Independent Predictor Of Preterm Delivery Research Articles

The evaluation of maternal systemic thiol/disulphide homeostasis for the short-term prediction of preterm birth in women with threatened preterm labour: a pilot study

The aim of this study was to investigate maternal systemic thiol/disulphide homeostasis (TDH) for the short-term prediction of preterm birth in women with threatened preterm labour (TPL). This prospective study included 75 pregnant women whose pregnancies were complicated by TPL. Thirty-seven of them delivered within 7 days and 38 of them delivered beyond 7 days. Maternal serum samples were collected at the day of diagnosis and the TDH was measured. The maternal disulphide level was significantly higher in pregnant women who delivered within 7 days (25.0 ± 9.8 μmol/L vs 19.4 ± 9.8 μmol/L, p: .015). The threshold value of 22.1 μmol/L for maternal disulphide level predicted delivery within 7 days with 62.2% sensitivity and 60.5% specificity (area under curve 0.651, confidence interval 0.53–0.78). The likelihood ratios for short cervix (≤25 mm) and maternal disulphide level (≥22 μmol/L) to predict delivery within 7 days was found to be 8.7 and 7.3, respectively. The likelihood ratio of combining two tests to predict delivery within 7 days was found to be 11.4. The maternal TDH, which is an indicator of oxidative stress status in maternal compartment, is disturbed in TPL cases who delivered within 7 days. Elevated maternal disulphide level along with cervical length screening predicts a short latency period in pregnancies with TPL. IMPACT STATEMENT What is already known on this subject? Spontaneous preterm delivery is one of the major complication of pregnancy and the common cause of neonatal morbidity and mortality. Threatened preterm labour (TPL) is also a frequent complaint in obstetric emergency care units in all around the world. Triaging women with TPL is mandatory for planning further management therapies, since the most of them will eventually deliver at term. Only the measurement of cervical length in symptomatic women has moderate accuracy in predicting preterm delivery. Short cervix is described as an independent predictor of preterm delivery in women with TPL, its predictive accuracy as a single measurement is relatively limited. On this account, several potential markers like foetal fibronectin in the cervicovaginal fluid, salivary oestriol, prolactin in vaginal discharge, maternal serum calponin and interleukin-6 in the amniotic fluid were examined to predict preterm delivery in previous studies. However, none of them represented an excessive predictive accuracy like high sensitivity, PPV or NPV. What do the results of this study add? We report a method which has higher diagnostic and predictive performance to identifying TPL women with high risk of preterm delivery. According to the current literature, there are accumulated data about the correlation between oxidative stress (OS) and preterm delivery regardless of the amniotic membrane status. However, it is still debated whether OS is a trigger or a consequence of preterm delivery. Our study provides evidence for the first time that maternal serum thiol/disulphide homeostasis, which is an indicator of OS in maternal compartment, is disturbed in TPL cases who delivered within 7 days. The high disulphide level in maternal serum, along with cervical length measurement (short cervix) accurately predicts a short latency period in TPL cases. What are the implications of these findings for clinical practice and/or further research? This novel test combination (maternal serum disulphide level and cervical length measurement) could be used clinically to triage pregnant women presenting with TPL, avoiding overtreatment, unnecessary hospitalisations and increased medical costs. The future research would be addressed on reducing maternal OS by using new antioxidant treatment strategies to improve perinatal and long-term childhood outcomes.

Effect of Dipping Pattern of Gestational Hypertension on Maternal Symptoms and Physical Findings, Birth Weight and Preterm Delivery

SUMMARYThe study aimed to determine if the non-dipping pattern of blood pressure (BP) influences preterm delivery in gestational hypertension (GH), but also maternal clinical findings and birth weight. Sixty women with GH, i.e. 30 women with a dipping BP profile (control group) and 30 non-dippers (study group), were included in the study. Echocardiography was performed in all subjects, as well as ambulatory blood pressure monitoring (ABPM) during third trimester. ABPM was repeated 6-8 weeks after delivery. Thirteen women with preterm delivery were classified as non-dippers and only four as dippers (p=0.01). The average and peak systolic and diastolic night-time BP had negative linear correlation with birth weight (p<0.0005). Total vascular resistance (p<0.0005) and mass index (p=0.014) were significantly higher as compared with women with term delivery, while ejection fraction (EF) (p=0.007) and circumferential systolic velocity (p=0.042) were significantly reduced in the preterm delivery group. Multivariate binary logistic regression identified the average night-time systolic BP, left ventricular mass index and EF as independent predictors of preterm delivery. Study results suggested a relationship of the non-dipping BP pattern in GH with preterm delivery, birth weight, and maternal clinical findings.

