Upregulated amniotic fluid cytokines and chemokines in emergency cerclage with protruding membranes

Rescue Cerclage in Women With Acute Cervical Insufficiency and Intra-Amniotic Inflammation: A Retrospective Cohort Study

BACKGROUND

To assess the effectiveness of rescue cerclage concerning pregnancy and neonatal outcomes in women with acute cervical insufficiency (CI) complicated with intra-amniotic inflammation (IAI) compared with those managed expectantly.

METHODS

This retrospective cohort study included 87 consecutive singleton pregnant women (17-25 weeks) with acute CI who underwent amniocentesis to assess IAI. Amniotic fluid (AF) samples were assayed for interleukin-6 to define IAI (≥ 2.6 ng/mL). Primary and secondary outcomes were assessed in a subset of CI patients with IAI. The primary outcome measures were spontaneous preterm birth (SPTB) at < 28 and < 34 weeks, and the secondary outcomes were interval from sampling to delivery, neonatal survival, neonatal birth weight, and histologic and clinical chorioamnionitis. Macrolide antibiotics were prescribed depending on the type of microorganism isolated from the AF, clinically suspected IAI, and the discretion of the attending clinician.

RESULTS

IAI was identified in 65.5% (57/87) of patients with CI, of whom 73.6% (42/57) were treated with macrolide antibiotics. Among the CI patients with IAI (n = 57), 40 underwent rescue cerclage and 17 were expectantly managed. The rates of SPTBs at < 28 and < 34 weeks were significantly lower and the latency period was significantly longer in the cerclage group than in the group that was managed expectantly. The median birth weight and neonatal survival rate were significantly higher in the cerclage group than in the group that was managed expectantly. However, the rates of histologic and clinical chorioamnionitis did not differ between the groups. Multivariable analyses revealed that rescue cerclage placement and administration of macrolide antibiotics were significantly associated with a decrease in SPTBs at < 28 and < 34 weeks, prolonged gestational latency, and increased likelihood of neonatal survival, after adjusting for possible confounding parameters; however, macrolide antibiotic administration did not reach statistical significance with respect to SPTB at < 34 weeks and neonatal survival (P = 0.076 and 0.063, respectively).

CONCLUSION

Rescue cerclage along with macrolide antibiotic treatment may positively impact pregnancy and neonatal outcomes in women with CI complicated by IAI, compared with expectant management. These findings suggest the benefit of cerclage placement even in patients with CI complicated by IAI.

Development and validation of models for predicting preterm birth and gestational latency following emergency cervical cerclage: A multicenter cohort study

INTRODUCTION

Emergency cervical cerclage is a recognized method for preventing mid-trimester pregnancy loss and premature birth; however, its benefits remain controversial. This study aimed to establish preoperative models predicting preterm birth and gestational latency following emergency cervical cerclage in singleton pregnant patients with a high risk of preterm birth.

MATERIAL AND METHODS

We retrospectively reviewed data from patients who received emergency cerclage between 2015 and 2023 in three institutions. Patients were grouped into a derivation cohort (n = 141) and an independent validation cohort (n = 61). Univariate and multivariate logistic and Cox regression analyses were used to identify independent predictive variables and establish the models. Harrell's C-index, time-dependent receiver operating characteristic curves and areas under the curves, calibration curve, and decision curve analyses were performed to assess the models.

RESULTS

The models incorporated gestational weeks at cerclage placement, history of prior second-trimester loss and/or preterm birth, cervical dilation, and preoperative C-reactive protein level. The C-index of the model for predicting preterm birth before 28 weeks was 0.87 (95% CI: 0.82-0.93) in the derivation cohort and 0.82 (95% CI: 0.71-0.92) in the independent validation cohort; The C-index of the model for predicting gestational latency was 0.70 (95% CI: 0.66-0.75) and 0.78 (95% CI: 0.71-0.84), respectively. In the derivation set, the areas under the curves were 0.84, 0.81, and 0.84 for predicting 1-, 3- and 5-week pregnancy prolongation, respectively. The corresponding values for the external validation were 0.78, 0.78, and 0.79, respectively. Calibration curves showed a good homogeneity between the observed and predicted ongoing pregnant probabilities. Decision curve analyses revealed satisfactory clinical usefulness.

CONCLUSIONS

These novel models provide reliable and valuable prognostic predictions for patients undergoing emergency cerclage. The models can assist clinicians and patients in making personalized clinical decisions before opting for the cervical cerclage.

Factors Associated with Spontaneous Preterm Birth after Ultrasound-Indicated Cerclage

Ultrasound-indicated cerclage (UIC) is recommended to prevent spontaneous preterm birth (sPTB) in women with a short cervix at mid-trimester and a history of PTB. We assessed the factors related to sPTB after UIC and determined the corresponding risks. This retrospective cohort study was conducted at a university hospital. UIC was performed between 15 and 26 weeks of gestation in women with a cervical length of <2.5 cm. Univariate and multivariate analyses were used to examine factors associated with sPTB after UIC. An earlier gestational age and shorter cervical length at UIC were associated with sPTB after UIC. While PTB history was not associated with an increased risk of sPTB, it did increase the risk of repeat cerclage after UIC. Higher levels of preoperative serum inflammatory markers and obesity significantly increased the risk of sPTB after UIC. These findings provide helpful guidance for patient counseling and management in predicting the delivery timing after UIC in women with a short cervix in the mid-trimester.

