Prediction of impending preterm delivery based on sonographic cervical length and different cytokine levels in cervicovaginal fluid in preterm labor

Changes in cytokine and sequestosome-1 levels during twin pregnancy progression: Association with outcome

BACKGROUND

Twin pregnancies are associated with complications and adverse outcomes. The number of twin pregnancies has increased in the last decades, due to the use of assisted reproductive techniques and delayed childbearing. Analysis of changes that occur during twin pregnancy progression and their association with outcome will lead to improved clinical interventions.

OBJECTIVE

We evaluated if the plasma concentration of select cytokines and the level of sequestosome-1 (p62) in peripheral blood mononuclear cells (PBMCs) during each trimester of twin gestations was predictive of pregnancy outcome.

STUDY DESIGN

This prospective, observational study was conducted at Careggi University Hospital, Florence, Italy. Plasma from 82 women with twin pregnancies was collected in each trimester for measurement of interleukin (IL)-1β, IL-6, IL-10, IL-12 and tumor necrosis factor (TNF)-α. The intracellular PBMC concentration of p62, a protein involved in autophagy, kinase activity and cell differentiation, was also determined.

RESULTS

IL-1β (p < 0.001), IL-6 (p < 0.001), TNF-α (p < 0.001) and p62 (p < 0.05) increased from the 1st to the 2nd to the 3rd trimester. The TNF-α level was correlated with the IL-1β concentration in the 1st and 3rd trimesters p < 0.01) and with the IL-6 concentration in each of the three trimesters (p < 0.01). The intracellular p62 level in PBMCs was negatively correlated with the concentration of IL-1β in the 2nd trimester (p < 0.05) and negatively correlated with the IL-6 level in the 3rd trimester (p < 0.05). The TNF-α level was significantly higher in the 2nd (p < 0.05) and 3rd (p < 0.001) trimester in women with a spontaneous preterm delivery. The TNF-α concentrations in the 2nd (p < 0.05) and 3rd (p < 0.01) trimester, respectively, and 3rd trimester IL-6 (p < 0.01), were negatively associated with gestational age at delivery. The concentration of IL-6 was highest in the 2nd (p < 0.05) and 3rd (p < 0.05) trimesters in women who utilized assisted reproductive technologies. An elevated IL-1β level in the 3rd trimester was associated with gestational diabetes mellitus (p < 0.05).

CONCLUSION

Variations in cytokine levels between individual women during the three trimesters of twin gestations are predictive of spontaneous preterm delivery and the onset of gestational diabetes.

Early prediction of spontaneous preterm birth before 34 gestational weeks based on a combination of inflammation-associated plasma proteins

Background

In order to identify and possibly offer prophylactic treatment to women at risk for preterm birth (PTB), novel prediction models for PTB are needed. Our objective was to utilize high-sensitive plasma protein profiling to investigate whether early prediction of spontaneous PTB (sPTB) before 34 gestational weeks (gw) was possible in a low-risk population.

Methods

A case-control study was conducted on 46 women with sPTB before 34 gw and 46 women with normal pregnancies and term deliveries. Prospectively collected plasma sampled at gw 11 (range 7-16) and gw 25 (range 23-30) was analyzed with a high-sensitivity Proximity Extension Assay for levels of 177 inflammation-associated proteins, and statistically processed with multivariate logistic regression analysis.

Results

In the first trimester, higher levels of hepatocyte growth factor (HGF) were associated with sPTB <34 gw (OR 1.49 (1.03-2.15)). In the second trimester, higher levels of interleukin (IL)-10 (OR 2.15 (1.18-3.92)), IL-6 (OR 2.59 (1.34-4.99)), and the receptor activator of nuclear factor κB (RANK) (OR 2.18 (1.26-3.77)) were associated with sPTB <34 gw. The area under the curve for the prediction models including these proteins was 0.653 (0.534-0.759) in the first trimester and 0.854 (0.754-0.925) in the second trimester.

Conclusion

A combination of inflammation-associated plasma proteins from the second trimester of pregnancy showed a good predictive ability regarding sPTB before 34 gw, suggesting it could be a valuable supplement for the assessment of the clinical risk of sPTB. However, although a high number (n=177) of plasma proteins were analyzed with a high-sensitivity method, the prediction of sPTB in the first trimester remains elusive.

The vaginal immunoproteome for the prediction of spontaneous preterm birth: A retrospective longitudinal study

Background

Preterm birth is the leading cause of neonatal morbidity and mortality worldwide. Most cases of preterm birth occur spontaneously and result from preterm labor with intact (spontaneous preterm labor [sPTL]) or ruptured (preterm prelabor rupture of membranes [PPROM]) membranes. The prediction of spontaneous preterm birth (sPTB) remains underpowered due to its syndromic nature and the dearth of independent analyses of the vaginal host immune response. Thus, we conducted the largest longitudinal investigation targeting vaginal immune mediators, referred to herein as the immunoproteome, in a population at high risk for sPTB.

