Screening to prevent spontaneous preterm birth: systematic reviews of accuracy and effectiveness literature with economic modelling

Home uterine monitoring for detecting preterm labour

BACKGROUND

To reduce the morbidity and mortality associated with preterm birth, home uterine activity monitoring aims for early detection of increased contraction frequency, and early intervention with tocolytic drugs to inhibit labour and prolong pregnancy. However, the effectiveness of such monitoring is disputed.

OBJECTIVES

To determine whether home uterine activity monitoring is effective in improving the outcomes for women and their infants considered to be at high risk of preterm birth, when compared with care that does not include home uterine activity monitoring.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 June 2016), CENTRAL (Cochrane Library 2016, Issue 5), MEDLINE (1966 to 28 June 2016), Embase (1974 to 28 June 2016), CINAHL (1982 to 28 June 2016), and scanned reference lists of retrieved studies.

SELECTION CRITERIA

Randomised control trials of home uterine activity monitoring, with or without patient education programmes, for women at risk of preterm birth, compared with care that does not include home uterine activity monitoring.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risks of bias, extracted data and checked them for accuracy. We did not attempt to contact authors to resolve queries. We assessed the evidence using the GRADE approach.

MAIN RESULTS

There were 15 included studies (6008 enrolled participants); 13 studies contributed data. Women using home uterine monitoring were less likely to experience preterm birth at less than 34 weeks (risk ratio (RR) 0.78, 95% confidence interval (CI) 0.62 to 0.99; three studies, 1596 women; fixed-effect analysis) (GRADE high). This difference was not evident when we carried out a sensitivity analysis, restricting the analysis to studies at low risk of bias based on study quality (RR 0.75, 95% CI 0.57 to 1.00; one study, 1292 women). There was no difference in the rate of perinatal mortality (RR 1.22, 95% CI 0.86 to 1.72; two studies, 2589 babies) (GRADE low).There was no difference in the number of preterm births at less than 37 weeks (average RR 0.85, CI 0.72 to 1.01; eight studies, 4834 women; random-effects, Tau2 = 0.03, I2 = 68%) (GRADE very low). Infants born to women using home uterine monitoring were less likely to be admitted to neonatal intensive care unit (average RR 0.77, 95% CI 0.62 to 0.96; five studies, 2367 babies; random-effects, Tau2 = 0.02, I2 = 32%) (GRADE moderate). This difference was not maintained when we restricted the analysis to studies at low risk of bias (RR 0.86, 95% CI 0.74 to 1.01; one study, 1292 babies). Women using home uterine monitoring made more unscheduled antenatal visits (mean difference (MD) 0.48, 95% CI 0.31 to 0.64; two studies, 1994 women) (GRADE moderate). Women using home uterine monitoring were also more likely to have prophylactic tocolytic drug therapy (average RR 1.21, 95% CI 1.01 to 1.45; seven studies, 4316 women; random-effects, Tau2 = 0.03, I2 = 62%), but this difference was no longer evident when we restricted the analysis to studies at low risk of bias (average RR 1.22, 95% CI 0.90 to 1.65; three studies, 3749 women; random-effects, Tau2 = 0.05, I2 = 76%) (GRADE low). The number of antenatal hospital admissions did not differ between home groups (RR 0.91, 95% CI 0.74 to 1.11; three studies, 1494 women (GRADE low)). We found no data on maternal anxiety or acceptability.

AUTHORS' CONCLUSIONS

Home uterine monitoring may result in fewer admissions to a neonatal intensive care unit but in more unscheduled antenatal visits and tocolytic treatment; the level of evidence is generally low to moderate. Important group differences were not evident when we undertook sensitivity analysis using only trials at low risk of bias. There is no impact on maternal and perinatal outcomes such as perinatal mortality or incidence of preterm birth.

Assessing the Expected Value of Research Studies in Reducing Uncertainty and Improving Implementation Dynamics

BACKGROUND

With low implementation of cost-effective health technologies being a problem in many health systems, it is worth considering the potential effects of research on implementation at the time of health technology assessment. Meaningful and realistic implementation estimates must be of dynamic nature.

OBJECTIVE

To extend existing methods for assessing the value of research studies in terms of both reduction of uncertainty and improvement in implementation by considering diffusion based on expert beliefs with and without further research conditional on the strength of evidence.

METHODS

We use expected value of sample information and expected value of specific implementation measure concepts accounting for the effects of specific research studies on implementation and the reduction of uncertainty. Diffusion theory and elicitation of expert beliefs about the shape of diffusion curves inform implementation dynamics. We illustrate use of the resulting dynamic expected value of research in a preterm birth screening technology and results are compared with those from a static analysis.

RESULTS

Allowing for diffusion based on expert beliefs had a significant impact on the expected value of research in the case study, suggesting that mistakes are made where static implementation levels are assumed. Incorporating the effects of research on implementation resulted in an increase in the expected value of research compared to the expected value of sample information alone.

CONCLUSIONS

Assessing the expected value of research in reducing uncertainty and improving implementation dynamics has the potential to complement currently used analyses in health technology assessments, especially in recommendations for further research. The combination of expected value of research, diffusion theory, and elicitation described in this article is an important addition to the existing methods of health technology assessment.

Quantitative Fetal Fibronectin at 18 Weeks of Gestation to Predict Preterm Birth in Asymptomatic High-Risk Women

OBJECTIVE

To compare quantitative fetal fibronectin measurement from 18 to 21 weeks of gestation to measurement at 22-27 weeks of gestation for the prediction of spontaneous preterm birth.

METHODS

In a prospective cohort study, we studied the accuracy of cervicovaginal fluid quantitative fetal fibronectin concentrations measured between 18 0/7 weeks of gestation and 21 6/7 weeks of gestation in high-risk asymptomatic women to predict spontaneous preterm birth before 34 weeks of gestation. Predefined fibronectin thresholds were 10 or greater, 50 or greater, and 200 ng/mL or greater. Diagnostic accuracy of the early test (n=898) was compared with the standard test performed between 22 0/7 and 27 6/7 weeks of gestation (n=691) in the same cohort. Subgroup analysis was performed according to cervical length measurement.

RESULTS

Of 898 women, 8.7% delivered spontaneously before 34 weeks of gestation. Only 3.8% of the women with concentrations less than 10 ng/mL (65% of test results) delivered before 34 weeks of gestation. A concentration threshold of 10 ng/mL measured at 18 and 22 weeks of gestation had comparably high sensitivity (early 0.71, 95% confidence interval 0.60-0.81; standard 0.76, 0.63-0.87) and negative predictive value (early 0.96, 0.94-0.98; standard 0.97, 0.95-0.99) for delivery before 34 weeks of gestation. Specificity was also comparable (early 0.69, 0.65-0.72; standard 0.70, 0.66-0.74). A threshold of 200 ng/mL had high specificity (early 0.96, 0.94-0.98; standard 0.96, 0.94-0.97) with lower sensitivity (early 0.26, 0.17-0.37; standard 0.35, 0.22-0.49). Consideration of cervical length strengthened prediction.

CONCLUSION

Quantitative cervicovaginal fetal fibronectin measured from 18 to 21 weeks of gestation has similar predictive value as measurement at 22-27 weeks of gestation for prediction of spontaneous preterm birth. Low fibronectin concentrations are associated with spontaneous preterm birthrates approaching population background levels.

Do serial measurements of cervical length improve the prediction of preterm birth in asymptomatic women with twin gestations?

BACKGROUND

Cervical length at midtrimester is a powerful predictor of preterm birth in twin gestations. However, given the fact that, in some cases, cervical shortening may become evident only later during the second trimester, it seems reasonable that serial monitoring of cervical length may improve the detection of preterm birth in women with twins. However, data in support of such a practice are limited and conflicting. The contradictory results may be related to the fact that in most of these studies, the analysis of the predictive value of serial measurements of cervical length was limited to data derived from only two sequential measurements of cervical length, while data on the predictive value of multiple (>2) measurements are scarce.

