Accuracy of a combined insulin-like growth factor-binding protein-1/interleukin-6 test (Premaquick) in predicting delivery in women with threatened preterm labor

Local vaginal bioelectrical impedance can predict preterm delivery in mice

Preterm birth is a serious pregnancy complication that affects neonatal mortality, morbidity, and long-term neurological prognosis. Predicting spontaneous preterm delivery (PTD) is important for its management. While excluding the risk of PTD is important, identifying women at high risk of PTD is imperative for medical intervention. Currently used PTD prediction parameters in clinical practice have shown high negative predictive values, but low positive predictive values. We focused on sulfated and sialylated glycocalyx changes in the uterus and vagina prior to the onset of parturition and explored the potential of electrophysiological detection of these changes as a PTD prediction parameter with a high positive predictive value. In vivo local vaginal bioelectrical impedance (VZ) was measured using two different mouse PTD models. PTD was induced in ICR mice through the subcutaneous injection of mifepristone or local intrauterine injection of lipopolysaccharide (LPS). The PTD rates were 100% and 60% post-administration of mifepristone (16-20 h, n = 4) and LPS (12-24 h, n = 20), respectively. The local VZ values (15 and 10 h after mifepristone or LPS treatment, respectively) were significantly lower in the PTD group than in the non-PTD group. Receiver operator characteristic (ROC) curve analysis of VZ at 125 kHz as a predictor of PTD showed an area under the ROC curve of 1.00 and 0.77 and positive predictive values of 1.00 and 0.86, for the mifepristone and LPS models, respectively, suggesting that local VZ value can predict PTD. Histological examination of the LPS-treated model 6 h post-treatment revealed increased expression of sulfomucins and/or sulfated proteoglycans and sialomucins in the cervical epithelium, cervical stroma and vaginal stroma. In conclusion, local VZ values can determine sulfated and sialylated glycocalyx alterations within the uterus and vagina and might be a useful PTD prediction parameter.

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.

A randomized clinical trial of Premaquick biomarkers versus transvaginal cervical length for pre-induction cervical assessment at term among pregnant women

Objectives

To compare Premaquick biomarkers (combined insulin-like growth-factor binding protein 1 and interleukin-6) and cervical length measurement via transvaginal ultrasound for pre-induction cervical evaluation at term among pregnant women.

Methods

A randomized clinical trial of consenting pregnant women at the Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria. The women were randomized equally into Premaquick group (n = 36) and transvaginal ultrasound group (n = 36). The cervix was adjudged 'ripe' if the Premaquick test was positive or if the trans-vaginal measured cervical length was less than 28 mm. The primary outcome measures were the proportions of women who needed prostaglandin analogue for cervical ripening and the proportion that achieved vaginal delivery after induction of labour. The trial was registered in Pan African clinical trial registry (PACTR) registry with approval number PACTR202001579275333.

Results

The baseline characteristics were similar between the two groups (p > 0.05). There was no statistically significant difference between the two groups in terms of proportion of women that required prostaglandins for pre-induction cervical ripening (41.7 versus 47.2%, p = 0.427), vaginal delivery (77.8 versus 80.6%, p = 0.783), mean induction to delivery interval (22.9 ± 2.81 h versus 24.04 ± 3.20 h, p = 0.211), caesarean delivery (22.2 versus 19.4%, p = 0.783), proportion of neonate with birth asphyxia (8.30 versus 8.30%, p = 1.00) and proportion of neonate admitted into special care baby unit (16.7 versus 13.9%, p = 0.872). Subgroup analysis of participants with 'ripe' cervix at initial pre-induction assessment showed that the mean induction to active phase of labour interval and mean induction to delivery interval were significantly shorter in Premaquick than transvaginal ultrasound group.

Conclusion

Pre-induction cervical assessment at term with either Premaquick biomarkers or transvaginal ultrasound for cervical length is effective, objective and safe with similar and comparable outcome. However, when compared with women with positive transvaginal ultrasound at initial assessment, women with positive Premaquick test at initial assessment showed a significantly shorter duration of onset of active phase of labour and delivery of baby following induction of labour.