Methods

Vaginal swabs were collected across gestation from pregnant women who ultimately underwent term birth, sPTL, or PPROM. Cytokines, chemokines, growth factors, and antimicrobial peptides in the samples were quantified via specific and sensitive immunoassays. Predictive models were constructed from immune mediator concentrations.

Results

Throughout uncomplicated gestation, the vaginal immunoproteome harbors a cytokine network with a homeostatic profile. Yet, the vaginal immunoproteome is skewed toward a pro-inflammatory state in pregnant women who ultimately experience sPTL and PPROM. Such an inflammatory profile includes increased monocyte chemoattractants, cytokines indicative of macrophage and T-cell activation, and reduced antimicrobial proteins/peptides. The vaginal immunoproteome has improved predictive value over maternal characteristics alone for identifying women at risk for early (<34 weeks) sPTB.

Conclusions

The vaginal immunoproteome undergoes homeostatic changes throughout gestation and deviations from this shift are associated with sPTB. Furthermore, the vaginal immunoproteome can be leveraged as a potential biomarker for early sPTB, a subset of sPTB associated with extremely adverse neonatal outcomes.

Funding

This research was conducted by the Perinatology Research Branch, Division of Obstetrics and Maternal-Fetal Medicine, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, U.S. Department of Health and Human Services (NICHD/NIH/DHHS) under contract HHSN275201300006C. ALT, KRT, and NGL were supported by the Wayne State University Perinatal Initiative in Maternal, Perinatal and Child Health.

Placental Cannabinoid Receptor Expression in Preterm Birth

Background: The cannabinoid receptor (CBR) plays a significant role in oogenesis, pregnancy, and childbirth. It might also play a significant role in preterm birth (PTB). The aim of the study was to investigate the association between the expression of the CBR in the placenta and the incidence of PTB. Methods: This prospective, observational, multicentre preliminary study was conducted on placental samples obtained from 109 women. The study included 95 patients hospitalized due to the high risk of PTB. They were divided into two groups: Group 1, where the expression of the CBR1 and CBR1a was analyzed, and Group 2, in which we examined CBR2 expression. The control group, that is, Group 3, consisted of 14 women who delivered at term, and their placentas were tested for the presence of all three receptor types (CBR1, CBR1a, and CBR2). Results: The study used reverse transcription and real-time PCR methods to assess the expression of CBRs in the placental tissues. The expression of the CBR2, CBR1, and CBR1a receptors was significantly lower in the placentas of women after PTB compared to those after term births, p = 0.038, 0.033, and 0.034, respectively. Conclusions: The presence of CBR mRNA in the human placental tissue was confirmed. The decreased expression of CBRs could serve as an indicator in predicting PTB.

Predicting preterm birth within 2 weeks in asymptomatic women with a short cervix: Combined effects of cervicovaginal fluid cytokine levels and fetal fibronectin test

AIMS

To predict preterm birth (PTB) accurately, we conducted a comprehensive cytokine assay using cervicovaginal fluid (CVF) and evaluated the additive effects of cytokine levels on the fetal fibronectin (fFN) test.

METHODS

A total of 645 CVF samples were collected from 256 asymptomatic pregnant women between 24 and 35 weeks gestation, exhibiting short cervix. After selection based on specific criteria, 17 cytokines in 105 CVF samples were simultaneously measured using multiplex assay. Multivariate logistic regression analysis was performed to evaluate the association between cytokine levels and impending PTB, which is defined as PTB within 2 weeks after CVF collection. Moreover, receiver operating characteristic (ROC) analysis was performed in women with positive fFN results, which was validated using another set of 65 CVF samples.

RESULTS

In positive fFN women, the CCL2 level was significantly higher in the impending PTB group than the other group (p < 0.01) and a predictor of impending PTB (adjusted odds ratio 1.020, 95% confidence interval [95% CI] 1.003-1.038, p = 0.020). The cutoff value of CCL2 was 64.8 pg/mL (are under the curve 0.726, p = 0.004, 95% CI 0.593-0.859, sensitivity 45.2%, specificity 91.7%). Additionally, the reliable classification performance of proposed ROC model could be validated. However, measuring cytokine levels could not help in predicting impending PTB in women with negative fFN or normal labor onset in healthy-term women.

CONCLUSION

Comprehensive analysis of CVF cytokines revealed that the CCL2 level significantly improves the prediction of impending PTB in asymptomatic fFN-positive women with a short cervix, which may contribute to better clinical management.

A Novel Predictive Machine Learning Model Integrating Cytokines in Cervical-Vaginal Mucus Increases the Prediction Rate for Preterm Birth

Preterm birth (PB) is a leading cause of perinatal morbidity and mortality. PB prediction is performed by measuring cervical length, with a detection rate of around 70%. Although it is known that a cytokine-mediated inflammatory process is involved in the pathophysiology of PB, none screening method implemented in clinical practice includes cytokine levels as a predictor variable. Here, we quantified cytokines in cervical-vaginal mucus of pregnant women (18-23.6 weeks of gestation) with high or low risk for PB determined by cervical length, also collecting relevant obstetric information. IL-2, IL-6, IFN-γ, IL-4, and IL-10 were significantly higher in the high-risk group, while IL-1ra was lower. Two different models for PB prediction were created using the Random Forest machine-learning algorithm: a full model with 12 clinical variables and cytokine values and the adjusted model, including the most relevant variables-maternal age, IL-2, and cervical length- (detection rate 66 vs. 87%, false positive rate 12 vs. 3.33%, false negative rate 28 vs. 6.66%, and area under the curve 0.722 vs. 0.875, respectively). The adjusted model that incorporate cytokines showed a detection rate eight points higher than the gold standard calculator, which may allow us to identify the risk PB risk more accurately and implement strategies for preventive interventions.