A new marker in preterm labor: RDW and MPV

Aim: To evaluate whether serum platelets Mean Platelet Volum (MPV), and Red Cell Distribution width (RDW) are useful as predictors of preterm labour (PL) in patients with preterm labour (PL), and to compare the clinical efficacy of various serum inflammatory markers to predict the risk of preterm delivery (PD). Materials, and methods: The main group consisted of pregnant women who were earlier than the 37th gestational week. The control group has consisted of pregnant bigger than 37th weeks of gestation. The patients with PL who participated in the study group were divided into early preterm labour (EPL), and late preterm labour (LPL) groups. The two groups were investigated in terms of clinical aspects of RDW, and MPV and serum markers studied at admission. ROC curve analysis was used to determine the optimal MPV, RDW cut-off levels predicting PL. Results: Neutrophil (NEU), MPW, RDW, and neutrophil to lymphocyte ratio (NLR) were significantly higher in LPL than in women who gave birth at term (p=0.006, OR=1.411; p&lt;0.001, OR=1.410; 0.002, OR=1.612, p=0.035, OR=1.294). In multivariate regression analysis, MPV positive was the strongest predictor variable. Besides, there was a significant correlation between MPV and RDW elevation, and neonatal intensive care needs (NICU) in women who delivered between 34 weeks, and 37 weeks. Conclusion: High RDW and MPV are independent predictors of preterm delivery in patients with LPL. In our study, we found that the increase of RDW and MPV was higher in women with high PL risk more than in healthy individuals. MPV has the highest area for prediction of preterm birth, and RDW&gt;14,5, and MPV&gt;9,6 have the highest sensitivity and specificity. RDW may be more significant than measuring any of the individual markers in the simultaneous use of preterm delivery. The simultaneous use of RDW and MPV with existing markers to increase our identifying abilities of preterm labour may be stronger than that of any of the individual markers.

Evaluation of the correlation between IL-1β, IL-8, IFN-γ cytokine concentration in cervico-vaginal fluid and the risk of preterm delivery

The aim of the study was to evaluate IL-1β, II-8, IFN-γ cytokine concentrations in cervico-vaginal fluid in patients with threatening preterm delivery. The study group included 84 patients between 27 and 34 weeks of pregnancy admitted with symptoms of threatened preterm delivery. The cervico-vaginal fluid was taken from each patient qualified for the study and IL-1β, II-8, IFN-γ concentration was analyzed by enzyme-linked immunosorbent assay (ELISA). The following factors were analyzed: maternal age and parity gestational age at admission for the examination and at delivery, sex of the newborn, Apgar evaluation at 1 and 5 minutes of life, umbilical blood pH, history of miscarriage or preterm delivery pre-pregnancy body mass index, and smoking. Their influence on the concentration of biochemical markers tested in patients at risk of preterm delivery was investigated. In the study group, patients who delivered preterm had significantly higher concentrations of IL-1β and II-8 as compared to patients who delivered at term. Patients who delivered preterm more often had a history of a miscarriage and their newborns had lower birth weight, lower Apgar score, and lower pH of the umbilical blood. As far as factors significantly influencing cytokine concentrations are concerned, the level of IL-1β and II-8 concentration is an independent predictor of preterm delivery in patients with threatened preterm labor. In the study group, the IFN-γ concentration did not significantly diversify patients who delivered preterm and at term.

The unborn smoker: association between smoking during pregnancy and adverse perinatal outcomes.