Degree of expression of inflammatory proteins in the amniotic cavity, but not prior obstetric history, is associated with the risk severity for spontaneous preterm birth after rescue cerclage for cervical insufficiency

PROBLEM

To examine whether the severity of spontaneous preterm birth (SPTB) risk after rescue cerclage for acute cervical insufficiency (CI) is linked to the degree of inflammatory response in the amniotic fluid (AF) based on the concentrations of various inflammatory proteins and prior obstetric history.

METHOD OF STUDY

We conducted a retrospective cohort study of 65 singleton pregnant women (17-25 weeks) who underwent rescue cerclage following the diagnosis of acute CI and were subjected to amniocentesis. EN-RAGE, IL-6, IL-8, and IP-10 as inflammatory mediators and kallistatin, MMP-2/8, and uPA as extracellular matrix remodeling-related molecules were assayed in the AF using ELISA. The level of each inflammatory mediator was divided into quartiles.

RESULTS

Intra-amniotic inflammation (IAI; AF IL-6 level ≥2.6 ng/mL) was independently associated with SPTB after cerclage placement. The odds of SPTB at < 32 weeks, even after adjusting for confounders, increased significantly with each increasing quartile of baseline AF levels for each inflammatory mediator (p for trend < .05). Kaplan-Meier survival curves showed that the cerclage-to-delivery intervals were significantly shorter as the quartiles of AF EN-RAGE and MMP-8 increased (log-rank test, p < .01 each). Neither previous term birth nor prior PTB was associated with SPTB risk or cerclage-to-delivery interval after rescue cerclage. Multiparous women who experience CI after term birth showed significantly elevated levels of MMP-8 and reduced kallistatin levels in the AF.

CONCLUSION

In patients with CI, SPTB risk (especially risk severity) after rescue cerclage is associated with the degree of the inflammatory response in AF as well as the presence of IAI but not with prior obstetric history.

The efficacy of emergency cervical cerclage in singleton and twin pregnancies: a systematic review with meta-analysis

OBJECTIVE

An emergency (rescue) cervical cerclage can be offered to pregnant women presenting with dilatation and prolapsed membranes in the second trimester of pregnancy because of cervical insufficiency. This study aimed to investigate the effectiveness of an emergency cerclage in both singleton and twin pregnancies in the prevention of extreme premature birth.

DATA SOURCES

We performed a systematic literature search in PubMed and Embase from inception to June 2022 for transvaginal cervical emergency cerclages.

STUDY ELIGIBILITY CRITERIA

All studies on transvaginal cervical emergency cerclages with at least 5 patients and reporting survival were included.

METHODS

Included studies were assessed for quality and risk of bias with an adjusted Quality In Prognosis Studies tool. Random-effects meta-analyses and meta-regressions were performed for the primary outcome: survival.

RESULTS

Our search yielded 96 studies, incorporating 3239 women, including 14 studies with an expectant management control group, incorporating 746 women. Overall survival after cervical emergency cerclage was 74%, with a fetal survival of 88% and neonatal survival of 90%. Singleton and twin pregnancies showed similar survival, with a pregnancy prolongation of 52 and 37 days and a gestational age at delivery of 30 and 28 weeks, respectively. Meta-regression analyses indicated a significant inverse association between mean gestational age at diagnosis and pregnancy prolongation and no association between dilatation or gestational age at diagnosis and gestational age at delivery. Compared with expectant management, emergency cerclage significantly increased overall survival by 43%, fetal survival by 17% and neonatal survival by 22%, along with a significant pregnancy prolongation of 37 days and reduction in delivery at <28 weeks of gestation of 55%. These effects were more profound in singleton pregnancies than in twin pregnancies.

CONCLUSION

This systematic review indicates that, in pregnancies threatened by extreme premature birth because of cervical insufficiency, emergency cerclage leads to significantly higher survival, accompanied by significant pregnancy prolongation and reduction in delivery at <28 weeks of gestation, compared with expectant management. The mean gestational age at delivery was 30 weeks, independent of dilatation or gestational age at diagnosis. Survival was similar for singleton and twin pregnancies, implying that emergency cerclage should be considered in both.

The Association of Inflammatory Markers with Maternal-Neonatal Outcome After Cervical Cerclage

Objective

Cervical cerclage is effective in prolonging the number of weeks gestation in patients with cervical insufficiency(CI). However, valuable predictors with successful cervical cerclage remain limited. It aimed to evaluate the value of the systemic immune-inflammation index (SII), and systemic inflammation response index (SIRI) to predict the outcomes of cervical cerclage.

Methods

This study analyzed 374 participants. Inflammatory markers were calculated using maternal peripheral blood. The association of inflammatory markers and the outcome of cervical cerclage were analyzed. And the optimal cut-off values of inflammatory markers were calculated. Also, the Chi-square test and logistic and linear regression analyses were performed to evaluate inflammatory markers with the maternal outcome and neonatal outcomes.

Results

374 pregnancies were included in this study. Finally, 268 (71.7%) participants suffered successful cervical cerclage. This study demonstrated that the baseline BMI (cm²/kg), the bulging membrane, cervical dilation (≥2cm), the amniotic sac herniation, the neutrophils counts, the systemic immune-inflammation index (SII), and systemic inflammation response index (SIRI) were significant difference between the successful and unsuccessful groups (all P<0.05). Additionally, maternal blood inflammatory markers, such as WBC, lymphocyte, neutrophils, monocyte, platelet counts, SII, and SIRI, were significantly associated with maternal-neonatal outcomes. Furthermore, the results demonstrated that the SII level had the highest OR (OR=4.626; 95% CI (2.500-8.560)), as well as the following: SIRI level (OR = 3.795; 95% CI (1.989-7.242)), cervical dilation (≥2cm) (OR =3.477; 95% CI (1.458-10.844)), and amniotic sac herniation (OR = 1.796; 95% (0.473-4.975)).