Exploring Plasma-Level Gut Microbiota Mediators and Pro-Inflammatory Markers in Pregnant Women with Short Cervix and Gestational Diabetes Mellitus

The composition of the gut microbiota (GM) undergoes significant changes during pregnancy, influenced by metabolic status, energy homeostasis, fat storage, and hormonal and immunological modifications. Moreover, dysbiosis during pregnancy has been associated with preterm birth, which is influenced by factors such as cervical shortening, infection, inflammation, and oxidative stress. However, dysbiosis also affects the levels of lipopolysaccharide-binding protein (LBP), short-chain fatty acids (SCFAs), and free fatty acids (FFA) in other tissues and the bloodstream. In this study, we investigated the plasmatic levels of some pro-inflammatory cytokines, such as matrix metalloproteinases-8 (MMP-8), interleukin-8 (IL-8), heat shock protein 70 (Hsp70), and microbial markers in pregnant women with a short cervix (≤25 mm) compared to those with normal cervical length (>25 mm). We examined the differences in the concentration of these markers between the two groups, also assessing the impact of gestational diabetes mellitus. Understanding the relationship between GM dysbiosis, inflammatory mediators, and cervical changes during pregnancy may contribute to the identification of potential biomarkers and therapeutic targets for the prevention and management of adverse pregnancy outcomes, including preterm birth.

Inflammatory biomarkers in the cervicovaginal fluid to identify histologic chorioamnionitis and funisitis in women with preterm labor

OBJECTIVE

We investigated the association between altered levels of inflammatory proteins in the cervicovaginal fluid (CVF) and acute histologic chorioamnionitis (HCA) and funisitis in women with preterm labor (PTL).

METHODS

In this study, a total of 134 consecutive singleton pregnant women with PTL (at 23+0-34+0 weeks) who delivered preterm (at  < 37 weeks) and from whom CVF samples were collected at admission were retrospectively enrolled. The CVF levels of haptoglobin, interleukin-6/8, kallistatin, lipocalin-2, matrix metalloproteinase (MMP)-8, resistin, S100 calcium-binding protein A8, and serpin A1 were determined using enzyme-linked immunosorbent assay. The placentas were histologically analyzed after delivery.

RESULTS

Multiple logistic regression analyses showed significant associations between elevated CVF interleukin-8 and resistin levels and acute HCA after adjusting for baseline covariates (e.g., gestational age at sampling). CVF haptoglobin, interleukin-6/8, kallistatin, MMP-8, and resistin levels were significantly higher in women with funisitis than in those without, whereas the baseline covariates were similar between the two groups (P > 0.1). The area under the receiver operating characteristic curves of the aforementioned biomarkers ranged from 0.61 to 0.77 regarding each outcome. Notably, HCA risk significantly increased with increasing CVF levels of interleukin-8 and resistin (P for trend  < 0.05).

CONCLUSIONS

Haptoglobin, interleukin-6/8, kallistatin, MMP-8, and resistin were identified as potential inflammatory CVF biomarkers predictive of acute HCA and funisitis in women with PTL. Moreover, the risk severity of acute HCA may be associated with the degree of the inflammatory response in the CVF (particularly based on interleukin-8 levels).

Benefits of Premaquick® Combined Detection of IL-6/Total IGFBP-1/Native IGFBP-1 to Predict Preterm Delivery

We conducted a prospective double-blind study to compare two vaginal diagnostic methods in singleton pregnancies with threatened preterm labor (TPL) at the University Hospital of Clermont-Ferrand (France) from August 2018 to December 2020. Our main objective was to compare the diagnostic capacity at admission, in terms of positive predictive value (PPV) and negative predictive value (NPV), of Premaquick® (combined detection of IL-6/total IGFBP-1/native IGFBP-1) and QuikCheck fFN™ (fetal fibronectin) for delivery within 7 days in cases of TPL. We included 193 patients. Premaquick® had a sensitivity close to 89%, equivalent to QuikCheck fFN™, but a higher statistical specificity of 49.5% against 38.6% for QuikCheck fFN™. We found no superiority of Premaquick® over QuickCheck fFN™ in terms of PPV (6.6% vs. 7.9%), with NPV being equivalent in predicting childbirth within 7 days in cases of TPL (98.6% vs. 98.9%). Nevertheless, the combination of positive native and total IGFBP-1 and the combination of all three positive markers were associated with a higher PPV. Our results, though non-significant, support this combined multiple-biomarker approach to improve testing in terms of predictive values.