To evaluate a possible dose-response relationship between active maternal smoking during pregnancy and adverse perinatal outcome. Retrospective cohort study. Population-based in Montreal, Quebec, Canada. Women who gave birth to a liveborn or stillborn infant during the period of January 2001 to December 2007. Active smokers of different daily cigarette consumption (n=1646) were identified through maternal self-reporting. The reference group comprised 19,292 non-smoking women who delivered during the same period. Birth weight, preterm delivery rate, fetal and neonatal mortality and morbidity, and congenital malformations. Preterm delivery rate was significantly higher in the smoking group compared with controls (22.2% vs. 12.4%, P<0.05), as was intrauterine fetal demise (1.4% vs. 0.3%, P<0.05). Newborns of active smokers were more likely to weigh less (3150±759 g vs. 3377±604 g, P<0.05), suffer from respiratory distress syndrome (2.5% vs. 1.3%, P<0.05), suffer from a cardiac malformation (1.5% vs. 0.8%, P<0.05), and die (neonatal death 1.2% vs. 0.6%, P<0.05). A dose-response relationship was demonstrated between levels of daily cigarette smoking and several adverse outcomes. Using multiple regression models, smoking was found to be an independent predictor of preterm delivery (odds ratios (OR) 1.9, 95% confidence intervals (95%CI) 1.6-2), and intrauterine fetal demise (OR 2.4, 95%CI 1.4-4.2). Any amount of daily smoking appears to harm the fetus and newborn. As pregnancy may be a "window of opportunity" for behavioural changes, efforts to promote smoking cessation should be encouraged.

Predictive Value of Cervical Length in Women With Threatened Preterm Labor

To assess the predictive role of ultrasonographic cervical length for preterm delivery in women with threatened preterm labor. A retrospective cohort study of women with singleton pregnancies who presented with preterm labor before 34 weeks of gestation and underwent ultrasonographic measurement of cervical length in a tertiary medical center. Women with cervical cerclage, cervical dilatation greater than 3 cm at presentation, and pregnancies complicated by placental abruption, clinical chorioamnionitis, stillbirth, or major fetal anomalies were excluded. The predictive accuracy of cervical length for preterm delivery was analyzed using both fixed thresholds and outcome-specific thresholds, which are associated with a detection rate of 90%, false-positive rate of 10%, or the inflexion point of the receiver operator characteristic curve. Between 2007 and 2012, 1,077 women presented with preterm labor and met the study criteria. The correlation between cervical length and the time interval to delivery was significant but weak (r=0.293, P<.001). Cervical length was independently associated with the risk of preterm delivery at less than 37, 35, and 32 weeks of gestation and within 14 and 7 days from presentation (a 4-7% decrease in the risk for each additional millimeter of cervical length) as well as with the time interval between presentation and delivery (each additional 2 mm was associated with an increase of 1 day). Overall, the accuracy of cervical length in predicting preterm delivery was relatively poor. Although cervical length is an independent predictor of preterm delivery in women with preterm labor, its predictive accuracy as a single measure is relatively limited. : II.

Early pregnancy vaginal fluid phosphorylated insulin‐like growth factor binding protein‐1 predicts preterm delivery

We aimed to study vaginal fluid phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1) testing in early pregnancy to predict spontaneous preterm delivery (PTD). Vaginal and cervical swab samples were collected from 5180 unselected women during the first-trimester (mean gestational age 13.1 weeks) ultrasound screening. PhIGFBP-1 was measured in vaginal and cervical fluid by an immunoenzymometric assay. Concentrations of ≥10 µg/L were considered elevated. The outcome measure was spontaneous PTD at <32 or <37 weeks gestation. The median concentrations of first-trimester vaginal and cervical phIGFBP-1 were higher in women with spontaneous PTD at <32 and <37 weeks gestation. When 10 µg/L of phIGFBP-1 was used as a cut-off level, the OR in predicting PTD at <32 weeks gestation was 8.6 (95% CI 3.6-20.7) for vaginal samples and 3.6 (95% CI 1.7-7.9) for cervical samples. At <37 weeks gestation, the OR in predicting PTD was 3.0 (95% CI 1.9-3.9) for vaginal samples and 1.9 (95% CI 1.4-2.5) for cervical samples. In multiple logistic regression analysis, both elevated vaginal and cervical fluid phIGFBP-1 levels were independent predictors of PTD both at <32 and <37 weeks gestation. First-trimester vaginal phIGFBP-1 performed better than cervical phIGFBP-1 in the prediction of spontaneous PTD.