Conclusion

This study demonstrated that the baseline SII level and SIRI level are important biochemical markers for predicting the outcome of cervical cerclage and maternal-neonatal outcomes with non-invasive procedures. They can help to provide personalized treatment before surgery and enhance postoperative surveillance.

Dynamic Change of Novel Systemic Inflammation Markers to Predict Maternal-Neonatal Prognosis After Cervical Cerclage

Objective

Cervical cerclage is an effective method to prevent preterm birth. However, the clinical indicators that can predict cervical cerclage remain limited. This study aimed to explore whether dynamically inflammatory markers are valuable biomarkers for the prognosis of cervical cerclage.

Methods

This study included 328 participants. Inflammatory markers were calculated using maternal peripheral blood before and after the cervical cerclage procedure. The Chi-square test, linear regression, and logistic regression were performed to evaluate the dynamic change of inflammatory markers with the prognosis of cervical cerclage. And the optimal cut-off values of inflammatory markers were calculated.

Results

Totally 328 pregnant women were analyzed in the study. 223 (67.99%) participants obtained successful cervical cerclage. This study revealed that the maternal age, the baseline BMI (cm²/kg), the times of gravida, the rate of recurrent abortion, the PPROM, cervical length shorter (<1.5cm), cervical dilation (≥2cm), the bulging membrane, the Pre-SII, the Pre-SIRI, the Post-SII, the Post-SIRI, and the ΔSII were significantly associated with outcomes after cervical cerclage (all P<0.05). Pre-SII, Pre-SIRI, Post-SII, Post-SIRI, and ΔSII levels were mainly related to maternal-neonatal outcomes. Furthermore, the results demonstrated that the ΔSII level had the highest OR (OR=14.560; 95% CI (4.461-47.518)). In addition, we revealed that Post-SII and ΔSII levels had the highest AUC (0.845/0.840) and relatively higher sensitivity/specificity (68.57/92.83% and 71.43/90.58%) and PPV/ NPV (81.82/86.25% and 78.13/87.07%) compared with other indicators.

Conclusion

This study suggested that the dynamic change of SII level and SIRI level are important biochemical markers to predict the prognosis of cervical cerclage and maternal-neonatal prognosis, especially the Post-SII and ΔSII levels. They can help to determine candidates for cervical cerclage before surgical procedure and enhance postoperative surveillance.

Prediction of emergency cerclage outcomes in women with cervical insufficiency: The role of inflammatory, angiogenic, and extracellular matrix-related proteins in amniotic fluid

OBJECTIVE

We aimed to determine whether various novel inflammatory, angiogenic, and extracellular matrix-related mediators in amniotic fluid (AF) can independently predict emergency cerclage outcomes in women with acute cervical insufficiency (CI).

METHODS

This was a retrospective cohort study conducted among 50 singleton pregnant women (18-25 weeks) who underwent emergency cerclage for CI and were subjected to amniocentesis. The AF samples were assayed for endoglin, endostatin, haptoglobin, insulin-like growth factor-binding protein (IGFBP)-3, -4, kallistatin, lumican, macrophage colony-stimulating factor (M-CSF), pentraxin 3, p-selectin, receptor for advanced glycation end products (RAGE), resistin, transforming growth factor beta-induced (TGFBI), and vitamin D-binding protein (VDBP) levels. Interleukin (IL)-6 levels in the AF were also measured for comparison with potential biomarkers assessed in this study. The primary endpoint was spontaneous preterm delivery (SPTD) at <34 weeks following emergency cerclage.

RESULTS

The AF levels of pentraxin 3, RAGE, and resistin were significantly higher in women who had SPTD at <34 weeks after cerclage placement (pentraxin-3: P = 0.003; RAGE: P = 0.041; and resistin; P = 0.002). In multivariate analysis, elevated AF levels of pentraxin 3 (P = 0.007) and resistin (P = 0.006), but not those of RAGE (P = 0.069), were independently associated with the occurrence of SPTD at <34 weeks after cerclage, following adjustment for baseline clinical variables (e.g., cervical dilation). The area under the curve (AUC) values of AF pentraxin 3, RAGE, and resistin for the prediction of SPTD at <34 weeks were 0.749, 0.669, and 0.770, respectively, which were similar to those of AF IL-6. However, in univariate analyses, no differences in the AF levels of endoglin, endostatin, haptoglobin, IGFBP-3, IGFBP-4, kallistatin, lumican, p-selectin, TGFBI, and VDBP were found to be associated with SPTD at <34 weeks after cerclage placement.

CONCLUSIONS

In women with acute CI, the AF levels of pentraxin 3, RAGE, and resistin could be useful novel biomarkers for predicting SPTD following emergency cerclage. However, the clinical utility of these new biomarkers should be validated in larger multicenter studies.