Inflammatory Changes and Composition of Collagen during Cervical Ripening in Cows

Dystocia and stillbirths in cows pose a high risk of loss of both dams and fetuses, thereby resulting in high economic losses. One of the causes of these problems is birth canal abnormalities. Thus, to prevent these occurrences, it is necessary to understand the mechanisms underlying cervical ripening. Although physiological inflammatory responses and changes in collagen composition have been reported in humans and mice, related information is scarce for cows. We observed inflammatory changes and changes in the collagen composition in the cervix from late pregnancy to parturition to clarify some of the physiological changes associated with cervical ripening during normal calving in cows. Cervical mucus and tissue samples were collected from 41 Japanese Black cows at 200, 230, and 260 days of gestation and at 7-day intervals thereafter until parturition. The percentage of polymorphonuclear neutrophils (PMN%) in the mucus was calculated, and interleukin (IL)-8 concentration was determined by enzyme-linked immunosorbent assay. Blood samples were collected from the jugular vein, and leukocyte counts were determined. Picrosirius red-stained cervical tissue specimens were observed under a polarizing microscope, and the percentage of type I and type III collagen areas in the cervical tissue were calculated. The PMN% in cervical mucus was lowest at 200 days gestation (12−13 weeks before delivery), significantly increased 5 weeks before (21.7 ± 0.04), and was highest 1 week before calving (50.9 ± 0.04). IL-8 levels were increased at 295 days compared with those at 200 days of pregnancy (p < 0.05). No significant changes were observed in the white blood cell counts. The percentage of type I collagen in the cervical tissue reached a maximum (91.4 ± 0.02%) on day 200, significantly decreased after 274 days (3 weeks before calving), and continued to decrease thereafter until the week of parturition. There was no significant change in type III collagen levels. The results suggest that cervical ripening progresses when PMNs begin to infiltrate the cervix at around 260 days of gestation (5−4 weeks before parturition), IL-8, which increases at the end of pregnancy, mobilizes PMNs, and enhances inflammation, and that type I collagen changes are useful as an indicator of cervical ripening.

Progesterone: A Unique Hormone with Immunomodulatory Roles in Pregnancy

Progesterone is well known for its numerous endocrinologic roles in pregnancy but is also endowed with fascinating immunomodulatory capabilities. It can downregulate the induction of inflammatory reactions, the activation of immune cells and the production of cytokines, which are critical mediators of immune responses. These features appear to be critical to the success of pregnancy, given the ability of maternal immune reactivity to interfere with pregnancy and to contribute to several pregnancy complications. This review summarizes the contribution of maternal immune effectors in general, and cytokines in particular, to pregnancy complications such as recurrent miscarriage, pre-eclampsia and preterm labor; it describes the promise offered by supplementation with progesterone and the oral progestogen dydrogesterone, as well as the progesterone-induced blocking factor in the prevention and/or treatment of these serious complications.

Maternal H-antigen secretor status is an early biomarker for potential preterm delivery

OBJECTIVE

Pre-pregnancy or first trimester biomarkers predicting preterm delivery are lacking. The purpose of this study was to determine whether maternal H-antigen (secretor status) is a potential biomarker for preterm delivery.

METHODS

This cohort study examined maternal saliva samples and birth data gathered by the National Children's Study Vanguard pilot phase (2009-2014) and included 300 women who were ≥18 years old and provided birth data and saliva samples. The maternal secretor status phenotype was determined by quantifying H-antigen in saliva using enzyme-linked immunoassay. Mothers were stratified by secretor status and multivariable analysis estimated adjusted associations with preterm delivery.

RESULTS

Maternal lack of H-antigen production was an independent risk factor for preterm delivery after adjusting for known confounders (aOR 4.53; 95% CI: 1.74, 11.81; P = 0.002).

CONCLUSIONS

Maternal H-antigen may be a biomarker identifying women at-risk for preterm delivery. Prospective cohort studies validating these findings are needed.

Small-volume detection: platform developments for clinically-relevant applications

Biochemical analysis of human body fluids is a frequent and fruitful strategy for disease diagnosis. Point-of-care (POC) diagnostics offers the tantalizing possibility of providing rapid diagnostic results in non-laboratory settings. Successful diagnostic testing using body fluids has been reported on in the literature; however, small-volume detection devices, which offer remarkable advantages such as portability, inexpensiveness, capacity for mass production, and tiny sample volume requirements have not been thoroughly discussed. Here, we review progress in this research field, with a focus on developments since 2015. In this review article, we provide a summary of articles that have detailed the development of small-volume detection strategies using clinical samples over the course of the last 5 years. Topics covered include small-volume detection strategies in ophthalmology, dermatology or plastic surgery, otolaryngology, and cerebrospinal fluid analysis. In ophthalmology, advances in technology could be applied to examine tear or anterior chamber (AC) fluid for glucose, lactoferrin, interferon, or VEGF. These approaches could impact detection and care for diseases including diabetic mellitus, dry-eye disease, and age-related maculopathy. Early detection and easy monitoring are critical approaches for improving overall care and outcome. In dermatology or plastic surgery, small-volume detection strategies have been applied for passive or interactive wound dressing, wound healing monitoring, and blister fluid analysis for autoimmune disease diagnosis. In otolaryngology, the analysis of nasal secretions and mucosa could be used to differentiate between allergic responses and infectious diseases. Cerebrospinal fluid analysis could be applied in neurodegenerative diseases, central neural system infection and tumor diagnosis. Other small-volume fluids that have been analyzed for diagnostic and monitoring purposes include semen and cervico-vaginal fluids. We include more details regarding each of these fluids, associated collection and detection devices, and approaches in our review.