Increased urinary orosomucoid excretion predicts preeclampsia in pregnant women with pregestational type 1 diabetes

Aims We evaluated the urinary orosomucoid excretion (UOE) as a biomarker of preeclampsia and preterm delivery in pregnant women with type 1 diabetes. Methods Singleton pregnant women with pregestational type 1 diabetes were included provided one urine sample had been collected before 17 gestational weeks. Serum and urinary orosomucoid were analysed by immunoturbidimetry. Primary outcome measurements were development of preeclampsia (blood pressure > 140/90 mmHg and proteinuria) and preterm delivery before 37 weeks. Results In total 173 women were included. The UOE increased during pregnancy. Preeclampsia developed in 20 women and 65 women delivered preterm. Using logistic regression analysis we found that UOE > 1.37 mg/l (OR: 6.85 (95% CI: 1.97–23.88; p < 0.003)), nulliparity (3.88 (1.10–13.72); p < 0.04), systolic blood pressure > 120 mmHg (4.12 (1.35–12.59); p < 0.02) and duration of diabetes > 20 years (3.69 (1.18–11.52); p < 0.03) independently predicted the development of preeclampsia. Independent predictors of preterm delivery were duration of diabetes and HbA1c > 7%. The remaining covariates included in the regression models were BMI, serum creatinine, smoking and microalbuminuria. Conclusions Increased UOE early in pregnancy predicted preeclampsia in women with pregestational type 1 diabetes independently of albuminuria and other known risk factors. No association to preterm delivery was found.

Treatment with Protease Inhibitors and Coinfection with Hepatitis C Virus Are Independent Predictors of Preterm Delivery in HIV‐Infected Pregnant Women

Treatment with Protease Inhibitors and Coinfection with Hepatitis C Virus Are Independent Predictors of Preterm Delivery in HIV‐Infected Pregnant Women

Evaluation and validation of a new risk score (CLEOPATRA score) to predict the probability of premature delivery for patients with threatened preterm labor

To develop a clinically useful tool to predict the probability of preterm delivery in patients with threatened preterm labor. One hundred and seventy patients with preterm labor between 24 and 34 weeks of gestation were included. Preterm delivery < 37 weeks of gestation was the main endpoint of the study. The data were randomized and split into an evaluation set (n = 85) and a validation set (n = 85). The evaluation set was subjected to stepwise backward logistic regression analysis to quantify the relative impact of four potential risk factors, including individual patient factors, results of a rapid fetal fibronectin assay, and sonographic measurement of cervical length. Using the constant of the logistic regression analysis and the beta-coefficients for the identified risk factors the individual probability of preterm delivery for each woman of the validation dataset was calculated. The area under a receiver-operating characteristics curve (AUC) was used to evaluate the discriminating power of the score. The overall rate of preterm delivery was 27.1%. The logistic regression analysis was performed for the potential predictors of spontaneous preterm delivery, identified by univariate analysis. These were positive fetal fibronectin, cervical length, previous preterm delivery and maternal age. Two risk factors were independent predictors of preterm delivery and were included in the CLEOPATRA I (clinical evaluation of preterm delivery and theoretical risk assessment) score: cervical length measurement and previous preterm delivery were associated with a higher risk of preterm delivery (odds ratio, 7.65 and 6.74, respectively). Since fetal fibronectin assay is not available at all institutions worldwide, it was excluded from the initial model. In the CLEOPATRA II model the risk factors fetal fibronectin and previous preterm delivery were associated with higher risk of preterm delivery, with odds ratios of 17.9 and 4.56, respectively. The discrimination power (AUC) obtained from the models were: CLEOPATRA I, 0.69 (95% CI, 0.56-0.82); CLEOPATRA II, 0.81 (95% CI, 0.69-0.93). In symptomatic women the risk for preterm delivery can be predicted best with the CLEOPATRA II score based on fetal fibronectin and previous preterm delivery.