OBJECTIVE

We sought to determine whether serial measurements of cervical length can improve the prediction of preterm birth in asymptomatic women with twin gestations compared with a single measurement of cervical length at midgestation.

STUDY DESIGN

This was a retrospective cohort study of women with twin pregnancies followed up in a tertiary medical center from 2012 through 2014. All participants underwent routine measurement of cervical length at midgestation and every 2-3 weeks thereafter until 28-32 weeks. For each patient, cervical length was determined at the following time periods: 18+0 to 21+6 weeks (period 1, routine exam), 22+0 to 24+6 weeks (period 2), 25+0 to 27+6 weeks (period 3), and 28+0 to 32+0 weeks (period 4). Measurements of cervical length at periods 2-4 were analyzed in the form of either absolute length (in millimeters) or percent shortening relative to cervical length at period 1. The performance of a stepwise algorithm that incorporated serial measurements of cervical length for the prediction of preterm birth was compared to that achieved with a single measurement of cervical length at period 1.

RESULTS

Overall, 441 women with twin pregnancies who were eligible for the study underwent a total of 2374 cervical length measurements. The association of a short cervix (<10th percentile) with preterm birth at <32 weeks persisted in each of the 4 periods of gestation [odds ratio (95% confidence interval): 7.2 (3.1-16.5), 15.3 (6.4-36.7), 10.3 (4.4-24.3), and 23.1(8.3-64.1), respectively]. Compared with a single measurement of cervical length at midgestation (period 1), a stepwise algorithm integrating serial cervical length measurements from all 4 successive gestational age periods resulted in a significant increase in the area under the receiver operating characteristic curve (0.917 vs 0.613, P < .001). Similarly, when a target false-positive rate of 5% was used, the same stepwise algorithm was associated with a higher detection rate (69% vs 28%, P < .001), higher positive likelihood ratio (14.54 vs 5.12), and lower negative likelihood ratio (0.32 vs 0.76) for preterm birth at <32 weeks compared with a single measurement of cervical length at period 1.

CONCLUSION

Integration of serial measurements of cervical length using a stepwise algorithm in asymptomatic women with twin gestations can improve the detection of women at risk of preterm birth. Prospective studies are needed to validate these findings, and to investigate whether improved risk assessment performance is sufficient to offset the additional costs associated with serial cervical length measurements.

When Future Change Matters: Modeling Future Price and Diffusion in Health Technology Assessments of Medical Devices

BACKGROUND

Health technology assessments (HTAs) that take account of future price changes have been examined in the literature, but the important issue of price reductions that are generated by the reimbursement decision has been ignored.

OBJECTIVES

To explore the impact of future price reductions caused by increasing uptake on HTAs and decision making for medical devices.

METHODS

We demonstrate the use of a two-stage modeling approach to derive estimates of technology price as a consequence of changes in technology uptake over future periods on the basis of existing theory and supported by empirical studies. We explore the impact on cost-effectiveness and expected value of information analysis in an illustrative example on the basis of a technology in development for preterm birth screening.

RESULTS

The application of our approach to the case study technology generates smaller incremental cost-effectiveness ratios compared with the commonly used single cohort approach. The extent of this reduction in the incremental cost-effectiveness ratio depends on the magnitude of the modeled price reduction, the speed of diffusion, and the length of the assumed technology life horizon. Results of value of information analysis are affected through changes in the expected net benefit calculation, the addition of uncertain parameters, and the diffusion-adjusted estimate of the affected patient population.

CONCLUSIONS

Because modeling future changes in price and uptake has the potential to affect HTA outcomes, modeling techniques that can address such changes should be considered for medical devices that may otherwise be rejected.

A New Look at Care in Pregnancy: Simple, Effective Interventions for Neglected Populations

BACKGROUND

Although this is beginning to change, the content of antenatal care has been relatively neglected in safe-motherhood program efforts. This appears in part to be due to an unwarranted belief that interventions over this period have far less impact than those provided around the time of birth. In this par, we review available evidence for 21 interventions potentially deliverable during pregnancy at high coverage to neglected populations in low income countries, with regard to effectiveness in reducing risk of: maternal mortality, newborn mortality, stillbirth, prematurity and intrauterine growth restriction. Selection was restricted to interventions that can be provided by non-professional health auxiliaries and not requiring laboratory support.

METHODS

In this narrative review, we included relevant Cochrane and other systematic reviews and did comprehensive bibliographic searches. Inclusion criteria varied by intervention; where available randomized controlled trial evidence was insufficient, observational study evidence was considered. For each intervention we focused on overall contribution to our outcomes of interest, across varying epidemiologies.

RESULTS

In the aggregate, achieving high effective coverage for this set of interventions would very substantially reduce risk for our outcomes of interest and reduce outcome inequities. Certain specific interventions, if pushed to high coverage have significant potential impact across many settings. For example, reliable detection of pre-eclampsia followed by timely delivery could prevent up to ¼ of newborn and stillbirth deaths and over 90% of maternal eclampsia/pre-eclampsia deaths. Other interventions have potent effects in specific settings: in areas of high P falciparum burden, systematic use of insecticide-treated nets and/or intermittent presumptive therapy in pregnancy could reduce maternal mortality by up to 10%, newborn mortality by up to 20%, and stillbirths by up to 25-30%. Behavioral interventions targeting practices at birth and in the hours that follow can have substantial impact in settings where many births happen at home: in such circumstances early initiation of breastfeeding can reduce risk of newborn death by up to 20%; good thermal care practices can reduce mortality risk by a similar order of magnitude.

CONCLUSIONS

Simple interventions delivered during pregnancy have considerable potential impact on important mortality outcomes. More programmatic effort is warranted to ensure high effective coverage.

Use of metabolomics for the identification and validation of clinical biomarkers for preterm birth: Preterm SAMBA

Background

Spontaneous preterm birth is a complex syndrome with multiple pathways interactions determining its occurrence, including genetic, immunological, physiologic, biochemical and environmental factors. Despite great worldwide efforts in preterm birth prevention, there are no recent effective therapeutic strategies able to decrease spontaneous preterm birth rates or their consequent neonatal morbidity/mortality. The Preterm SAMBA study will associate metabolomics technologies to identify clinical and metabolite predictors for preterm birth. These innovative and unbiased techniques might be a strategic key to advance spontaneous preterm birth prediction.

Methods/design

Preterm SAMBA study consists of a discovery phase to identify biophysical and untargeted metabolomics from blood and hair samples associated with preterm birth, plus a validation phase to evaluate the performance of the predictive modelling. The first phase, a case–control study, will randomly select 100 women who had a spontaneous preterm birth (before 37 weeks) and 100 women who had term birth in the Cork Ireland and Auckland New Zealand cohorts within the SCOPE study, an international consortium aimed to identify potential metabolomic predictors using biophysical data and blood samples collected at 20 weeks of gestation. The validation phase will recruit 1150 Brazilian pregnant women from five participant centres and will collect blood and hair samples at 20 weeks of gestation to evaluate the performance of the algorithm model (sensitivity, specificity, predictive values and likelihood ratios) in predicting spontaneous preterm birth (before 34 weeks, with a secondary analysis of delivery before 37 weeks).

Discussion

The Preterm SAMBA study intends to step forward on preterm birth prediction using metabolomics techniques, and accurate protocols for sample collection among multi-ethnic populations. The use of metabolomics in medical science research is innovative and promises to provide solutions for disorders with multiple complex underlying determinants such as spontaneous preterm birth.

Screening for post 32-week preterm birth risk: how helpful is routine perinatal data collection?

Background

Preterm birth is a clinical event significant but difficult to predict. Biomarkers such as fetal fibronectin and cervical length are effective, but the often are used only for women with clinically suspected preterm risk. It is unknown whether routinely collected data can be used in early pregnancy to stratify preterm birth risk by identifying asymptomatic women. This paper tries to determine the value of the Victorian Perinatal Data Collection (VPDC) dataset in predicting preterm birth and screening for invasive tests.