Adiponectin as a Potential Biomarker for Pregnancy Disorders

Adiponectin is an adipocyte-derived hormone that plays a critical role in energy homeostasis, mainly attributed to its insulin-sensitizing properties. Accumulating studies have reported that adiponectin concentrations are decreased during metabolic diseases, such as obesity and type 2 diabetes, with an emerging body of evidence providing support for its use as a biomarker for pregnancy complications. The identification of maternal factors that could predict the outcome of compromised pregnancies could act as valuable tools that allow the early recognition of high-risk pregnancies, facilitating close follow-up and prevention of pregnancy complications in mother and child. In this review we consider the role of adiponectin as a potential biomarker of disorders associated with pregnancy. We discuss common disorders associated with pregnancy (gestational diabetes mellitus, preeclampsia, preterm birth and abnormal intrauterine growth) and highlight studies that have investigated the potential of adiponectin to serve as biomarkers for these disorders. We conclude the review by recommending strategies to consider for future research.

Secretory leukocyte protease inhibitor and progranulin as possible regulators of cervical remodeling in pregnancy

Secretory leukocyte protease inhibitor (SLPI) and progranulin (PGRN) are secretory proteins with an anti-inflammatory property. Their involvement in cervical remodeling in pregnant uterus is not yet elucidated. Thus, this study aimed to explore the significance of SLPI and PGRN in the maintenance of pregnancy by investigating the factors associated with their expression levels at the cervix. Concentrations of SLPI and PGRN proteins were measured in cervical mucus samples collected from asymptomatic pregnant women at 24-26 weeks of gestation (n = 166). The concentrations of those molecules were analyzed with clinical parameters related to risk for preterm delivery (PD). In pregnant mice, we evaluated the effect of lipopolysaccharide-induced inflammation and progesterone effect modulation on cervical mRNA expression of SLPI and PGRN. The cervical PGRN level was significantly lower in women with short cervix (<35 mm) and with a history of threatened PD. In women with short cervix, cervical SLPI concentrations were positively correlated with inflammatory cytokines, interleukin-6 (R² = 0.75) and interleukin-8 (R² = 0.71). In pregnant mice, cervical mRNA expressions of PGRN and SLPI were increased in response to progesterone supplementation and were suppressed by a progesterone antagonist, mifepristone. Lipopolysaccharide-induced inflammation caused remarkable upregulation in cervical SLPI mRNA level but not in PGRN. Progesterone and local inflammation are the factors controlling expression levels of PGRN and SLPI at the cervix. The observed relationship of PGRN and SLPI levels in the cervical mucus with PD-related clinical parameters supports that those anti-inflammatory molecules possibly play a significant role in appropriate regulation of cervical remodeling.

Complement and other immune-related factors in cervicovaginal fluid associated with intra-amniotic infection/inflammation and spontaneous preterm delivery in women with preterm labor

PURPOSE

To investigate whether complement and other immune-related proteins in cervicovaginal fluid (CVF) can predict intra-amniotic infection and/or inflammation (IAI) and spontaneous preterm delivery (SPTD, < 34.0 weeks) in women with preterm labor (PTL) and to compare the predictive abilities of these biomarkers with that of amniotic fluid (AF) white blood cells (WBCs).

METHODS

We designed a retrospective cohort study of 145 women with PTL at 23.0-33.6 weeks who underwent amniocentesis. AF was cultured and assayed for WBC count and interleukin-6 (IL-6). CVF samples were obtained at the time of amniocentesis. CVF was assayed for complement C3a and C5a, IGFBP-1, and MMP-9 by ELISA.

RESULTS

In the multivariate analysis, elevated CVF levels of C5a and IGFBP-1 were significantly associated with IAI and SPTD at < 34 weeks, while those of C3a were associated with IAI, but not SPTD, even after adjusting for other baseline confounders. For C3a, C5a, and IGFBP-1 in the CVF, area under the curve (AUC) values were statistically similar to that of AF WBCs for detecting IAI, whereas these CVF biomarkers had similar or higher AUC values than AF WBCs for predicting SPTD at < 34 weeks. However, univariate analysis showed no significant correlation between high CVF MMP-9 and IAI or SPTD at < 34 weeks.

CONCLUSIONS

In women with PTL, the CVF levels of C3a, C5a, and IGFBP-1 may be useful as novel non-invasive predictors of IAI and SPTD at < 34 weeks. These biomarkers (especially IGFBP-1) have similar or better diagnostic performance compared to AF WBCs.