A prospective study of vaginal pH as a predictor of preterm delivery

Objective: To test the usefulness of vaginal pH determinations in the prediction of the risk of preterm delivery at or before 36 weeks of gestation. Methods: This was a prospective study of asymptomatic pregnant women. Vaginal pH was determined using pH paper in a sterile speculum examination during prenatal visits. Patients were followed to delivery and hospital records were reviewed to extract obstetric information. A total of 308 women agreed to participate and met the criteria for enrolment. Preterm delivery was defined as delivery at or prior to 36 weeks of gestation. Abnormal pH was defined as a pH of > 5.0. Results: Abnormal vaginal pH was associated with increased risk of preterm delivery, (OR 3.3, 95% CI 1.15, 9.2; p = 0.02). In the first trimester, an abnormal vaginal pH was not associated with preterm delivery (p = 0.3). After the first trimester, a vaginal pH of 5.0 or greater was associated with increased risk of preterm delivery (OR 9.6, 95% CI 2.0, 45.5; p = 0.001) as well as delivering an infant of less than 2500 g (OR 3.1, 95% CI 1.2, 7.8; p = 0.015). History of a previous preterm delivery was associated with increased risk of preterm delivery (OR 6.2, 95% CI 1.6, 23.7; p = 0.02). A logistic regression model used to control for a history of preterm delivery and race showed abnormal vaginal pH to remain as an independent predictor of preterm delivery (p = 0.01). Conclusions: High vaginal pH (≥ 5.0) identified women at risk for preterm delivery.

A prospective study of vaginal pH as a predictor of preterm delivery

Objective: To test the usefulness of vaginal pH determinations in the prediction of the risk of preterm delivery at or before 36 weeks of gestation.Methods: This was a prospective studyof asymptomatic pregnant women. Vaginal pH was determined using pH paper in a sterile speculum examination during prenatal visits. Patients were followed to delivery and hospital records were reviewed toextract obstetric information. A total of 308 women agreed to participate and met the criteria for enrolment. Preterm delivery was defined as delivery at or prior to 36 weeks of gestation. Abnormal pH wasdefined as a pH of > 5.0.Results: Abnormal vaginal pH was associated with increased risk of preterm delivery, (OR 3.3, 95% CI 1.15, 9.2; p = 0.02). In the first trimester, an abnormalvaginal pH was not associated with preterm delivery (p = 0.3). After the first trimester, a vaginal pH of 5.0 or greater was associated with increased risk of preterm delivery (OR 9.6, 95% CI 2.0,45.5; p = 0.001) as well as delivering an infant of less than 2500 g (OR 3.1, 95% CI 1.2, 7.8; p = 0.015). History of a previous preterm delivery was associated with increased risk of pretermdelivery (OR 6.2, 95% CI 1.6, 23.7; p = 0.02). A logistic regression model used to control for a history of preterm delivery and race showed abnormal vaginal pH to remain as an independent predictorof preterm delivery (p = 0.01).Conclusions: High vaginal pH (≥ 5.0) identified women at risk for preterm delivery.

Transvaginal Ultrasound in the Prediction of Preterm Delivery: Singleton and Twin Gestations

Objective: To compare, in singleton and twin pregnancies, the effectiveness of transvaginal ultrasound versus digital examination in predicting preterm delivery in women with suspected preterm labor.Methods: Transvaginal ultrasound and pelvic examinations were performed on patients admitted with suspected preterm labor between 23 and 33 weeks’ gestation. Ultrasound assessment of cervical length and the presence of funneling with fundal pressure were recorded for each patient, and the results were compared with dilatation and effacement as assessed by digital examination for the prediction of preterm delivery in the two groups (singletons and twins).Results: One hundred sixty-two subjects were recruited (136 singletons and 26 twin pregnancies), with no significant demographic differences between the groups. Overall, 33% of the participants delivered preterm (27% of singletons, 62% of twins). Using receiver operating characteristic curves, the best cutoff points were 30 mm for endocervical length at ultrasound, 50% for effacement, and 1.5 cm for dilatation. Of these, the best predictor was endocervical length, which was a better predictor in singleton than in twin pregnancies. Of the potential predictors, including endocervical length, funneling, dilatation, and effacement, only endocervical length was an independent predictor of preterm delivery at less than 34 weeks’ gestation for both singletons and twins by multiple logistic regression. When analyzed for delivery at less than 37 weeks’ gestation, this relation held true for singletons but not twins. Endocervical length less than 30 mm had a sensitivity of 81% and 75%, specificity of 65% and 30%, positive predictive value of 46% and 63%, and negative predictive value of 90% and 43% for singleton and twin pregnancies, respectively, in predicting spontaneous birth at less than 37 weeks’ gestation.Conclusion: Between 23 and 33 weeks’ gestation, transvaginal ultrasound assessment of endocervical length is superior to funneling and digital examination in predicting preterm delivery in patients who present with suspected preterm labor, and is a better predictor in singletons than in twins.