Methods

De-identified VPDC report data from 2009 to 2013 were extracted for patients from Barwon Health in Victoria. Logistic regression models with elastic-net regularization were fitted to predict 37-week preterm, with the VPDC antenatal variables as predictors. The models were also extended with two additional variables not routinely noted in the VPDC: previous preterm birth and partner smoking status, testing the hypothesis that these two factors add prediction accuracy. Prediction performance was evaluated using a number of metrics, including Brier scores, Nagelkerke’s R², c statistic.

Results

Although the predictive model utilising VPDC data had a low overall prediction performance, it had a reasonable discrimination (c statistic 0.646 [95% CI: 0.596–0.697] for 37-week preterm) and good calibration (goodness-of-fit p = 0.61). On a decision threshold of 0.2, a Positive Predictive Value (PPV) of 0.333 and a negative predictive value (NPV) of 0.941 were achieved. Data on previous preterm and partner smoking did not significantly improve prediction.

Conclusions

For multiparous women, the routine data contains information comparable to some purposely-collected data for predicting preterm risk. But for nulliparous women, the routine data contains insufficient data related to antenatal complications.

Repeat Measurement of Cervical Length in Women with Threatened Preterm Labor

OBJECTIVE

To examine the value of a repeat measurement some days after the first cervical length measurement done at the time of preterm contractions.

STUDY DESIGN

Retrospective study involving women with singleton pregnancies who presented with preterm contractions at 24 to 33 + 6 weeks of gestation. The cervical length was measured at the time of presentation and some days afterwards.

RESULTS

The study population consisted of 17 cases with a preterm delivery within 14 days and 288 uneventful pregnancies. Univariate logistic regression analysis indicated a significant correlation between delivery within 14 days and both, the first and second cervical length measurements as well as the difference between the two measurements. Up to a false positive rate of 20 %, ROC curve analysis showed an improved detection rate for preterm delivery by inluding both measurements. At a false positive rate of 10 % - which corresponds to a first and second cervical length of 10 and 9 mm - the detection rate was 17.6 % with the first cervical length measurement, 47.0 % with the second and 52.9 % if the difference between both measurements was added.

CONCLUSION

Our results indicate that in women with symptoms of preterm labor it is worth to repeat the measurement some days later and to take into account the difference between both measurements.

Vulnerable pregnant women in antenatal practice: Caregiver's perception of workload, associated burden and agreement with objective caseload, and the influence of a structured organisation of antenatal risk management

INTRODUCTION

pregnancy care for vulnerable women is often perceived as a burden by caregivers as vulnerable clients require complex case management, additional time, and more often show adverse perinatal outcomes. Vulnerable clients bring about additional work strain for the caregiver, especially when the workload is high. We define client vulnerability as coexistence of psychopathology, psychosocial problems or substance use, together with features of deprivation. We investigated, as part of a national programme, whether the subjective caregiver's perception of workload and the objective registry-based caseload of vulnerable clients are in agreement, and whether a structured organisation of antenatal risk management reduces the burden associated with the perceived workload, in particular if the objective caseload is high.

METHODS

we combined three data sources: (1) at the unit level (i.e. midwifery practice, obstetric unit) interview data from caregivers, from which we derived a) the (subjective) caregiver's perception of workload, b) the associated burden and c) organisational structure of antenatal risk management, (2) at the unit level perinatal registry data, from which we derived a) unit characteristics and b) (objective) unit specific caseload, and (3) at the individual client level survey data collected during the first antenatal visit, from which the prevalence of vulnerable clients was derived. The study area was the South-West Netherlands (2.5 million inhabitants), containing areas with varying degrees of urbanisation and deprivation.

FINDINGS

sixteen units had complete data on all measures. Generally, subjective workload and objective caseload were only weakly related, the relation being modified by the organisation of antenatal risk management. If the organisational structure of antenatal risk management was low, the experienced burden was high, even if the objective caseload was low. Highly structured antenatal risk management was associated with a medium to low burden.

DISCUSSION

our observational study suggests that even a high caseload can be dealt with by structured antenatal risk management. A change from the current individual case-finding policies towards a more universal screen-like approach may thus benefit both the client and the caregiver.

A best practice position statement on pregnancy in chronic kidney disease: the Italian Study Group on Kidney and Pregnancy

Pregnancy is increasingly undertaken in patients with chronic kidney disease (CKD) and, conversely, CKD is increasingly diagnosed in pregnancy: up to 3 % of pregnancies are estimated to be complicated by CKD. The heterogeneity of CKD (accounting for stage, hypertension and proteinuria) and the rarity of several kidney diseases make risk assessment difficult and therapeutic strategies are often based upon scattered experiences and small series. In this setting, the aim of this position statement of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology is to review the literature, and discuss the experience in the clinical management of CKD in pregnancy. CKD is associated with an increased risk for adverse pregnancy-related outcomes since its early stage, also in the absence of hypertension and proteinuria, thus supporting the need for a multidisciplinary follow-up in all CKD patients. CKD stage, hypertension and proteinuria are interrelated, but they are also independent risk factors for adverse pregnancy-related outcomes. Among the different kidney diseases, patients with glomerulonephritis and immunologic diseases are at higher risk of developing or increasing proteinuria and hypertension, a picture often difficult to differentiate from preeclampsia. The risk is higher in active immunologic diseases, and in those cases that are detected or flare up during pregnancy. Referral to tertiary care centres for multidisciplinary follow-up and tailored approaches are warranted. The risk of maternal death is, almost exclusively, reported in systemic lupus erythematosus and vasculitis, which share with diabetic nephropathy an increased risk for perinatal death of the babies. Conversely, patients with kidney malformation, autosomal-dominant polycystic kidney disease, stone disease, and previous upper urinary tract infections are at higher risk for urinary tract infections, in turn associated with prematurity. No risk for malformations other than those related to familiar urinary tract malformations is reported in CKD patients, with the possible exception of diabetic nephropathy. Risks of worsening of the renal function are differently reported, but are higher in advanced CKD. Strict follow-up is needed, also to identify the best balance between maternal and foetal risks. The need for further multicentre studies is underlined.

Vaginal progesterone prophylaxis for preterm birth (the OPPTIMUM study): a multicentre, randomised, double-blind trial

BACKGROUND

Progesterone administration has been shown to reduce the risk of preterm birth and neonatal morbidity in women at high risk, but there is uncertainty about longer term effects on the child.

METHODS

We did a double-blind, randomised, placebo-controlled trial of vaginal progesterone, 200 mg daily taken from 22-24 to 34 weeks of gestation, on pregnancy and infant outcomes in women at risk of preterm birth (because of previous spontaneous birth at ≤34 weeks and 0 days of gestation, or a cervical length ≤25 mm, or because of a positive fetal fibronectin test combined with other clinical risk factors for preterm birth [any one of a history in a previous pregnancy of preterm birth, second trimester loss, preterm premature fetal membrane rupture, or a history of a cervical procedure to treat abnormal smears]). The objective of the study was to determine whether vaginal progesterone prophylaxis given to reduce the risk of preterm birth affects neonatal and childhood outcomes. We defined three primary outcomes: fetal death or birth before 34 weeks and 0 days gestation (obstetric), a composite of death, brain injury, or bronchopulmonary dysplasia (neonatal), and a standardised cognitive score at 2 years of age (childhood), imputing values for deaths. Randomisation was done through a web portal, with participants, investigators, and others involved in giving the intervention, assessing outcomes, or analysing data masked to treatment allocation until the end of the study. Analysis was by intention to treat. This trial is registered at ISRCTN.com, number ISRCTN14568373.