A Protein Microarray Analysis of Plasma Proteins for the Prediction of Spontaneous Preterm Delivery in Women with Preterm Labor

We aimed to identify novel biomarkers in maternal plasma that predict spontaneous preterm delivery (SPTD) in women with preterm labor (PTL) using an antibody microarray and to develop the best prediction model for SPTD based on these biomarkers in combination with clinical and ultrasound factors. This retrospective cohort study included 215 women with singleton pregnancies and PTL (23-33 weeks) who gave plasma samples. In a nested case-control study design, plasma proteomes from SPTD (case subjects, n = 15) and term delivery (control subjects, n = 15) groups were differentially profiled using a membrane-based antibody microarray. Six candidate biomarkers of interest were validated by enzyme-linked immunosorbent assay (ELISA) in the total cohort (n = 215). Cervical lengths were also measured. The primary outcome measure was SPTD within 48 h after sampling. Twenty of the molecules studied displayed significant intergroup differences. Validation by ELISA confirmed significantly higher levels of plasma endostatin and lipopolysaccharide binding protein (LBP) in women who had SPTD within 48 h than in those delivering after 48 h. However, plasma macrophage inflammatory protein (MIP)-1α levels were significantly lower in women who delivered within 48 h. A combined model was developed to predict SPTD within 48 h using a stepwise regression procedure, which included plasma endostatin and LBP levels, nulliparity, and cervical length (area under the curve = 0.920). Plasma LBP, endostatin, and MIP-1α are potential new biomarkers for predicting imminent SPTD and a combined noninvasive model based on these biomarkers and clinical and ultrasound factors can accurately predict imminent SPTD in women with PTL.

Cervicovaginal Fluid Protein Microarray for Detection of Microbial Invasion of the Amniotic Cavity in Preterm Labor

We aimed to identify cervicovaginal fluid (CVF) biomarkers that can detect microbial invasion of the amniotic cavity (MIAC) in women with preterm labor (PTL) with an antibody microarray and to develop the best combined model for detection of MIAC using these biomarkers in combination with conventional clinical variables. This retrospective cohort study included 168 singleton pregnant women with PTL (23-34 weeks) who underwent amniocentesis. AF was cultured, and CVF samples were obtained at the time of amniocentesis. An antibody microarray was used to analyze the CVF proteome (n = 40). The validation of four candidate biomarkers of interest was performed by enzyme-linked immunosorbent assay (ELISA) in the final cohort (n = 168). For comparison with candidate markers, CVF IL-6 concentration was also measured. Twenty-seven molecules studied exhibited intergroup differences. Validation by ELISA confirmed significantly higher levels of CVF DKK3, M-CSF, and TIMP-1, but not of IGFBP-2, independent of gestational age, in CVF of women with MIAC. The area under the curve (AUC) of DKK3, M-CSF, and TIMP-1 from CVF was not significantly different from the AUC of IL-6 from CVF for detecting MIAC in women with PTL. By using a stepwise regression analysis, a combined detection model was developed, which included the CVF M-CSF, TIMP-1, and gestational age at sampling (AUC = 0.823). An antibody microarray identified useful biomarkers (DKK3, M-CSF, and TIMP-1) in CVF for detection of MIAC, and a combined model including these biomarkers and gestational age can accurately detect MIAC in women with PTL.

Neutrophil elastase in cervical fluid in women with short cervical length

OBJECTIVE

The aim of the study was to determine the relationships between short cervical length (CL) and levels of cervical fluid neutrophil elastase (NE), secretory leukocyte protease inhibitor (SLPI), and interleukin 8 (IL-8) in the second trimester of pregnancy of women who underwent ultrasound-indicated cervical cerclage.

MATERIALS AND METHODS

CL of <25 mm or cervical funneling were included in the short CL group (n = 26) and the normal CL group (n = 22) included women who had CL of ≥25 mm and had no cervical funneling in women between 17 + 0 and 24 + 6 weeks of gestation. Levels of NE, SLPI, and IL-8 were measured by using enzyme-linked immunosorbent assay kits. Mann-Whitney U tests and Spearman's correlation analysis were used for statistical analyses.

RESULTS

Compared with the normal CL group, the short CL group had significantly higher median NE levels (P < 0.001) and higher, though not significant, median IL-8 levels by approximately three times (2107.0 vs. 798.3 pg/mL, P = 0.132). The median SLPI levels in cervical fluid was similar between the two groups (107.6 vs. 103.2 ng/mL, P = 0.499). Short CL had a significant correlations with cervical fluid NE levels (r = -0.475, P = 0.001).

CONCLUSION

Increased cervical fluid NE associated with cervical shortening in second trimester of pregnancy, whereas cervical fluid SLPI had constant levels.

