauterine infection in preterm parturition.

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

International Journal of Gynecology & ObstetricsVolume 35, Issue 3 p. 289-289 Citations from the literature diseases in pregnancy Amniotic fluid glucose concentration: A rapid and simple method for the detection of intraamniotic infection in preterm labor R Romero, R RomeroSearch for more papers by this authorC Jimenez, C JimenezSearch for more papers by this authorAK Lohda, AK LohdaSearch for more papers by this authorJ Nores, J NoresSearch for more papers by this authorS Hanaoka, S HanaokaSearch for more papers by this authorC Avila, C AvilaSearch for more papers by this authorR Callahan, R CallahanSearch for more papers by this authorM Mazor, M MazorSearch for more papers by this authorJC Hobbins, JC HobbinsSearch for more papers by this authorMP Diamond, MP DiamondSearch for more papers by this author R Romero, R RomeroSearch for more papers by this authorC Jimenez, C JimenezSearch for more papers by this authorAK Lohda, AK LohdaSearch for more papers by this authorJ Nores, J NoresSearch for more papers by this authorS Hanaoka, S HanaokaSearch for more papers by this authorC Avila, C AvilaSearch for more papers by this authorR Callahan, R CallahanSearch for more papers by this authorM Mazor, M MazorSearch for more papers by this authorJC Hobbins, JC HobbinsSearch for more papers by this authorMP Diamond, MP DiamondSearch for more papers by this author First published: July 1991 https://doi.org/10.1016/0020-7292(91)90332-YCitations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume35, Issue3July 1991Pages 289-289 RelatedInformation

185 Amniotic fluid glucose as a predictor of intraamniotic infection in preterm labor and preterm rupture of membranes

185 Amniotic fluid glucose as a predictor of intraamniotic infection in preterm labor and preterm rupture of membranes

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 < 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.

C-reactive protein in preterm labour: association with outcome of tocolysis and placental histology.

Tocolytics were administered in 66 consecutive women in uncomplicated preterm labour with intact fetal membranes (53 singleton and 13 twin pregnancies). C-reactive protein (CRP), a marker of infection, was determined daily and used retrospectively to investigate the role of subclinical infection in preterm labour and to predict the efficacy of tocolysis and the development of a clinical perinatal infection. CRP was also determined in 66 women in uncomplicated labour at term (53 singleton and 13 twin pregnancies). The placenta was examined for histological evidence of infection in all patients who were delivered before 36 weeks (n = 21) and in all women in the control group (n = 66). Elevated CRP levels were more often found in patients who were refractory to tocolysis, suggesting an underlying infectious morbidity. Placental infection was found in 62% of the preterm delivery group and in 12% of the control group. There was an association between elevated CRP levels and histological evidence of placental infection. However, confounding factors such as urinary tract infections limit the usefulness of the CRP test. Because CRP cannot predict clinical perinatal infection accurately, its clinical relevance is very limited.

The association of subclinical infection with preterm labor: The role of C-reactive protein

The role of subclinical intrauterine infection in preterm labor was evaluated prospectively in 40 patients and appropriate control subjects. The 24 preterm labor patients (60%) with a negative C-reactive protein value responded to tocolysis 95.8% of the time, with a mean delay of delivery of 35.5 days and a mean gestational age of 36.9 weeks. The 16 patients (40%) with a positive C-reactive protein value responded to tocolysis only 37.5% of the time, with a mean delay of delivery of 14.4 days and a mean gestational age of 33.2 weeks. Pathologic evidence of chorioamnionitis was present in 32.9% of 310 preterm deliveries as compared to only 22.3% of 1631 term deliveries. The presence of subclinical infection must be considered in cases of preterm labor, especially among patients for whom tocolytic therapy is unsuccessful.