FINDINGS

Between Feb 2, 2009, and April 12, 2013, we randomly assigned 1228 women to the placebo group (n=610) and the progesterone group (n=618). In the placebo group, data from 597, 587, and 439 women or babies were available for analysis of obstetric, neonatal, and childhood outcomes, respectively; in the progesterone group the corresponding numbers were 600, 589, and 430. After correction for multiple outcomes, progesterone had no significant effect on the primary obstetric outcome (odds ratio adjusted for multiple comparisons [OR] 0·86, 95% CI 0·61-1·22) or neonatal outcome (OR 0·62, 0·38-1·03), nor on the childhood outcome (cognitive score, progesterone group vs placebo group, 97·3 [SD 17·9] vs 97·7 [17·5]; difference in means -0·48, 95% CI -2·77 to 1·81). Maternal or child serious adverse events were reported in 70 (11%) of 610 patients in the placebo group and 59 (10%) of 616 patients in the progesterone group (p=0·27).

INTERPRETATION

Vaginal progesterone was not associated with reduced risk of preterm birth or composite neonatal adverse outcomes, and had no long-term benefit or harm on outcomes in children at 2 years of age.

FUNDING

Efficacy and Mechanism Evaluation (EME) Programme, a Medical Research Council (MRC) and National Institute for Health Research (NIHR) partnership. The EME Programme is funded by the MRC and NIHR, with contributions from the Chief Scientist Office in Scotland and National Institute for Social Care and Research in Wales.

Transcription Analysis of the Myometrium of Labouring and Non-Labouring Women

An incomplete understanding of the molecular mechanisms that initiate normal human labour at term seriously hampers the development of effective ways to predict, prevent and treat disorders such as preterm labour. Appropriate analysis of large microarray experiments that compare gene expression in non-labouring and labouring gestational tissues is necessary to help bridge these gaps in our knowledge. In this work, gene expression in 48 (22 labouring, 26 non-labouring) lower-segment myometrial samples collected at Caesarean section were analysed using Illumina HT-12 v4.0 BeadChips. Normalised data were compared between labouring and non-labouring groups using traditional statistical methods and a novel network graph approach. We sought technical validation with quantitative real-time PCR, and biological replication through inverse variance-weighted meta-analysis with published microarray data. We have extended the list of genes suggested to be associated with labour: Compared to non-labouring samples, labouring samples showed apparent higher expression at 960 probes (949 genes) and apparent lower expression at 801 probes (789 genes) (absolute fold change ≥1.2, rank product percentage of false positive value (RP-PFP) <0.05). Although half of the women in the labouring group had received pharmaceutical treatment to induce or augment labour, sensitivity analysis suggested that this did not confound our results. In agreement with previous studies, functional analysis suggested that labour was characterised by an increase in the expression of inflammatory genes and network analysis suggested a strong neutrophil signature. Our analysis also suggested that labour is characterised by a decrease in the expression of muscle-specific processes, which has not been explicitly discussed previously. We validated these findings through the first formal meta-analysis of raw data from previous experiments and we hypothesise that this represents a change in the composition of myometrial tissue at labour. Further work will be necessary to reveal whether these results are solely due to leukocyte infiltration into the myometrium as a mechanism initiating labour, or in addition whether they also represent gene changes in the myocytes themselves. We have made all our data available at www.ebi.ac.uk/arrayexpress/ (accession number E-MTAB-3136) to facilitate progression of this work.

Perinatal and Delivery Management of Infants with Congenital Heart Disease

Advances in fetal echocardiography have improved prenatal diagnosis of congenital heart disease (CHD) and allowed better delivery and perinatal management. Some newborns with CHD require urgent intervention after delivery. In these cases, delivery close to a pediatric cardiac center may be considered, and the presence of a specialized cardiac team in the delivery room or urgent transport of the infant should be planned in advance. Delivery planning, monitoring in labor, rapid intervention at birth if needed, and avoidance of iatrogenic preterm delivery have the potential to improve outcomes for infants with prenatally diagnosed CHD.

Stillbirths: economic and psychosocial consequences

Despite the frequency of stillbirths, the subsequent implications are overlooked and underappreciated. We present findings from comprehensive, systematic literature reviews, and new analyses of published and unpublished data, to establish the effect of stillbirth on parents, families, health-care providers, and societies worldwide. Data for direct costs of this event are sparse but suggest that a stillbirth needs more resources than a livebirth, both in the perinatal period and in additional surveillance during subsequent pregnancies. Indirect and intangible costs of stillbirth are extensive and are usually met by families alone. This issue is particularly onerous for those with few resources. Negative effects, particularly on parental mental health, might be moderated by empathic attitudes of care providers and tailored interventions. The value of the baby, as well as the associated costs for parents, families, care providers, communities, and society, should be considered to prevent stillbirths and reduce associated morbidity.

Vaginal progesterone to prevent preterm birth in pregnant women with a sonographic short cervix: clinical and public health implications

Vaginal progesterone administration to women with a sonographic short cervix is an efficacious and safe intervention used to prevent preterm birth and neonatal morbidity and mortality. The clinical and public health implications of this approach in the United States have been critically appraised and compared to other therapeutic interventions in obstetrics. Vaginal progesterone administration to women with a transvaginal sonographic cervical length (CL) ≤25 mm before 25 weeks of gestation is associated with a significant and substantial reduction of the risk for preterm birth from <28 to <35 weeks of gestation, respiratory distress syndrome, composite neonatal morbidity and mortality, admission to the neonatal intensive care unit, and mechanical ventilation. These beneficial effects have been achieved in women with a singleton gestation, with or without a history of spontaneous preterm birth, and did not differ significantly as a function of CL (<10 mm, 10-20 mm, or 21-25 mm). The number of patients required for treatment to prevent 1 case of preterm birth or adverse neonatal outcomes ranges from 10-19 women. The number needed to screen for the prevention of 1 case of preterm birth before 34 weeks of gestation is 125 women, and 225 for the prevention of 1 case of major neonatal morbidity or neonatal mortality. Several cost-effectiveness and decision analyses have shown that the combination of universal transvaginal CL screening and vaginal progesterone administration to women with a short cervix is a cost-effective intervention that prevents preterm birth and associated perinatal morbidity and mortality. Universal assessment of CL and treatment with vaginal progesterone for singleton gestations in the United States would result in an annual reduction of approximately 30,000 preterm births before 34 weeks of gestation and of 17,500 cases of major neonatal morbidity or neonatal mortality. In summary, there is compelling evidence to recommend universal transvaginal CL screening at 18-24 weeks of gestation in women with a singleton gestation and to offer vaginal progesterone to those with a CL ≤25 mm, regardless of the history of spontaneous preterm birth, with the goal of preventing preterm birth and neonatal morbidity and mortality.

Cervical pessary to prevent preterm birth in women with twin gestation and sonographic short cervix: a multicenter randomized controlled trial (PECEP-Twins)

BACKGROUND

Spontaneous preterm birth (SPB) is the leading cause of perinatal morbidity and mortality. In twins, the rate of preterm birth is higher than in singletons; interventions to prevent preterm birth are needed in this high-risk population.

OBJECTIVE

We sought to test whether a cervical pessary reduces the preterm birth rate in twin pregnancies with sonographic short cervix.

STUDY DESIGN

A prospective, open-label, multicenter, randomized clinical trial was conducted in 5 hospitals in Spain. The ethics committees of all participating hospitals approved the protocol. The trial was registered as ClinicalTrials.gov, number NCT01242410. Eligible women were scanned in Spain. The primary outcome was SPB <34 weeks of gestation. Neonatal morbidity and mortality were also evaluated.

RESULTS

Cervical length was measured in 2287 women; 137 pregnant women with a sonographic cervical length ≤25 mm (of 154 detected with a short cervix) were randomly assigned to receive a cervical pessary or expectant management (1:1 ratio). SPB <34 weeks of gestation was significantly less frequent in the pessary group than in the expectant management group (11/68 [16.2%] vs 26/66 [39.4%]; relative risk, 0.41; 95% confidence interval, 0.22-0.76). Pessary use was associated with a significant reduction in the rate of birthweight <2500 g (P = .01). No significant differences were observed in composite neonatal morbidity outcome (8/136 [5.9%] vs 12/130 [9.1%]; relative risk, 0.64; 95% confidence interval, 0.27-1.50) or neonatal mortality (none) between the groups. No serious adverse effects associated with the use of a cervical pessary were observed.