Prediction of Preterm Birth: Maternal Characteristics, Ultrasound Markers, and Biomarkers: An Updated Overview

There is not a single or combined screening method for preterm birth with high sensitivity which will truly identify the women at risk for preterm birth while also with high specificity to prevent unnecessary interventions and high treatment costs. Measurement of cervical length is the most cost-effective method that is used in clinical practice. Bedside tests have also been developed for detecting markers like fetal fibronectin, insulin-like growth factor binding protein-1 (IGFBP-1), interleukin-6, and placental alpha-macroglobulin-1. Taking the maternal history, health condition, and sociodemographical factors into consideration is recommended. Ultrasound markers apart from cervical length measurements as uterocervical angle and placental strain ratio are studied. Investigations on metabolomics, proteomics, and microRNA profiling have brought a new aspect on this subject. Maybe in the future, with clear identification of women at true risk for preterm birth, development of more effective preventive strategies will not be unfeasible.

Vitamin D-binding protein in cervicovaginal fluid as a non-invasive predictor of intra-amniotic infection and impending preterm delivery in women with preterm labor or preterm premature rupture of membranes

Objective

To determine whether vitamin D-binding protein (VDBP) in cervicovaginal fluid (CVF) is independently predictive of intra-amniotic infection and imminent spontaneous preterm delivery (SPTD, delivery within 48 hours) in women with preterm labor with intact membranes (PTL) or preterm premature rupture of membranes (PPROM).

Method

This was a single-center retrospective cohort study. CVF samples for VDBP assays were obtained along with serum C-reactive protein (CRP) levels immediately after amniocentesis in consecutive women with PTL (n = 148) or PPROM (n = 103) between 23.0 and 34.0 weeks of gestation. VDBP levels in CVF were determined by enzyme-linked immunosorbent assay kits. The primary outcome measures were intra-amniotic infection [defined as positive amniotic fluid (AF) culture] and SPTD within 48 hours after sampling.

Results

In the multivariable analysis, elevated VDBP levels in CVF samples of PTL women were significantly associated with intra-amniotic infection and imminent preterm delivery, even after adjusting for potential confounders (e.g., gestational age at sampling, parity, and serum CRP). However, these relationships were not found in women with PPROM. In women with PTL, the areas under receiver operating characteristic curves of CVF VDBP level for predicting intra-amniotic infection and imminent preterm delivery were 0.66 and 0.71, with cut-off values of 1.76 μg/mL (sensitivity of 64.3% and specificity of 78.4%) and 1.37 μg/mL (sensitivity of 65.4% and specificity of 72.6%), respectively. The CVF VDBP levels were significantly higher in women with PPROM than in those with PTL.

Conclusions

VDBP in the CVF independently predicts intra-amniotic infection and imminent preterm delivery in women with PTL, whereas in women with PPROM, an elevated VDBP level in CVF is not associated with increased risks of these two outcome variables.

Impact of Pregnancy History and 17-Hydroxyprogesterone Caproate on Cervical Cytokines and Matrix Metalloproteinases

OBJECTIVE

 The objective of this study was to evaluate the impact of pregnancy history and 17-hydroxyprogesterone caproate (17-OHPC) treatment on cervical fluid cytokines and matrix metalloproteinases (MMPs).

STUDY DESIGN

 Cervical fluid was obtained between 160/7 and 246/7 weeks from women with only prior term births (controls, n = 26), women with one or more prior spontaneous preterm births (SPTBs) choosing to receive 17-OHPC (17-OHPC, n = 24), or to not receive 17-OHPC (refusers, n = 12). Cervical fluid collections were repeated 2, 4, and 8 weeks after the first sample and concentrations of MMPs and cytokines were measured by multiplex immune assay.

RESULTS

 Among women whose earliest prior delivery occurred between 16 and 23 weeks, cervical fluid concentration of interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α at baseline were significantly elevated when compared with cervical cytokines of women whose earliest delivery occurred between 32 and 36 weeks (relative risk ratio was 3.37 for IL-6 [95% confidence interval, CI, 1.08-10.53, p < 0.05], 2.81 for IL-10 [95% CI, 1.39-5.70, p < 0.05], and 6.34 for TNF-α [95% CI, 2.19-18.68, p < 0.001]). Treatment with 17-OHPC had no significant impact on these cytokines.

CONCLUSION

 The cervical fluid of women with a history of an early prior SPTB is characterized by inflammation that is unaffected by 17-OHPC.

Comparison of Serum and Cervical Cytokine Levels throughout Pregnancy between Preterm and Term Births

Objective  To assess differences in cytokine levels in cervicovaginal fluid (CVF) and serum across trimesters between women with preterm births (PTBs) and full-term births. Study Design  This multicenter study enrolled 302 women with a singleton gestation. CVF and serum cytokines, interleukin 1α (IL-1α), IL-1β, IL-6, IL-8, IL-10, C-reactive protein (CRP), tumor necrosis factor (TNF)-α, and matrix metalloproteinase (MMP)-8, were measured. Women with at least one cytokine assessment and noted PTB status in their medical record were retained in the study ( N  = 272). Data were analyzed using mixed modeling (main effects of PTBs and time/trimester). Results  For the CVF values of IL-6, IL-8, IL-10, TNF-α, and CRP, and serum MMP-8, those who delivered preterm had significantly higher values than the full-term group regardless of trimester. For the serum values of IL-1β, IL-6, and TNF-α, those delivering preterm had significantly lower values than those delivering full-term regardless of trimester. For IL-1β in CVF, the cytokine was significantly higher in the PTB group for second and third trimesters only, relative to the full-term group. Conclusion  For each CVF cytokine that differed by birth status, values were higher for PTB than term, averaged over trimester. Numerous cytokine profiles varied across trimesters in women delivering term versus preterm in both CVF and serum.