Development and validation of a transcriptomic signature-based model as the predictive, preventive, and personalized medical strategy for preterm birth within 7 days in threatened preterm labor women

Preterm birth (PTB) is the leading cause of neonatal death. The essential strategy to prevent PTB is the accurate identification of threatened preterm labor (TPTL) women who will have PTB in a short time (< 7 days). Here, we aim to propose a clinical model to contribute to the effective prediction, precise prevention, and personalized medical treatment for PTB < 7 days in TPTL women through bioinformatics analysis and prospective cohort studies. In this study, the 1090 key genes involved in PTB < 7 days in the peripheral blood of TPTL women were ascertained using WGCNA. Based on this, the biological basis of immune-inflammatory activation (e.g., IFNγ and TNFα signaling) as well as immune cell disorders (e.g., monocytes and Th17 cells) in PTB < 7 days were revealed. Then, four core genes (JOSD1, IDNK, ZMYM3, and IL1B) that best represent their transcriptomic characteristics were screened by SVM and LASSO algorithm. Therefore, a prediction model with an AUC of 0.907 was constructed, which was validated in a larger population (AUC = 0.783). Moreover, the predictive value (AUC = 0.957) and clinical feasibility of this model were verified through the clinical prospective cohort we established. In conclusion, in the context of Predictive, Preventive, and Personalized Medicine (3PM), we have developed and validated a model to predict PTB < 7 days in TPTL women. This is promising to greatly improve the accuracy of clinical prediction, which would facilitate the personalized management of TPTL women to precisely prevent PTB < 7 days and improve maternal-fetal outcomes.

A diagnostic profile on the PartoSure test

Introduction: Preterm birth (PTB) is common, occurring in over 10% of all live births globally, and is increasing worldwide. The limitations of traditional biomarkers of PTB, such as fetal fibronectin (fFN) and phosphorylated insulin-like growth factor-binding protein-1 (phIGFBP-1) have been well demonstrated in the literature. Therefore, augmenting clinical assessment with newer biomarkers, such as placental alpha macroglobulin-1 (PAMG-1); PartoSure, has the potential to improve disease monitoring and the best interventions. Areas covered: The present expert opinion evaluates the utility and limitations of PAMG-1; PartoSure as a biomarker for PTB in light of the current literature. Expert opinion: Although fFN, phIGFBP-1 and PAMG-1; PartoSure test had similar negative predictive value (NPV) and negative likelihood ratio (LR-), the PAMG-1; PartoSure test had the highest specificity, positive predictive value (PPV), and positive likelihood ratio (LR+) across all at-risk pregnant women. Although findings of this review may be encouraging, the PartoSure test should not be interpreted as absolute evidence for prediction of PTB. The PartoSure test result should always be used in conjunction with information available from the clinical evaluation of the pregnant woman and other diagnostic procedures such as cervical examination, assessment of uterine activity, and evaluation of other risk factors.

Cervical stitch (cerclage) in combination with other treatments for preventing spontaneous preterm birth in singleton pregnancies

BACKGROUND

Preterm birth (PTB) remains the foremost global cause of perinatal morbidity and mortality. Thus, the prevention of spontaneous PTB still remains of critical importance. In an attempt to prevent PTB in singleton pregnancies, cervical cerclage, in combination with other treatments, has been advocated. This is because, cervical cerclage is an intervention that is commonly recommended in women with a short cervix at high risk of preterm birth but, despite this, many women still deliver prematurely, as the biological mechanism is incompletely understood. Additionally, previous Cochrane Reviews have been published on the effectiveness of cervical cerclage in singleton and multiple pregnancies, however, none has evaluated the effectiveness of using cervical cerclage in combination with other treatments.

OBJECTIVES

To assess whether antibiotics administration, vaginal pessary, reinforcing or second cerclage placement, tocolytic, progesterone, or other interventions at the time of cervical cerclage placement prolong singleton gestation in women at high risk of pregnancy loss based on prior history and/or ultrasound finding of 'short cervix' and/or physical examination. History-indicated cerclage is defined as a cerclage placed usually between 12 and 15 weeks gestation based solely on poor prior obstetrical history, e.g. multiple second trimester losses due to painless dilatation. Ultrasound-indicated cerclage is defined as a cerclage placed usually between 16 and 23 weeks gestation for transvaginal ultrasound cervical length < 20 mm in a woman without cervical dilatation. Physical exam-indicated cerclage is defined as a cerclage placed usually between 16 and 23 weeks gestation because of cervical dilatation of one or more centimetres detected on physical (manual) examination.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) (26 September 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

We included published, unpublished or ongoing randomised controlled trial (RCTs). Studies using a cluster-RCT design were also eligible for inclusion in this review but none were identified. We excluded quasi-RCTs (e.g. those randomised by date of birth or hospital number) and studies using a cross-over design. We also excluded studies that specified addition of the combination therapy after cervical cerclage because the woman subsequently became symptomatic. We included studies comparing cervical cerclage in combination with one, two or more interventions with cervical cerclage alone in singleton pregnancies.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts of all retrieved articles, selected studies for inclusion, extracted data, assessed risk of bias, and evaluated the certainty of the evidence for this review's main outcomes. Data were checked for accuracy. Standard Cochrane review methods were used throughout.