CONCLUSION

The insertion of a cervical pessary was associated with a significant reduction in the SPB rate. We propose the use of a cervical pessary for preventing preterm birth in twin pregnancies of mothers with a short cervix.

Identifying metabolite markers for preterm birth in cervicovaginal fluid by magnetic resonance spectroscopy

INTRODUCTION

Preterm birth (PTB) may be preceded by changes in the vaginal microflora and metabolite profiles.

OBJECTIVES

We sought to characterise the metabolite profile of cervicovaginal fluid (CVF) of pregnant women by 1H NMR spectroscopy, and assess their predictive value for PTB.

METHODS

A pair of high-vaginal swabs was obtained from pregnant women with no evidence of clinical infection and grouped as follows: asymptomatic low risk (ALR) women with no previous history of PTB, assessed at 20-22 gestational weeks, g.w., n = 83; asymptomatic high risk (AHR) women with a previous history of PTB, assessed at both 20-22 g.w., n = 71, and 26-28 g.w., n = 58; and women presenting with symptoms of preterm labor (PTL) (SYM), assessed at 24-36 g.w., n = 65. Vaginal secretions were dissolved in phosphate buffered saline and scanned with a 9.4 T NMR spectrometer.

RESULTS

Six metabolites (lactate, alanine, acetate, glutamine/glutamate, succinate and glucose) were analysed. In all study cohorts vaginal pH correlated with lactate integral (r = -0.62, p < 0.0001). Lactate integrals were higher in the term ALR compared to the AHR (20-22 g.w.) women (p = 0.003). Acetate integrals were higher in the preterm versus term women for the AHR (20-22 g.w.) (p = 0.048) and SYM (p = 0.003) groups; and was predictive of PTB < 37 g.w. (AUC 0.78; 95 % CI 0.61-0.95), and delivery within 2 weeks of the index assessment (AUC 0.84; 95 % CI 0.64-1) in the SYM women, whilst other metabolites were not.

CONCLUSION

High CVF acetate integral of women with symptoms of PTL appears predictive of preterm delivery, as well as delivery within 2 weeks of presentation.

Cervical phosphorylated insulin-like growth factor binding protein-1 test for the prediction of preterm birth: a systematic review and metaanalysis

OBJECTIVE

To assess the accuracy of the cervical phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1) test to predict preterm birth in women with and without symptoms of preterm labor through the use of formal methods for systematic reviews and metaanalytic techniques.

DATA SOURCES

PubMed, Embase, Cinahl, Lilacs, and Medion (all from inception to June 30, 2015), reference lists, conference proceedings, and Google scholar.

STUDY ELIGIBILITY CRITERIA

Cohort or cross-sectional studies that reported on the predictive accuracy of the cervical phIGFBP-1 test for preterm birth.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two reviewers independently selected studies, assessed the risk of bias, and extracted the data. Summary receiver-operating characteristic curves, pooled sensitivities and specificities, and summary likelihood ratios were generated.

RESULTS

Forty-three studies met the inclusion criteria, of which 15 provided data on asymptomatic women (n = 6583) and 34 on women with an episode of preterm labor (n = 3620). Among asymptomatic women, the predictive accuracy of the cervical phIGFBP-1 test for preterm birth at <37, <34, and <32 weeks of gestation was minimal, with pooled sensitivities and specificities and summary positive and negative likelihood ratios ranging from 14% to 47%, 76% to 93%, 1.5 to 4.4, and 0.6 to 1.0, respectively. Among women with an episode of preterm labor, the test had a low predictive performance for delivery within 7 and 14 days of testing, and preterm birth at <34 and <37 weeks of gestation with pooled sensitivities and specificities and summary positive and negative likelihood ratios that varied between 60% and 68%, 77% and 81%, 2.7 and 3.5, and 0.4 and 0.5, respectively. A negative test result in women with an episode of preterm labor had a low to moderate accuracy to identify women who are not at risk for delivering within the next 48 hours (summary negative likelihood ratio of 0.28 in all women and 0.23 in women with singleton gestations).

CONCLUSION

Cervical phIGFBP-1 has the potential utility to identify patients with an episode of preterm labor who will not deliver within 48 hours. However, its overall predictive ability for the identification of symptomatic and asymptomatic women at risk for preterm birth is limited.

Predictive accuracy of changes in transvaginal sonographic cervical length over time for preterm birth: a systematic review and metaanalysis

OBJECTIVE

To determine the accuracy of changes in transvaginal sonographic cervical length over time in predicting preterm birth in women with singleton and twin gestations.

DATA SOURCES

PubMed, Embase, Cinahl, Lilacs, and Medion (all from inception to June 30, 2015), bibliographies, Google scholar, and conference proceedings. Cohort or cross-sectional studies reporting on the predictive accuracy for preterm birth of changes in cervical length over time.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two reviewers independently selected studies, assessed the risk of bias, and extracted the data. Summary receiver-operating characteristic curves, pooled sensitivities and specificities, and summary likelihood ratios were generated.

RESULTS

Fourteen studies met the inclusion criteria, of which 7 provided data on singleton gestations (3374 women) and 8 on twin gestations (1024 women). Among women with singleton gestations, the shortening of cervical length over time had a low predictive accuracy for preterm birth at <37 and <35 weeks of gestation with pooled sensitivities and specificities, and summary positive and negative likelihood ratios ranging from 49% to 74%, 44% to 85%, 1.3 to 4.1, and 0.3 to 0.7, respectively. In women with twin gestations, the shortening of cervical length over time had a low to moderate predictive accuracy for preterm birth at <34, <32, <30, and <28 weeks of gestation with pooled sensitivities and specificities, and summary positive and negative likelihood ratios ranging from 47% to 73%, 84% to 89%, 3.8 to 5.3, and 0.3 to 0.6, respectively. There were no statistically significant differences between the predictive accuracies for preterm birth of cervical length shortening over time and the single initial and/or final cervical length measurement in 8 of 11 studies that provided data for making these comparisons. In the largest and highest-quality study, a single measurement of cervical length obtained at 24 or 28 weeks of gestation was significantly more predictive of preterm birth than any decrease in cervical length between these gestational ages.

CONCLUSIONS

Change in transvaginal sonographic cervical length over time is not a clinically useful test to predict preterm birth in women with singleton or twin gestations. A single cervical length measurement obtained between 18 and 24 weeks of gestation appears to be a better test to predict preterm birth than changes in cervical length over time.

Abnormal Middle Cerebral Artery Doppler Associates with Spontaneous Preterm Birth in Normally Grown Fetuses

OBJECTIVE

Our aim was to evaluate whether Doppler changes in the fetal middle cerebral (MCA) and umbilical arteries (UA) suggesting fetal hypoxemia precede the onset of spontaneous preterm birth (PTB).

METHODS

We studied 2,340 appropriate-for-gestational-age singleton pregnancies that had MCA and UA pulsatility indices (PI) recorded at 28-32 weeks. Values including the cerebroplacental ratio (CPR) were converted into multiples of the median and evaluated according to both gestational age at the onset of labor and the interval between ultrasound and labor. ROC analysis was used to calculate the ability in the prediction of spontaneous PTB before 32, 34 and 37 weeks' gestation.

RESULTS

While no correlations were observed for the UA PI and CPR, lower MCA PI values were associated with an earlier onset of labor (p < 0.001) and a shorter ultrasound-labor interval (p = 0.028). The ROC analysis at different gestational ages and intervals to labor indicated that MCA PI values were poorly predictive of spontaneous PTB (all areas under the curve <0.7).

CONCLUSIONS

Low MCA PI values at 28-32 weeks are associated with subsequent spontaneous PTB, indicating that fetal hypoxemia unrelated with placental disease might be implicated in the onset of labor. This association, however, is unlikely to be useful in the prediction of PTB.