Non-invasive prediction of preterm birth in women with cervical insufficiency or an asymptomatic short cervix (≤25 mm) by measurement of biomarkers in the cervicovaginal fluid

OBJECTIVE

To determine whether various proteins in the cervicovaginal fluid (CVF) known to be involved in immune regulation, alone or in combination with clinical risk factors, can predict spontaneous preterm delivery (SPTD) in women with cervical insufficiency or a short cervix (≤25 mm).

METHODS

This retrospective cohort study included 62 asymptomatic women with cervical insufficiency (n = 27) or an asymptomatic short cervix (n = 35) at 18-27 weeks. CVF swab samples were taken for assays of vitamin D binding protein (VDBP), interleukin (IL)-8, matrix metalloproteinases (MMP)-9, tissue inhibitor of metalloproteinases (TIMP)-1, and Dickkopf-related protein 3 (DKK3) before cervical examination, and maternal blood was collected for the determination of the C-reactive protein (CRP) level. The primary outcome measurement was SPTD at <32 weeks of gestation. Logistic regression analysis and receiver operating characteristic curves were used for the statistical analyses.

RESULTS

The rate of SPTD at <32 weeks was 40.3% (25/62). The CVF levels of VDBP, TIMP-1, and DKK3, but not IL-8 and MMP-9, were significantly higher in the women who had SPTD at <32 weeks than in those who did not deliver spontaneously at <32 weeks. The women who had SPTD at <32 weeks had a significantly more advanced cervical dilatation at presentation and a higher level of serum CRP. Using the stepwise regression analysis, a prediction model was developed by combining various proteins in the CVF and clinical factors, resulting in the inclusion of cervical dilatation, CVF VDBP, and use of corticosteroids (area under curve, 0.909).

CONCLUSIONS

In women with cervical insufficiency or a short cervix, VDBP, TIMP-1, and DKK3 in the CVF may be useful as non-invasive predictors of SPTD at <32 weeks. A combination of these markers and clinical factors appears to improve the predictability of SPTD compared with the markers alone.

An artificial neural network prediction model of congenital heart disease based on risk factors: A hospital-based case-control study

An artificial neural network (ANN) model was developed to predict the risks of congenital heart disease (CHD) in pregnant women.This hospital-based case-control study involved 119 CHD cases and 239 controls all recruited from birth defect surveillance hospitals in Hunan Province between July 2013 and June 2014. All subjects were interviewed face-to-face to fill in a questionnaire that covered 36 CHD-related variables. The 358 subjects were randomly divided into a training set and a testing set at the ratio of 85:15. The training set was used to identify the significant predictors of CHD by univariate logistic regression analyses and develop a standard feed-forward back-propagation neural network (BPNN) model for the prediction of CHD. The testing set was used to test and evaluate the performance of the ANN model. Univariate logistic regression analyses were performed on SPSS 18.0. The ANN models were developed on Matlab 7.1.The univariate logistic regression identified 15 predictors that were significantly associated with CHD, including education level (odds ratio  = 0.55), gravidity (1.95), parity (2.01), history of abnormal reproduction (2.49), family history of CHD (5.23), maternal chronic disease (4.19), maternal upper respiratory tract infection (2.08), environmental pollution around maternal dwelling place (3.63), maternal exposure to occupational hazards (3.53), maternal mental stress (2.48), paternal chronic disease (4.87), paternal exposure to occupational hazards (2.51), intake of vegetable/fruit (0.45), intake of fish/shrimp/meat/egg (0.59), and intake of milk/soymilk (0.55). After many trials, we selected a 3-layer BPNN model with 15, 12, and 1 neuron in the input, hidden, and output layers, respectively, as the best prediction model. The prediction model has accuracies of 0.91 and 0.86 on the training and testing sets, respectively. The sensitivity, specificity, and Yuden Index on the testing set (training set) are 0.78 (0.83), 0.90 (0.95), and 0.68 (0.78), respectively. The areas under the receiver operating curve on the testing and training sets are 0.87 and 0.97, respectively.This study suggests that the BPNN model could be used to predict the risk of CHD in individuals. This model should be further improved by large-sample-size research.

Myometrial cytokines and their role in the onset of labour

Human labour is an inflammatory event, physiologically driven by an interaction between hormonal and mechanical factors and pathologically associated with infection, bleeding and excessive uterine stretch. The initiation and communicators of inflammation is still not completely understood; however, a key role for cytokines has been implicated. We summarise the current understanding of the nature and role of cytokines, chemokines and hormones and their involvement in signalling within the myometrium particularly during labour.