Evaluation of a rapid strip test for insulin-like growth factor binding protein-1 in the diagnosis of ruptured fetal membranes

We evaluated the clinical usefulness of a new bedside test (PROM TEST) for insulin-like growth factor binding protein-1 (IGFBP-1) in the detection of ruptured fetal membranes (ROM). Cervicovaginal secretion was sampled between 15 and 37 weeks of gestation from asymptomatic women with apparently intact membranes and from women with clinically confirmed ROM, as well as from symptomatic women with suspected ROM based on history. IGFBP-1 in samples was detected with a dipstick based on immunochromatography. The test result was positive in 100% of cases with unequivocal ROM and in 5.3% of cases with apparently intact membranes. Furthermore, the PROM TEST was positive in 64 of 181 patients evaluated for suspected ROM based on history, but in whom the diagnosis could not be clinically confirmed at the initial evaluation. Fifty of the 64 women (78.1%) were delivered prematurely (< 37 weeks). Five of the 117 PROM-negative patients had elective cesarean section for reasons unrelated to ROM before 37 weeks and 10 of the remaining 112 patients (8.9%) had preterm delivery. Women with equivocal ROM and a positive test result had a 6.9-fold increased relative risk (95% confidence interval 4.2–11.4) of preterm delivery compared with women who had a negative result at the time of evaluation. Multiple logistic regression including PROM TEST result, contractions, vaginal bleeding and cervical changes indicated that a positive PROM TEST result was an independent predictor of preterm delivery ( P = 0.0001). In summary, a positive PROM TEST result identifies ROM with high sensitivity and a negative result effectively excludes those with intact membranes. In patients with suspected but clinically unconfirmed ROM, the positive test result is associated with increased risk of preterm delivery, suggesting that microruptures of fetal membranes can also be detected by the PROM TEST.

Increased interleukin-6 concentrations in cervical secretions are associated with preterm delivery

This study sought to determine whether elevated concentrations of interleukin-6 in the cervical and vaginal secretions of patients between 24 and 36 weeks' gestation predicted subsequent preterm delivery and/or identified those preterm deliveries associated with maternal infectious morbidity. A cohort study was undertaken with cervical and vaginal samples collected from 161 consenting patients seen at 3- to 4-week intervals between 24 and 36 weeks. Levels of interleukin-6 were measured by immunoassay. Demographic, obstetric, neonatal, and laboratory data were analyzed by Fisher's exact test, Student t test, or Wilcoxon rank sum test, linear and multiple logistic regression, and receiver-operator characteristic curve analysis. There were 4.2-fold and 3.4-fold increases in maximal cervical and vaginal interleukin-6 concentrations, respectively, among patients with preterm deliveries versus term deliveries. The receiver-operator characteristics curve analysis indicated that a single cervical interleukin-6 value > 250 pg/ml of sample buffer, present between 24 and 36 weeks' gestation, optimally identified patients with subsequent preterm deliveries versus term deliveries (sensitivity 50.0%, 95% confidence interval 33.2% to 66.8%; specificity 85.0%, 95% confidence interval 78.8% to 91.2%; positive predictive value 47.2%, 95% confidence interval 30.9% to 63.5%; negative predictive value 86.4%, 95% confidence interval 80.4% to 92.4%). The optimal vaginal interleukin-6 cutoff value (> 125 pg/ml) proved less sensitive (45.5%, 95% confidence interval 28.5% to 62.4%) but equally specific (86.6%, 95% confidence interval 80.7% to 92.5%). Multiple logistic regression indicated that a cervical interleukin-6 level > 250 pg/ml was an independent predictor of preterm delivery (adjusted odds ratio 4.8, 95% confidence interval 1.7 to 14.3). Cervical interleukin-6 levels did not correlate with cervical change or gestational age at sampling. Among patients delivered preterm there were no differences in the mean white blood cell count on admission or the prevalence of vaginal pathogens, alkaline vaginal pH, chorioamnionitis, or endometritis among patients with cervical interleukin-6 values > 150 or < or = 250 pg/ml. Cervical interleukin-6 is a relatively insensitive, although fairly specific discriminator of patients with subsequent preterm deliveries. Among patients delivered preterm, elevated cervical interleukin-6 values are not apparently associated with maternal infectious morbidity.