Assessment of the Cervix in Pregnant Women Using Shear Wave Elastography: A Feasibility Study

The quantitative assessment of the cervix is crucial for the estimation of pre-term delivery risk and the prediction of the success of labor induction. We conducted a cross-sectional study using shear wave elastography based on the supersonic shear imaging technique. The shear wave speed (SWS) of the lower anterior part of the cervix was quantified over an 8-mm region of interest in 157 pregnant women. Cervical SWS is slightly but significantly reduced in patients diagnosed with pre-term labor and in patients who actually delivered pre-term.

Risk-scoring systems for predicting preterm birth with the aim of reducing associated adverse outcomes

BACKGROUND

Identification of pregnancies that are higher risk than average is important to allow the possibility of interventions aimed at preventing adverse outcomes like preterm birth. Many scoring systems designed to classify the risk of a number of poor pregnancy outcomes (e.g. perinatal mortality, low birthweight, and preterm birth) have been developed, but they have usually been introduced without evaluation of their utility and validity.

OBJECTIVES

To determine whether the use of a risk-screening tool designed to predict preterm birth (in combination with appropriate consequent interventions) reduces the incidence of preterm birth and very preterm birth, and associated adverse outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 June 2015).

SELECTION CRITERIA

All randomised or quasi-randomised (including cluster-randomised) or controlled clinical trials that compared the incidence of preterm birth between groups that used a risk-scoring instrument to predict preterm birth with those who used an alternative instrument, or no instrument; or that compared the use of the same instrument at different gestations. The reports may have been published in peer reviewed or non-peer reviewed publications, or not published, and written in any language.

DATA COLLECTION AND ANALYSIS

All review authors planned to independently assess for inclusion all the potential studies we identified as a result of the search strategy. However, we did not identify any eligible studies.

MAIN RESULTS

Searching revealed no trials of the use of risk-scoring systems for preventing preterm birth.

AUTHORS' CONCLUSIONS

The role of risk-scoring systems in the prevention of preterm birth is unknown.There is a need for prospective studies that evaluate the use of a risk-screening tool designed to predict preterm birth (in combination with appropriate consequent interventions) to prevent preterm birth, including qualitative and/or quantitative evaluation of their impact on women's well-being. If these prove promising, they should be followed by an adequately powered, well-designed randomised controlled trial.

The Relationship Between Maternal Periodontal Status of and Preterm and Low Birth Weight Infants in Iran: A Case Control Study

Aim and Background:

It has been suggested that periodontitis is associated with systemic alterations such as adverse pregnancy outcomes. However, some conflicting results have been reported. This study was conducted to determine the association between periodontitis and preterm birth (PTB), low birth weight (LBW) to obtain information which is necessary for the planning of preventive programs of periodontal disease for pregnant women in this area.

Materials & Methods:

This case-control study was performed on 264 mothers. The index used to determine oral hygiene and periodontal diseases is Community Periodontal Index Treatment Needs (CPITN).

Results:

The mothers in the sample group with single delivery delivered 8 times low birth weight infants more than the mothers in the control group with single delivery. And also the mothers in the sample group with multiple deliveries; delivered 10 times low birth weight infants and 8 times premature infant more than the mothers in the control group.

Conclusion:

More studies should be carried out in through preventing and treating periodontal diseases, expenses incurred due to preterm labor and low birth weight decrease and the society will witness fewer mental problems suffered by such children as they grow up. So we can emphasize the importance of periodontal care in prenatal health programs. And we may suggest that a special program of periodontal disease prevention for pregnant women is very necessary.

The role of placental alpha microglobulin-1 amnisure in determining the status of the fetal membranes; its association with preterm birth. Traditions … traditions …

The integrity of the fetal amnion-chorion is an imperative for the preservation of a normal pregnancy in the human. The diagnosis of the status of the fetal membranes has traditionally been reduced to either intact or ruptured. In the last decades, evidence has accumulated demonstrating that this clinical approach may well be an over simplification. Practically, all maternal organs experienced physiologic or eventually pathologic changes during the length of the gestational period. We propose that the fetal membranes are also significantly impacted by those changes. The accurate, specific, simplified and low-cost diagnosis of the status of the fetal membranes is of critical importance for the assessment of risk to the pregnancy followed by efficient and prompt treatment. The presence of placental alpha macroglobulin-1 in the vagina specifically indicates a disruption in the integrity of the fetal membranes and may indirectly mean increased risk for preterm birth. Further research to properly characterize this marker and its importance in the care of pregnant woman at risk for preterm birth is strongly recommended.

Antibiotics for asymptomatic bacteriuria in pregnancy

BACKGROUND

Asymptomatic bacteriuria occurs in 2% to 10% of pregnancies and, if not treated, up to 30% of mothers will develop acute pyelonephritis. Asymptomatic bacteriuria has been associated with low birthweight and preterm birth.

OBJECTIVES

To assess the effect of antibiotic treatment for asymptomatic bacteriuria on the development of pyelonephritis and the risk of low birthweight and preterm birth.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (19 March 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomized trials comparing antibiotic treatment with placebo or no treatment in pregnant women with asymptomatic bacteriuria found on antenatal screening.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.

MAIN RESULTS

Fourteen studies, involving almost 2000 women, were included. Antibiotic treatment compared with placebo or no treatment reduced the incidence of pyelonephritis (average risk ratio (RR) 0.23, 95% confidence interval (CI) 0.13 to 0.41; 11 studies, 1932 women; very low quality evidence). Antibiotic treatment was also associated with a reduction in the incidence of low birthweight babies (average RR 0.64, 95% CI 0.45 to 0.93; six studies, 1437 babies; low quality evidence) and preterm birth (RR 0.27, 95% CI 0.11 to 0.62; two studies, 242 women; low quality evidence). A reduction in persistent bacteriuria at the time of delivery was seen (average RR 0.30, 95% CI 0.18 to 0.53; four studies; 596 women). There were very limited data on which to estimate the effect of antibiotics on other infant outcomes and maternal adverse effects were rarely described.Overall, all 14 studies were assessed as being at high or unclear risk of bias. While many studies lacked an adequate description of methods and the risk of bias could only be assessed as unclear, in almost all studies there was at least one domain where the risk of bias was judged as high. The three primary outcomes were assessed with GRADE software and given a quality rating. Evidence for pyelonephritis, preterm birth and birthweight less than 2500 g was assessed as of low or very low quality.

AUTHORS' CONCLUSIONS

While antibiotic treatment is effective in reducing the risk of pyelonephritis in pregnancy, the estimate of the effect is very uncertain because of the very low quality of the evidence. The reduction in low birthweight and preterm birth with antibiotic treatment is consistent with theories about the role of infection in adverse pregnancy outcomes, but this association should be interpreted with caution given the very poor quality of the included studies.

A description of the methods of the Nulliparous Pregnancy Outcomes Study: monitoring mothers-to-be (nuMoM2b)

OBJECTIVE

The primary aim of the "Nulliparous Pregnancy Outcomes Study: monitoring mothers-to-be" is to determine maternal characteristics, which include genetic, physiologic response to pregnancy, and environmental factors that predict adverse pregnancy outcomes.

STUDY DESIGN

Nulliparous women in the first trimester of pregnancy were recruited into an observational cohort study. Participants were seen at 3 study visits during pregnancy and again at delivery. We collected data from in-clinic interviews, take-home surveys, clinical measurements, ultrasound studies, and chart abstractions. Maternal biospecimens (serum, plasma, urine, cervicovaginal fluid) at antepartum study visits and delivery specimens (placenta, umbilical cord, cord blood) were collected, processed, and stored. The primary outcome of the study was defined as pregnancy ending at <37+0 weeks' gestation. Key study hypotheses involve adverse pregnancy outcomes of spontaneous preterm birth, preeclampsia, and fetal growth restriction.

RESULTS

We recruited 10,037 women to the study. Basic characteristics of the cohort at screening are reported.