Antibody microarray analysis of the amniotic fluid proteome for predicting the outcome of rescue cerclage in patients with cervical insufficiency

Little is known about the biomarkers that can identify patient candidates suitable for rescue cerclage procedure. The purpose of the study was to identify novel biomarkers in amniotic fluid (AF) that can predict the outcome of rescue cerclage in patients with cervical insufficiency by using an antibody microarray. This case–control study was conducted using AF samples collected from singleton pregnant women who underwent rescue cerclage following a diagnosis of cervical insufficiency (19–25 weeks). Patients were divided into case (n=20) and control (n=20) groups based on the occurrence of spontaneous preterm delivery (SPTD) at <34 weeks of gestation after cerclage placement. The AF proteomes were analyzed using an antibody microarray for biomarker discovery work. Ten candidate biomarkers of interest were validated by enzyme-linked immunosorbent assay (ELISA). Thirty-one molecules studied showed significant intergroup differences (≥two-fold change in signal intensity). Validation by ELISA confirmed significantly higher levels of a proliferation-inducing ligand (APRIL), S100 calcium-binding protein A8/A9 complex (S100 A8/A9), tissue inhibitors of metalloproteinase-1 (TIMP-1), macrophage inflammatory protein-1α (MIP-1α), and interleukin-8 (IL-8) in women who had SPTD at <34 weeks. Of these, AF S100 A8/A9 and TIMP-1 levels were independent of other potentially confounding factors (e.g., cervical dilatation). S100 A8/A9 had the highest area under the curve (AUC) at 0.857. Using protein–antibody microarray technology, we identified differentially expressed proteins (DEPs) and several novel biomarkers (APRIL, IL-8, MIP-1α, S100 A8/A9, and TIMP-1) in AF from women who had SPTB at <34 weeks after cerclage for cervical insufficiency. These data can provide an insight into the molecular mechanisms underlying SPTD after rescue cerclage in patients with cervical insufficiency.

Proteomic identification of biomarkers in maternal plasma that predict the outcome of rescue cerclage for cervical insufficiency

Objective

We sought to identify plasma protein biomarkers that are predictive of the outcome of rescue cerclage in patients with cervical insufficiency.

Methods

This retrospective cohort study included 39 singleton pregnant women undergoing rescue cerclage for cervical insufficiency (17–25 weeks) who gave plasma samples. Three sets of pooled plasma samples from controls (cerclage success, n = 10) and cases (cerclage failure, n = 10, defined as spontaneous preterm delivery at <33 weeks) were labeled with 6-plex tandem mass tag (TMT) reagents and analyzed by liquid chromatography-tandem mass spectrometry. Differentially expressed proteins between the two groups were selected from the TMT-based quantitative analysis. Multiple reaction monitoring-mass spectrometry (MRM-MS) analysis was further used to verify the candidate proteins of interest in patients with cervical insufficiency in the final cohort (n = 39).

Results

From MRM-MS analysis of the 40 proteins showing statistically significant changes (P < 0.05) from the TMT-based quantitative analysis, plasma IGFBP-2, PSG4, and PGLYRP2 levels were found to be significantly increased, whereas plasma MET and LXN levels were significantly decreased in women with cerclage failure. Of these, IGFBP-2, PSG4, and LXN levels in plasma were independent of cervical dilatation. A multiple-biomarker panel was developed for the prediction of cerclage failure, using a stepwise regression procedure, which included the plasma IGFBP-2, PSG4, and LXN (area under the curve [AUC] = 0.916). The AUC for this multiple-biomarker panel was significantly greater than the AUC for any single biomarker included in the multi-biomarker model.

Conclusions

Proteomic analysis identified useful and independent plasma biomarkers (IGFBP-2, PSG4, and LXN; verified by MRM) that predict poor pregnancy outcome following rescue cerclage. Their combined analysis in a multi-biomarker panel significantly improved predictability.

Proteomic Analysis of Amniotic Fluid Proteins for Predicting the Outcome of Emergency Cerclage in Women with Cervical Insufficiency

We aimed to identify novel biomarkers in amniotic fluid (AF) that predict the outcome of emergency cerclage in women with cervical insufficiency. This retrospective cohort study included 40 singleton pregnant women who received emergency cerclage for cervical insufficiency (17-25 weeks) and underwent amniocentesis. Label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to identify AF proteins in pooled samples (n = 16) using a nested case-control approach. The six candidate biomarkers of interest were validated by enzyme-linked immunosorbent assays (ELISA) in the final cohort (n = 40). The differentially expressed proteins (DEPs) were analyzed by pathway analysis software. The primary outcome measure was failure of emergency cerclage [defined as spontaneous preterm delivery (SPTD) at < 34 weeks of gestation after cerclage placement]. Sixty-eight proteins were differentially expressed (P < 0.001) in AF from SPTD cases and near-term controls, of which 44 (64.7%) were upregulated and 24 (35.3%) were downregulated. Validation by ELISA confirmed that AF from women with cerclage failure contained significantly higher levels of myeloperoxidase, lactoferrin, glucose-6-phosphate isomerase, lipocalin-2, and lymphocyte cytosolic protein 1, the first four of which were independent of cervical dilatation at presentation. The five pathways with the most differentially regulated proteins were actin cytoskeleton signaling, acute phase response signaling, ILK signaling, glycolysis, and gluconeogenesis. Proteomic analyses of AF in this study identified DEPs and specific protein pathways related to poor prognosis after emergency cerclage for cervical insufficiency. Four novel independent biomarkers in AF for cerclage failure have been identified using proteomics.

The Identification of Immune-Related Plasma Proteins Associated with Spontaneous Preterm Delivery and Intra-Amniotic Infection in Women with Premature Cervical Dilation or an Asymptomatic Short Cervix

BACKGROUND

We aimed to investigate whether various immune-related plasma proteins, alone or in combination with conventional clinical risk factors, can predict spontaneous preterm delivery (SPTD) and intra-amniotic infection in women with premature cervical dilation or a short cervix (≤ 25 mm).