MAIN RESULTS

We identified two studies (involving a total of 73 women) comparing cervical cerclage alone to a different comparator. We also identified three ongoing studies (one investigating vaginal progesterone after cerclage, and two investigating cerclage plus pessary). One study (20 women), conducted in the UK, comparing cervical cerclage in combination with a tocolytic (salbutamol) with cervical cerclage alone in women with singleton pregnancy did not provide any useable data for this review. The other study (involving 53 women, with data from 50 women) took place in the USA and compared cervical cerclage in combination with a tocolytic (indomethacin) and antibiotics (cefazolin or clindamycin) versus cervical cerclage alone - this study did provide useable data for this review (and the study authors also provided additional data on request) but meta-analyses were not possible. This study was generally at a low risk of bias, apart from issues relating to blinding. We downgraded the certainty of evidence for serious risk of bias and imprecision (few participants, few events and wide 95% confidence intervals). Cervical cerclage in combination with an antibiotic and tocolytic versus cervical cerclage alone (one study, 50 women/babies) We are unclear about the effect of cervical cerclage in combination with antibiotics and a tocolytic compared with cervical cerclage alone on the risk of serious neonatal morbidity (RR 0.62, 95% CI 0.31 to 1.24; very low-certainty evidence); perinatal loss (data for miscarriage and stillbirth only - data not available for neonatal death) (RR 0.46, 95% CI 0.13 to 1.64; very low-certainty evidence) or preterm birth < 34 completed weeks of pregnancy (RR 0.78, 95% CI 0.44 to 1.40; very low-certainty evidence). There were no stillbirths (intrauterine death at 24 or more weeks). The trial authors did not report on the numbers of babies discharged home healthy (without obvious pathology) or on the risk of neonatal death.

AUTHORS' CONCLUSIONS

Currently, there is insufficient evidence to evaluate the effect of combining a tocolytic (indomethacin) and antibiotics (cefazolin/clindamycin) with cervical cerclage compared with cervical cerclage alone for preventing spontaneous PTB in women with singleton pregnancies. Future studies should recruit sufficient numbers of women to provide meaningful results and should measure neonatal death and numbers of babies discharged home healthy, as well as other important outcomes listed in this review. We did not identify any studies looking at other treatments in combination with cervical cerclage. Future research needs to focus on the role of other interventions such as vaginal support pessary, reinforcing or second cervical cerclage placement, 17-alpha-hydroxyprogesterone caproate or dydrogesterone or vaginal micronised progesterone, omega-3 long chain polyunsaturated fatty acid supplementation and bed rest.

Combined insulin-like growth factor binding protein-1/interleukin-6 (Premaquick) versus fetal fibronectin for predicting preterm delivery among women with preterm contractions

OBJECTIVES

To compare accuracy between Premaquick (combined test for native insulin-like growth factor binding protein-1 (IGFBP-1), total IGFBP-1, and interleukin-6) and fetal fibronectin (Ffn) in predicting preterm delivery.

METHODS

Prospective study among women at 28-36⁺⁶ gestational weeks with threatened preterm labor attending Federal Medical Center, Owerri, Nigeria, from August 2017 to February 2019. Cervico-vaginal fluids were collected and tested by Premaquick and Ffn tests. The women were followed for 14 days. Sensitivity, specificity, and negative (NPV) and positive (PPV) predictive value for delivery were compared between the tests.

RESULTS

Among 213 women assessed for eligibility, 183 were enrolled and 175 completed the study. The sensitivity, specificity, PPV, NPV, and accuracy of the Premaquick versus Ffn tests were, respectively, 96.3% versus 51.9%, 97.6% versus 98.4%, 89.7% versus 87.5%, 99.2% versus 90.3% and 97.3% versus 90.0% for preterm delivery within 14 days. Ffn had higher specificity (98.5% vs 97.8%; P>0.99), but Premaquick had higher PPV (92.7% vs 90.9%; P>0.99).

CONCLUSION

Both tests seem to have high utility in predicting preterm delivery, but Premaquick showed higher accuracy in terms of sensitivity and PPV. Premaquick might be a feasible alternative to Ffn for predicting preterm delivery among symptomatic women in a low-income setting.