CONCLUSION

The "Nulliparous Pregnancy Outcomes Study: monitoring mothers-to-be" cohort study methods and procedures can help investigators when they plan future projects.

Relationship between periodontal diseases and preterm birth: Recent epidemiological and biological data

Preterm infants are born prior to completion of 37 weeks of gestation. These patients are seen on the rise despite the efforts put in to control them. Global incidence of preterm birth is around 9.6% of all birth representing 12.9 million births with regional disparities: From 12% to 13% in USA, from 5% to 9% in Europe, and 18% in Africa. First reported by Offenbacher et al. in 1996 relationship exist between maternal periodontal disease and delivery of a preterm infant. This article reviews the recent epidemiological and biological data. The articles were searched on Google, PubMed recent articles were selected. Mainly, three hypotheses by which periodontal bacteria can affect the outcome of pregnancy. Biological hypothesis: (a) Bacterial spreading, (b) Inflammatory products dissemination, (c) Role of fetomaternal immune response against oral pathogens. The promotion of the early detection and treatments of periodontal disease in young women before and during pregnancy will be beneficial especially for women at risk.

Precocious cervical ripening as a screening target to predict spontaneous preterm delivery among asymptomatic singleton pregnancies: a systematic review

Routine second-trimester transvaginal ultrasonographic (TVU) screening for short cervical length (CL) predicts spontaneous preterm delivery (SPTD), albeit with limited sensitivity (35-40%) and a moderate positive likelihood ratio of 4-6. However, CL describes one of the multidimensional changes that are associated with precocious cervical ripening (PCCR) and that also include cervical softening, cervical funneling (CF), and dilation. PCCR, a precursor and a strong predictor for SPTD, was proposed as a potential screening target. We hypothesized that screening for composite measures of PCCR (eg, CL, CF, cervical consistency, and dilation) with the use of either digital examination or TVU would improve the prediction of SPTD compared with screening for short CL alone. We searched PubMed and EMBASE electronic databases for observational cohort studies to evaluate cervical screening in asymptomatic obstetric populations. Multidimensional composite cervical measures were assessed in 10 datasets (n = 22,050 pregnancies) and 12 publications. Appreciable heterogeneity in cervical measurements, data quality, and outcomes across studies prevented quantitative metaanalysis. Only one study reported intra- and interobserver reliability of cervical measurements. The prevalence of CF ranged from 0.7-9.1%. Five studies compared composite measures of PCCR (ie, CL and CF) with short CL alone and consistently reported improved screening performance. Among 3 TVU studies, gains in sensitivity ranged from 5-27%, and increases in positive likelihood ratio ranged from 3-16. Our findings suggest that composite measures of PCCR might serve as valuable screening targets. High-quality interdisciplinary studies that integrate epidemiologic approaches are needed to test this hypothesis and to accelerate the translation of advances in cervical pathophysiology into effective preventive interventions.

Comparison of Perinatal Outcome of Preterm Births Starting in Primary Care versus Secondary Care in Netherlands: A Retrospective Analysis of Nationwide Collected Data

Introduction. In Netherlands, the obstetric care system is divided into primary and secondary care by risk level of the pregnancy. We assessed the incidence of preterm birth according to level of care and the association between level of care at time of labor onset and delivery and adverse perinatal outcome. Methods. Singleton pregnancies recorded in Netherlands Perinatal Registry between 1999 and 2007, with spontaneous birth between 25(+0) and 36(+6) weeks, were included. Three groups were compared: (1) labor onset and delivery in primary care; (2) labor onset in primary care and delivery in secondary care; (3) labor onset and delivery in secondary care. Multivariable logistic regression analyses were performed to calculate the risk of perinatal mortality and Apgar score ≤4. Results. Of all preterm deliveries, 42% had labor onset and 7.9% had also delivery in primary care. Women with labor onset between 34(+0) and 36(+6) weeks who were referred before delivery to secondary care had the lowest risk of perinatal mortality (aOR 0.49 (0.30-0.79)). Risk of perinatal mortality (aOR 1.65; 95% CI 1.20-2.27) and low Apgar score (aOR 1.95; 95% CI 1.53-2.48) were significantly increased in preterm home delivery. Conclusion. Referral before delivery is associated with improved perinatal outcome in the occurrence of preterm labor onset in primary care.

Home uterine monitoring for detecting preterm labour

BACKGROUND

To reduce the morbidity and mortality associated with preterm birth, home uterine activity monitoring aims for early detection of increased contraction frequency, and early intervention with tocolytic drugs to inhibit labour and prolong pregnancy. However, the effectiveness of such monitoring is disputed.

OBJECTIVES

To determine whether home uterine activity monitoring is effective in improving the outcomes for women and their infants considered to be at high risk of preterm birth, when compared with conventional or other care packages that do not include home uterine monitoring.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 October 2014), CENTRAL (The Cochrane Library 2014, Issue 8), MEDLINE (1966 to 31 August 2014), EMBASE (1974 to 31 August 2014), CINAHL (1982 to 31 August 2014) and scanned reference lists of retrieved studies.

SELECTION CRITERIA

Randomised control trials of home uterine activity monitoring, with or without patient education programmes, for women at risk for preterm birth, in comparison to the same care package without home uterine activity monitoring.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We did not attempt to contact authors to resolve queries.

MAIN RESULTS

There were 15 included studies (total number of enrolled participants 6008); 13 studies contributed data. Women using home uterine monitoring were less likely to experience preterm birth at less than 34 weeks (risk ratio (RR) 0.78; 95% confidence interval (CI) 0.62 to 0.99; three studies, n = 1596; fixed-effect analysis) (GRADE high). The significant difference was not evident when we carried out a sensitivity analysis, restricting the analysis to studies at low risk of bias based on study quality (RR 0.75; 95% CI 0.57 to 1.00, one study, 1292 women). There was no significant difference in the rate of perinatal mortality (RR 1.22; 95% CI 0.86 to 1.72; two studies, n = 2589) (GRADE low)There was no significant difference in the number of preterm births at less than 37 weeks (average RR 0.85; CI 0.72 to 1.01; eight studies, n = 4834; random-effects, T² = 0.03, I² = 68%) (GRADE very low). Infants born to women using home uterine monitoring were less likely to be admitted to neonatal intensive care unit (average RR 0.77; 95% CI 0.62 to 0.96; five studies, n = 2367; random-effects, T² = 0.02, I² = 32%) (GRADE moderate). The difference was not statistically significant when only high quality studies were included (RR 0.86; 95% CI 0.74 to 1.01; one study, n = 1292). Women using home uterine monitoring made more unscheduled antenatal visits (mean difference (MD) 0.49; 95% CI 0.39 to 0.62; two studies, n = 3707) (GRADE moderate). Women using home uterine monitoring were also more likely to have prophylactic tocolytic drug therapy (average RR 1.21; 95% CI 1.01 to 1.45; seven studies, n = 4316; random-effects. T² = 0.03, I² = 62%) but this difference was no longer significant when the analysis was restricted to higher quality studies (average RR 1.22; 95% CI 0.90 to 1.65, three studies, n = 3749,random-effects, T² = 0.05, I² = 76%) (GRADE low). One small study reported that the home uterine monitoring group spent fewer days in hospital antenatally. No data on maternal anxiety or acceptability were found.

AUTHORS' CONCLUSIONS

Home uterine monitoring may result in fewer admissions to a neonatal intensive care unit but more unscheduled antenatal visits and tocolytic treatment, but the level of evidence is generally low to moderate. Important group differences were not evident when sensitivity analysis was undertaken using only high quality trials. There is no impact on maternal and perinatal outcomes such as perinatal mortality or incidence of preterm birth.