METHODS

This retrospective study included 80 asymptomatic women with premature cervical dilation (n = 50) or a short cervix (n = 30), who underwent amniocentesis at 17-29 weeks. Amniotic fluid (AF) was cultured, and maternal plasma was assayed for interleukin (IL)-6, matrix metalloproteinase (MMP)-9, tissue inhibitor of metalloproteinases (TIMP)-1, and complements C3a and C5a, using enzyme-linked immunosorbent assay (ELISA) kits. The primary outcome measures were SPTD at < 32 weeks and positive AF cultures.

RESULTS

The plasma levels of IL-6, C3a, and C5a, but not of MMP-9 and TIMP-1, were significantly higher in women with SPTD at < 32 weeks than in those who delivered at ≥ 32 weeks. The women who delivered at < 32 weeks had more advanced cervical dilatation, and higher rates of antibiotic and tocolytic administration and were less likely to be given vaginal progesterone than those who delivered at ≥ 32 weeks. Using a stepwise regression analysis, a combined prediction model was developed, which included the plasma IL-6 and C3a levels, and cervical dilatation (area under the curve [AUC], 0.901). The AUC for this model was significantly greater than that for any single variable included in the predictive model. In the univariate analysis, plasma IL-6 level was the only significant predictor of intra-amniotic infection.

CONCLUSION

In women with premature cervical dilation or a short cervix, maternal plasma IL-6, C3a, and C5a levels could be useful non-invasive predictors of SPTD at < 32 weeks. A combination of these biomarkers and conventional clinical factors may clearly improve the predictability for SPTD, as compared with the biomarkers alone. An increased plasma level of IL-6 predicted intra-amniotic infection.

Inflammation induced preterm labor and birth

Preterm birth which occurs before 37 weeks gestation is one of the most common obstetrical complication in humans. After many studies, it appears that "not one answer fits all" regarding the risk factors, causes and the treatments for this syndrome. However, it is becoming more evident that one of the major risk factors is inflammation and/or infection in the fetoplacental unit. In animal models (usually consisting of mice injected with lipopolysaccharide at 14 days of gestation), IL-22 and IL-6 have been identified as factors related to preterm birth. There are some clinical tests available to determine the risk for preterm labor and delivery, which can be identified before, during early, or at mid-gestation. However, treatment of preterm birth with antibiotics so far has not been "curable" and studies using anti-inflammatory treatments are not readily available. More studies regarding causes and treatments for preterm labor and delivery in humans are necessary to prevent neonatal deaths and/or developmental abnormalities associated with this common syndrome.

Amniotic fluid proteomic signatures of cervical insufficiency and their association with length of latency

PROBLEM

Cervical insufficiency is a precursor of preterm birth. Treatment with emergency cervical cerclage is contraindicated in the presence of intra-amniotic infection. Detecting infection with Gram stain and culture of amniotic fluid lacks sensitivity. Proteomic profiling of amniotic fluid in cervical insufficiency may help identify pregnancies best suited for emergency cerclage.

METHOD OF STUDY

Thirty-two pregnant women underwent amniocentesis for routine genetic testing (n = 22) or after diagnosis of cervical insufficiency (n = 10). The proteomic profiles of the amniotic fluid samples were compared in a cross-sectional fashion, including sub-analyses of women with cervical insufficiency and latency periods of <1 week and >1 week post-diagnosis.

RESULTS

Mean gestational age at diagnosis of cervical insufficiency was 21.4 weeks (95% CI 20.6-22.1). Proteomic analysis yielded 40 (7.2%, P < 0.05) differentially expressed proteins between women with delivery <1 week (n = 6) vs. >1 week (n = 4). Women who delivered <1 week had activated inflammatory response (z = 2.3, P = 6.71E-09), chemotaxis of immune cells (z = 2.9, P = 2.01E-08), and inhibited bacterial growth (z = -2.2, P = 5.82E-05). A multivariate model of eight biomarkers positively associated with cases of <1 week latency and distinguished cases from controls (97.8%, cross-validation accuracy 92.7%, P = 0.0009).

CONCLUSION

In this pilot study, significant differences in the amniotic fluid proteomic profiles in cases of cervical insufficiency compared to genetic amniocentesis were observed. Proteomic signatures were predictive of achieving latency > 1 week after diagnosis of cervical insufficiency. These preliminary findings suggest that proteomic analysis may be of value in predicting outcome following cervical insufficiency and warrants further validation in larger studies.

Cervical cerclage placement decreases local levels of proinflammatory cytokines in patients with cervical insufficiency

BACKGROUND

Cervical insufficiency is characterized by premature, progressive dilation and shortening of the cervix during pregnancy. If left unattended, this can lead to the prolapse and rupture of the amniotic membrane, which usually results in midtrimester pregnancy loss or preterm birth. Previous studies have shown that proinflammatory cytokines such as interleukin-1β, interleukin-6, interleukin-8, and tumor necrosis factor alpha are up-regulated in normal parturition but are also associated with preterm birth. Studies evaluating such markers in patients with cervical insufficiency have evaluated only their diagnostic potential. Even fewer studies have studied them within the context of cerclage surgery.

OBJECTIVES(S)

The objective of the study was to evaluate the impact of local and systemic inflammatory markers on the pathogenesis of cervical insufficiency and the effect of cerclage surgery on the local immune microenvironment of women with cervical insufficiency.