The presence of cervical and vaginal fetal fibronectin predicts preterm delivery in an inner-city obstetric population

It has previously been shown that fibronectin bearing a specific oncofetal domain is present at the chorionic-decidual interface and that its release into cervical and vaginal secretions accurately predicts preterm delivery in patients with uterine contractions. This study examines whether serial assessment of cervical and vaginal fetal fibronectin allows for the prediction of preterm delivery in symptom-free patients derived from an inner-city, general obstetric population. Cervical and vaginal samples were obtained from 429 consenting patients who received routine prenatal care between 24 and 37 weeks' gestation. A sensitive immunoassay was used to quantitate cervical and vaginal fetal fibronectin levels, and clinicians were blinded to fetal fibronectin results. Post hoc receiver operating characteristic curve analysis was used to determine which sample site (cervical or vaginal), fetal fibronectin concentration, and number of consecutive positive samples optimized screening efficacy. Logistic regression was employed to determine whether fetal fibronectin was an independent predictor of preterm delivery. The spontaneous preterm delivery rate was 11% (49/429). Among the 326 patients sampled within 28 days of delivery, receiver operating characteristic curve analysis indicated that the presence of a single cervical fetal fibronectin value > 60 ng/ml between 24 and 36 weeks' gestation predicted preterm delivery with a sensitivity of 73%, a specificity of 72%, and positive and negative predictive values of 25% and 95%, respectively. A vaginal fetal fibronectin value > 50 ng/ml predicted preterm delivery with a sensitivity of 68%, a specificity of 80%, and positive and negative predictive values of 30% and 95%, respectively. Cervical and vaginal fetal fibronectin predicted preterm deliveries resulting from both membrane rupture and preterm labor with intact membranes. A positive fetal fibronectin result preceded preterm delivery by 3.4 (+/- 3.2) weeks. Stepwise logistic regression demonstrated that cervical and vaginal fetal fibronectin levels were independent predictors of preterm delivery with adjusted odds ratios of 8.9 (95% confidence interval 3.6 to 22.1) and 6.0 (95% confidence interval 2.6 to 13.7), respectively. Among patients undergoing monthly cervical and vaginal sampling between 24 and 36 weeks' gestation, the presence of fetal fibronectin is a sensitive and specific predictor of preterm delivery.

Amniotic fluid interleukin-6 determinations are of diagnostic and prognostic value in preterm labor.

The purpose of this study was to determine if amniotic fluid concentrations of the interleukin-6 (IL-6) are of value in diagnosis of microbial invasion of the amniotic cavity and in the prediction of failure of tocolysis, preterm delivery and perinatal morbidity and mortality. Amniotic fluid was obtained by transabdominal amniocentesis from 146 consecutive patients admitted with the diagnosis of preterm labor and intact membranes. Fluid was cultured for aerobic and anaerobic bacteria as well as for mycoplasmas. Amniotic fluid IL-6 levels were measured using a monoclonal antibody-based enzyme-linked immunosorbent assay with a sensitivity of 0.03 ng/ml. Logistic regression and Cox's proportional hazards model were used to examine the effect of several variables on dichotomous outcomes or interval to delivery. Patients with a positive amniotic fluid culture had a significantly higher amniotic fluid IL-6 concentrations than patients with a negative culture (median 91.2 ng/ml, range 0.9 to 437 ng/ml versus median 0.4 ng/ml, range < 0.3 to 195 ng/ml, respectively; P < .0001). An amniotic fluid IL-6 concentration of greater than or equal to 11.3 ng/ml had a sensitivity of 93.3% (14 of 15) and a specificity of 91.6% (120 of 131). All patients with an amniotic fluid IL-6 concentration above 11.3 ng/ml and a negative amniotic fluid culture (N = 11) delivered preterm and all placenta available for examination (N = 7) had histologic evidence of chorioamnionitis. Amniotic fluid concentrations of IL-6 were an independent predictor of preterm delivery, amniocentesis-to-delivery interval and neonatal morbidity and mortality. Moreover, IL-6 concentrations added significant information to the prediction of these outcomes to that provided only by clinical information such as cervical dilatation, gestational age at admission or at delivery. IL-6 is a sensitive and rapid test for the detection of microbial invasion of the amniotic cavity and for identifying women at risk for spontaneous preterm delivery and neonates at risk for morbidity and mortality.