A high concentration of fetal fibronectin in cervical secretions increases the risk of intra-amniotic infection and inflammation in patients with preterm labor and intact membranes

Objective To determine whether the risk of intra-amniotic infection/inflammation and spontaneous preterm delivery (SPTD) varies as a function of the concentration of cervical fetal fibronectin (fFN) in patients with preterm labor and intact membranes. Methods This prospective study included 180 patients with preterm labor and intact membranes who had a sample collected for quantitative fFN measurement and underwent amniocentesis. Amniotic fluid was cultured for aerobic and anaerobic bacteria and genital mycoplasmas. Intra-amniotic inflammation was defined as an amniotic fluid matrix metalloproteinase-8 concentration >23 ng/mL. Results (1) The prevalence of intra-amniotic infection/inflammation and SPTD within 7 days was 32.2% (58/180) and 33.9% (61/178), respectively; (2) The higher the fFN concentration, the greater the risk of intra-amniotic infection/inflammation and SPTD within 7 days (P<0.001, respectively); (3) An fFN concentration 150 ng/mL had a better diagnostic performance than an fFN 50 ng/mL in the identification of intra-amniotic infection/inflammation and SPTD within 7 days; (4) Among the patients with an fFN <50 ng/mL, intra-amniotic infection/inflammation was identified in 7.6% (6/79) of patients and 66.7% (4/6) delivered within 7 days. Conclusion The higher the concentration of fFN, the greater the risk of intra-amniotic infection/inflammation and SPTD in patients with preterm labor and intact membranes.

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.

Cytokines in Preterm Delivery: Proposal of a New Diagnostic Algorithm

Predicting preterm delivery within 7 days is very important for the proper timing of glucocorticosteroid administration. If within 7 days after glucocorticosteroid administration, the delivery does not occur, it remains questionable if repeated glucocorticosteroid therapy results in improved infant respiratory function. Therefore, differentiation of preterm delivery from false preterm delivery is clinically significant. The aim of this study was to create a diagnostic algorithm to distinguish preterm delivery from false preterm delivery on the basis of concentrations of selected cytokines. The study group (n = 622) were patients hospitalized due to threatened preterm delivery. To assess the concentration of cytokines in the serum, we used a multiplex method, which allows simultaneous determination of 13 cytokines. The sets consist of the following cytokines: IGFBP-1, IGFBP-2, BDNF, L-Selectin, E-Selectin, ICAM-1, PECAM, VCAM-1, MIP-1d, MIP-3b, Eotaxin-1, Eotaxin-2, and BLC. In the study group, 67.8% patients had preterm delivery and 32.2% had false preterm delivery. Based on the analysis of cytokine concentrations, a classification tree to distinguish between preterm delivery and false preterm delivery was created. Our findings show the possibility of prediction of preterm delivery with the use of a classification and regression tree of selected cytokine concentration.

Application effect of single balloon catheters in labor induction of pregnant women in late-term pregnancy and their influences on stress and inflammatory responses

This study was designed to evaluate the application effect of single balloon catheters and dinoprostone on promoting cervical ripening of pregnant women in late-term pregnancy and their influences on stress and inflammatory responses. A total of 160 pregnant women with indications of labor induction were included and randomly divided into the control (n=80) and observation (n=80) groups. Patients in the control group received labor induction by administration of dinoprostone at the vaginal vault, while those in the observation group received labor induction by domestic single balloon catheters. Cervical ripening (Bishop score), means of pregnancy, the total stage of labor, maternal and child complications, and Apgar scores of newborn infants at 1 min after delivery between the two groups were compared. At the prenatal and postpartum 12, 24 and 48 h, the levels of cortisol (COR), norepinephrine (NE) and β-endorphin (β-EP), were detected using radioimmunoassay, and those of C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), were measured using enzyme-linked immunosorbent assay (ELISA). Cervical Bishop scores in the two groups after intervention were significantly higher than those before intervention, and the score of the observation group was significantly higher than that of the control group. The difference was statistically significant (P<0.05). In the observation group, the total stage of labor was significantly shortened, the Apgar score of the newborn infant at 1 min after delivery was increased compared with those in the control group, and the differences were statistically significant (P<0.05). The delivery rate of cesarean section in the observation group was lower than that in the control group, the overall incidence rate of perinatal complications was decreased, and the differences were statistically significant (P<0.05). The levels of stress and inflammatory response markers at 12 h after delivery in the two groups reached the peak, and then declined (P<0.05). The levels of stress and inflammatory response markers at each time-point after delivery in the observation group were significantly lower than those in the control group, and the difference was statistically significant (P<0.05). The results showed that the single balloon catheter promotes cervical ripening, improves pregnancy outcomes and reduces the stress and inflammatory responses of pregnant women in late-term pregnancy, and is better than dinoprostone and has better application and promotion values.