STUDY DESIGN

We recruited 28 pregnant women (12-20 weeks' gestation) diagnosed with insufficiency and referred for cerclage surgery and 19 gestational age-matched normal pregnant women as controls. Serum and cervicovaginal fluid samples were collected before and after cerclage surgery and during a routine checkup for normal women and analyzed using a targeted 13-plex proinflammatory cytokine assay.

RESULTS

Before surgery, patients with cervical insufficiency had higher levels of interleukin-1β, interleukin-6, interleukin-12, monocyte chemoattractant protein-1 and tumor necrosis factor alpha in cervicovaginal fluid compared to controls, but after surgery, these differences disappeared. No differences were found in serum of insufficiency versus control women. In patients with insufficiency, the levels of interleukin-1β, interleukin-6, interleukin-8, monocyte chemoattractant protein-1, and interferon gamma in cervicovaginal fluid declined significantly after cerclage compared with before intervention, but these changes were not detected in serum.

CONCLUSION

Compared with normal women, patients with cervical insufficiency have elevated levels of proinflammatory cytokines in cervicovaginal fluid but not in serum, suggesting a dysregulation of the local immune environment. Cerclage intervention led to a significant decline in these proinflammatory cytokines, suggesting that cerclage may help reduce local inflammation in cervical insufficiency.

Good prognosis of cerclage in cases of cervical insufficiency when intra-amniotic inflammation/infection is ruled out

OBJECTIVE

To determine if absence of sub-clinical intra-amniotic inflammation improves the prognosis of rescue cerclage in cases of bulging membranes.

METHODS

Cohort study with all women with bulging membranes admitted into our hospital between 2009 and 2013. Patients underwent amniocentesis to quantify amniotic glucose, leukocytes, IL-6 and leukocyte esterase levels and for microbiological culture. All patients without intra-amniotic inflammation or sub-clinical chorioamnionitis were proposed a physical examination-indicated cervical cerclage. Those who did not accept were treated with bed rest.

RESULTS

We enrolled 31 women. Median gestational age at diagnosis was 23 + 1 (21–25 + 4) weeks. Median interval until delivery was 12 (3–52.5) d. IL-6 had the highest diagnostic accuracy for good prognosis. Patients with IL6 <2.90 ng/ml were diagnosed later in pregnancy and presented a longer interval until delivery (89 versus 4 d), higher gestational age at delivery (35 + 1 versus 23 + 3 weeks) and a lower rate of prematurity (54.5% versus 100%) and perinatal mortality (0% versus 80%) than those with IL-6 ≥2.90 ng/ml. Rescue cerclage and low Il-6 were the best predictors of good outcome.

CONCLUSION

IL-6 levels in amniotic fluid may be of clinical value for individualizing the management of patients with bulging membranes for placement of rescue cerclage.

Evidence of perturbations of the cytokine network in preterm labor

OBJECTIVE

Intraamniotic inflammation/infection is the only mechanism of disease with persuasive evidence of causality for spontaneous preterm labor/delivery. Previous studies about the behavior of cytokines in preterm labor have been largely based on the analysis of the behavior of each protein independently. Emerging evidence indicates that the study of biologic networks can provide insight into the pathobiology of disease and improve biomarker discovery. The goal of this study was to characterize the inflammatory-related protein network in the amniotic fluid of patients with preterm labor.

STUDY DESIGN

A retrospective cohort study was conducted that included women with singleton pregnancies who had spontaneous preterm labor and intact membranes (n = 135). These patients were classified according to the results of amniotic fluid culture, broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry, and amniotic fluid concentration of interleukin (IL)-6 into the following groups: (1) those without intraamniotic inflammation (n = 85), (2) those with microbial-associated intraamniotic inflammation (n = 15), and (3) those with intraamniotic inflammation without detectable bacteria (n = 35). Amniotic fluid concentrations of 33 inflammatory-related proteins were determined with the use of a multiplex bead array assay.

RESULTS

Patients with preterm labor and intact membranes who had microbial-associated intraamniotic inflammation had a higher amniotic fluid inflammatory-related protein concentration correlation than those without intraamniotic inflammation (113 perturbed correlations). IL-1β, IL-6, macrophage inflammatory protein (MIP)-1α, and IL-1α were the most connected nodes (highest degree) in this differential correlation network (degrees of 20, 16, 12, and 12, respectively). Patients with sterile intraamniotic inflammation had correlation patterns of inflammatory-related proteins, both increased and decreased, when compared to those without intraamniotic inflammation (50 perturbed correlations). IL-1α, MIP-1α, and IL-1β were the most connected nodes in this differential correlation network (degrees of 12, 10, and 7, respectively). There were more coordinated inflammatory-related protein concentrations in the amniotic fluid of women with microbial-associated intraamniotic inflammation than in those with sterile intraamniotic inflammation (60 perturbed correlations), with IL-4 and IL-33 having the largest number of perturbed correlations (degrees of 15 and 13, respectively).

CONCLUSIONS

We report for the first time an analysis of the inflammatory-related protein network in spontaneous preterm labor. Patients with preterm labor and microbial-associated intraamniotic inflammation had more coordinated amniotic fluid inflammatory-related proteins than either those with sterile intraamniotic inflammation or those without intraamniotic inflammation. The correlations were also stronger in patients with sterile intraamniotic inflammation than in those without intraamniotic inflammation. The findings herein could be of value in the development of biomarkers of preterm labor.

Predicting outcomes of emergency cerclage in women with cervical insufficiency using inflammatory markers in maternal blood and amniotic fluid

OBJECTIVE

To identify inflammatory markers in maternal blood and amniotic fluid that can predict outcomes of emergency cerclage in women with cervical insufficiency.

METHODS

This retrospective cohort study included patients at 18-24 weeks of pregnancy who underwent amniocentesis before receiving emergency cerclage for cervical insufficiency between August 2004 and August 2013 at a university teaching hospital in South Korea. Total and differential white blood cell counts were measured during amniocentesis. Amniotic fluid was cultured and analyzed for the presence of interleukin (IL)-6 and IL-8. The primary outcome measure was spontaneous preterm delivery (SPTD) at less than 32weeks of pregnancy following cerclage placement.

RESULTS

Of 37 patients, 18 (49%) experienced SPTD at less than 32weeks of pregnancy. These patients were found to have significantly more advanced cervical dilatation at presentation, as well as higher mean neutrophil-lymphocyte ratios (NLRs) and higher IL-6 and IL-8 levels in amniotic fluid in comparison with those who did not experience SPTD at less than 32weeks of pregnancy. In a multivariable analysis, a high NLR and high amniotic fluid IL-8 levels showed a significant correlation with the occurrence of SPTD at less than 32weeks of pregnancy (P=0.032).

CONCLUSION

Pre-operative NLR and amniotic fluid IL-8 levels may be important markers for predicting emergency cerclage outcomes in women with cervical insufficiency.

Adjunctive Pessary Therapy after Emergency Cervical Cerclage for Cervical Insufficiency with Protruding Fetal Membranes in the Second Trimester of Pregnancy: A Novel Modification of Treatment

AIM

To evaluate the effectiveness of adjunctive pessary therapy after emergency cervical cerclage (ECC) in improving perinatal outcome in cervical insufficiency with fetal membranes protruding into the vagina.

MATERIAL AND METHODS

A retrospective analysis of patients treated at the 1st Department of Obstetrics and Gynecology, Medical University of Warsaw, between 2008 and 2013. The study group consisted of 15 women treated with ECC and a pessary and the control group consisted of 17 patients treated with cerclage only.

RESULTS

The mean gestational age at delivery was significantly higher in the study group (34.7 versus 29.7 weeks, p = 0.03). The period between cerclage insertion and delivery was significantly longer in the study group (82.9 versus 52.1 days, p = 0.045). The mean neonatal birthweight and neonatal "discharge alive" ratio were higher in the study group, although not statistically significant (2550 g versus 1883 g, p = 0.14, and 93.3% versus 70.5%, p = 0.18, resp.). NICU hospitalization rates were comparable (33.3% versus 35.3%, p = 0.9).

CONCLUSIONS

Adjunctive pessary therapy allows delaying delivery in women treated with ECC due to cervical insufficiency with protruding fetal membranes. It also seems to improve neonatal outcome, although the differences are not statistically significant. Further prospective study is required to prove these findings.

Emergency Cerclage: Improvement of Outcomes by Standardization of Management

INTRODUCTION

Cervical dilatation followed by prolapse and ballooning of membranes into the vagina at mid-gestation is a critical situation. The aim of this study was to describe the outcome of emergency cerclage in a tertiary referral center during a 10-year period (2001-2010) in which a defined selection of women and standard protocol were introduced.

SUBJECTS AND METHODS

Thirty-nine cases of emergency cervical cerclage performed before 24 completed weeks were retrospectively reviewed. Data related to maternal history, diagnosis, procedure details, postoperative management and perinatal outcome were recorded. Maternal characteristics and perinatal outcomes are described.

RESULTS

Gestational age at cerclage (mean ± SD) was 22.1 ± 2.0 weeks with 61% (24/39) of women presenting bulging membranes. Gestational age at delivery and cerclage-to-delivery time (mean ± SD) were 28.6 ± 6.2 weeks and 49.1 ± 36.5 days, respectively. Only 38.5% (15/39) of the whole group and 44.1% (15/34) of those who reached 24.0 weeks delivered beyond 28 weeks of gestational age. Neonatal survival before discharge was 82.4% (28/34).

DISCUSSION

Perinatal outcomes after emergency cerclage are still poor with more than half of the cases delivering before 28 weeks. A standard protocol may help in the management of these rare cases.

[Cervical cerclage]

Cervical cerclage aims to strengthen not only the mechanical properties of the cervix, but also its immunological and anti-infectious functions. The demonstration of a strong interrelation between cervical insufficiency as well as decreased cervical length at endo-vaginal ultrasonography and infection has changed the indications cerclage. Actually we can distinguish three indications for cerclage: prophylactic, for obstetrical history; therapeutic, for shortened cervical length at ultrasonography in patients at risk and; emergency cerclage in case of threatening cervix at physical examination. The McDonald's technique is the most recommended. In case of failure, it is proposed to realize cerclage at a higher level on the cervix either by vaginal or abdominal route.

Polymorphisms in Genes Coding for Cytokines, Mannose-Binding Lectin, Collagen Metabolism and Thrombophilia in Women with Cervical Insufficiency

OBJECTIVE

To study the association between cervical insufficiency and single nucleotide polymorphisms in seven genes coding for pro- and anti-inflammatory cytokine-related factors, mannose-binding lectin 2 (MBL2), collagen1α1 (COL1A1), factor II and factor V Leiden genes.

METHODS

In a case-control study, potential maternal biomarkers for cervical insufficiency were investigated in 30 women with a history of second-trimester miscarriage or preterm birth due to cervical insufficiency and in 70 control women.

RESULTS

Homozygous carriers of the interleukin 6 (IL6) -174 genotype GG had an odds ratio (OR) of 3.1 [95% confidence interval (95% CI) 1.3-7.4, p = 0.01] and MBL2 genotypes coding for low or intermediate levels of plasma MBL had an OR of 3.3 (95% CI 1.2-9.0, p = 0.01) for cervical insufficiency compared with controls. Serum MBL levels were lower in women with cervical insufficiency than in controls (median 408 and 1,985 ng/ml, respectively, p < 0.01).

CONCLUSIONS

Single nucleotide polymorphisms in the IL6 gene and the MBL2 gene and low MBL levels related to the latter polymorphism may increase the risk of preterm birth due to cervical insufficiency.

The relationship between the intensity of intra-amniotic inflammation and the presence and severity of acute histologic chorioamnionitis in preterm gestation

OBJECTIVE

Acute histologic chorioamnionitis (HCA) is associated with an increased risk of perinatal mortality and morbidity. The purpose of this study was to determine the relationship between the intensity of intra-amniotic inflammation (IAI) and the severity of acute HCA in preterm gestation.

METHODS

The relationship between the intensity of IAI and the presence and severity of acute HCA was examined in 412 patients with singleton gestations who delivered within 120 h of transabdominal amniocentesis. The concentration of amniotic fluid (AF) matrix metalloproteinase (MMP)-8 was assayed to determine the presence and intensity of IAI. Acute HCA was defined as the presence of inflammatory change in any tissue samples according to the criteria previously reported. The total grade of acute HCA was used to determine the severity of HCA.

RESULTS

(1) Patients with IAI had a significantly higher rate of acute HCA than those without IAI [76.9% (133/173)] versus 20.9% (50/239), p < 0.001]. The AF MMP-8 concentration was significantly higher in patients with acute HCA than in those without acute HCA (median [range]; 188.3 ng/ml [0.3-6142.6] versus 1.8 ng/ml [0.3-2845.5], p < 0.001); (2) Of 183 patients with acute HCA, the AF MMP-8 concentration was positively correlated with the severity of acute HCA (p < 0.001).

CONCLUSIONS

AF MMP-8 concentration was not only a predictor of the presence of acute HCA, but its concentration also correlated with the severity of acute HCA. The higher the intensity of IAI, the worse the degree of acute HCA in preterm gestation.

Elevation of soluble form of receptor for advanced glycation end products (sRAGE) in recurrent pregnancy losses (RPL): possible participation of RAGE in RPL

OBJECTIVE

To determine whether the soluble receptor for advanced glycation end products (sRAGE) and immune inflammatory markers are associated with recurrent pregnancy losses (RPL).

DESIGN

Prospective case-control study.

SETTING

University clinic.

PATIENT(S)

A total of 93 women (age 35.8±4.6 years) were enrolled including 63 women with three or more recurrent pregnancy losses (RPL), and age-matched fertile controls with a history of at least one live birth and no history of pregnancy losses (n=30).

INTERVENTION(S)

Peripheral blood collection.

MAIN OUTCOME MEASURE(S)

Assessment of anthropometric, metabolic, and inflammatory immune variables.

RESULT(S)

Levels of sRAGE were statistically significantly higher in RPL patients than in control patients (1,528.9±704.5 vs. 1,149.9±447.4 pg/mL). In the multivariate analysis, the levels of insulin, plasminogen activator inhibitor-1, the resistance index of the uterine radial artery, and the ratio of tumor necrosis factor-α/interleukin-10 producing T helper cells were statistically significantly associated with the serum sRAGE level.

CONCLUSION(S)

Elevated levels of serum sRAGE are associated with RPL. The soluble receptor for advanced glycation end products might contribute to RPL by reducing uterine blood flow and subsequently causing ischemia in the fetus via inflammatory and thrombotic reactions.

Emergency cerclage: literature review

This article reviews the use and effectiveness of emergency cerclage for women who present with a dilated cervix in the second trimester of pregnancy and seeks to identify predictors of favorable emergency cerclage outcomes. We searched PubMed and the Cochrane Library for the period January 1995 to April 2012 and used the terms "emergency cerclage," "emergency stitch," "rescue cerclage," and "rescue stitch." Thirty-four studies in which transvaginal emergency cervical cerclage was performed in women with a dilated cervix were identified and included. Predictors of poor outcome were prolapsed membranes, evidence of intra-amniotic or systemic infection, symptomatic presentation, cervical dilatation greater than 3 cm, or cerclage after 22 weeks. According to observational and limited randomized controlled trials, the cerclage group did significantly better than the bed-rest group in mean randomization-to-delivery interval, preterm delivery before 34 weeks, and compound neonatal morbidity. The current data suggest that emergency cerclage is associated with a longer latency period and, most often, with better pregnancy outcomes when compared with bed rest. Many of the predictors of adverse outcomes appear to be associated with evidence of inflammation or infection.

TARGET AUDIENCE

Obstetricians and gynecologists, family physicians

LEARNING OBJECTIVES

After completing this CME activity, physicians should be better able to review the use and evaluate the effectiveness of emergency cerclage for women who present with a dilated cervix in the second trimester, to identify predictors of favorable emergency cerclage outcomes, and to compare emergency cerclage versus bed rest.