Use of amniotic fluid for determining pregnancies at risk of preterm birth and for studying diseases of potential environmental etiology

Amniotic fluid (AF) is a biological medium uniquely suited for the study of early exposure of the human fetus to environmental contaminants acquired by the mother before and during pregnancy. Traditional diagnostic applications of AF have focused almost exclusively on the diagnosis of genetic aberrations such as Trisomy-21 and on heritable diseases in high-risk pregnancies. Since more than 50 anthropogenic compounds have been detected in AF, there is considerable potential in utilizing fetal protein biomarkers as indicators of health effects related to prenatal toxic exposure. Here, we focus on preterm birth (PTB) to illustrate opportunities and limitations of using AF as a diagnostic matrix. Representing a pervasive public health challenge worldwide, PTB cannot be managed simply by improving hygiene and broadening access to healthcare. This is illustrated by 15-year increases of PTB in the U.S. from 1989 to 2004. AF is uniquely suited as a matrix for early detection of the association between fetal exposures and PTB due to its fetal origin and the fact that it is sampled from women who are at higher risk of PTB. This critical review shows the occurrence in AF of a number of xenobiotics, including endocrine-disrupting compounds (EDCs), which are known or may reasonably be expected to shorten fetal gestation. It is not yet known whether EDCs, including bisphenol A, phytoestrogens, and polychlorinated biphenyls (PCBs), can affect the expression of proteins considered viable or potential biomarkers for the onset of PTB. As such, the diagnostic value of AF is broad and has not yet been fully explored for prenatal diagnosis of pregnancies at risk from toxic, environmental exposures and for the elucidation of mechanisms underlying important public health challenges including PTB.

Early prediction of spontaneous twin very preterm birth: a population based study 2002-2012

OBJECTIVE

The aim of this study was to establish early pregnancy risk indicators for spontaneous twin very preterm birth.

METHODS

We conducted a retrospective observational population-based study. Twenty-one potential early pregnancy risk factors were analyzed using multivariable logistic regression to determine which of them was independently associated with spontaneous twin very preterm birth.

RESULTS

Of 1815 spontaneous twin births 15.3% (277) occurred before 32 weeks. Previous preterm delivery (aOR 3.73; 95% CI, 2.52-5.52), nulliparity (aOR 2.94; 95% CI, 2.09-4.14), body mass index <18.5 (aOR 1.86; 95% CI, 1.12-3.10), body mass index ≥30 (aOR 1.87; 95% CI, 1.21-2.89), hysteroscopic metroplasty (aOR 1.63; 1.07-2.49), conization (aOR 2.05; 95% CI, 1.07-3.94) and monochorionicity (aOR 1.83; 95% CI, 1.28-2.63) were significantly associated with twin very preterm birth.

CONCLUSIONS

Pending verification in other populations, twin pregnancies at significant risk for spontaneous very preterm birth can be identified in early pregnancy using several risk indicators.

The use of maternal C-reactive protein in the predicting of preterm labor and tocolytic therapy in preterm labor women

Background:

Levels of a number of some biomarkers have been associated with spontaneous preterm birth. This study was aimed to evaluate the relation between C-reactive protein (CRP) with preterm labor and response to tocolytic therapy.

Materials and Methods:

Seventy five pregnant women with symptoms of preterm labor (cases) in compare with 75 term women (controls) were enrolled. Baseline data and CRP was recorded. So, cases were under treatment tocolysis with the use of magnesium sulfate, and then they were followed till delivery time to assess the response to the treatment.

Results:

Sixteen patients with symptoms of preterm labor did not response to the treatment and delivered prematurely and 59 women response to tocolytic treatment and delivered at term. The curve constructed cut-off value for >3.6 (AUC, 0.683; SE, 0.041; P < 0.0001) for CRP, indicating a significant relationship with preterm labor. Also, there was significant relationship between CRP level with response to the treatment in cut-off >1.8 (AUC, 0.738; SE, 0.076; P = 0.001) for CRP.

Conclusions:

Maternal concentrations of CRP can be used as appropriate biomarker for predicting preterm labor and response to tocolytic therapy in pregnant women.

Multivariate adaptive regression splines analysis to predict biomarkers of spontaneous preterm birth

OBJECTIVE

To develop classification models of demographic/clinical factors and biomarker data from spontaneous preterm birth in African Americans and Caucasians.

DESIGN

Secondary analysis of biomarker data using multivariate adaptive regression splines (MARS), a supervised machine learning algorithm method.

SETTING

Analysis of data on 36 biomarkers from 191 women was reduced by MARS to develop predictive models for preterm birth in African Americans and Caucasians.

SAMPLES

Maternal plasma, cord plasma collected at admission for preterm or term labor and amniotic fluid at delivery.

METHODS

Data were partitioned into training and testing sets. Variable importance, a relative indicator (0-100%) and area under the receiver operating characteristic curve (AUC) characterized results.

RESULTS

Multivariate adaptive regression splines generated models for combined and racially stratified biomarker data. Clinical and demographic data did not contribute to the model. Racial stratification of data produced distinct models in all three compartments. In African Americans maternal plasma samples IL-1RA, TNF-α, angiopoietin 2, TNFRI, IL-5, MIP1α, IL-1β and TGF-α modeled preterm birth (AUC train: 0.98, AUC test: 0.86). In Caucasians TNFR1, ICAM-1 and IL-1RA contributed to the model (AUC train: 0.84, AUC test: 0.68). African Americans cord plasma samples produced IL-12P70, IL-8 (AUC train: 0.82, AUC test: 0.66). Cord plasma in Caucasians modeled IGFII, PDGFBB, TGF-β1 , IL-12P70, and TIMP1 (AUC train: 0.99, AUC test: 0.82). Amniotic fluid in African Americans modeled FasL, TNFRII, RANTES, KGF, IGFI (AUC train: 0.95, AUC test: 0.89) and in Caucasians, TNF-α, MCP3, TGF-β3 , TNFR1 and angiopoietin 2 (AUC train: 0.94 AUC test: 0.79).

CONCLUSIONS

Multivariate adaptive regression splines models multiple biomarkers associated with preterm birth and demonstrated racial disparity.

Endocervical and high vaginal quantitative fetal fibronectin in predicting preterm birth

OBJECTIVE

Accurate prediction of spontaneous preterm birth (sPTB) is essential to target interventions. Fetal fibronectin (fFN) is a leading predictor. A quantitative fFN (qfFN) test has improved prediction, based on high vaginal swabs (HVS). It is not known how endocervical (ECS) fFN levels compare, or which has the best predictive value. Our principal aim was to determine the difference in fFN concentration between HVS and ECS and compare their ability to predict sPTB.

METHODS

Asymptomatic high risk women (18(+0)-30(+0) weeks gestation) had secretions sampled from the endocervix (ECS) and vaginal fornix (HVS), analyzed by the quantitative fFN analyzer (Hologic). Mean concentrations were compared; ROC curves were calculated using area under the curve (AUC) for prediction of delivery <30 and 37 weeks.

RESULTS

Mean HVS value was lower than ECS (80 ng/ml (SD142) versus 217 (SD 212) (p < 0.05). Predictive ability was similar: AUC of 0.92 and 0.94, respectively, for prediction of sPTB < 37 and 0.84 and 0.82 for <30 weeks.

CONCLUSIONS

Endocervical qfFN is higher than HVS and clinicians should avoid ECS if using traditional thresholds. ECS and HVS are both useful predictors, but require different threshold values. Further work is needed to determine whether ECS is a better and safe test to justify the difficulty in sampling.

A structured review and exploration of the healthcare costs associated with stillbirth and a subsequent pregnancy in England and Wales

Background

In contrast to other pregnancy complications the economic impact of stillbirth is poorly understood. We aimed to carry out a preliminary exploration of the healthcare costs of stillbirth from the time of pregnancy loss and the period afterwards; also to explore and include the impact of a previous stillbirth on the healthcare costs of the next pregnancy.

Methods

A structured review of the literature including cost studies and description of costs to health-care providers for care provided at the time of stillbirth and in a subsequent pregnancy. Costs in a subsequent pregnancy were compared in three alternative models of care for multiparous women developed from national guidelines and expert opinion: i) “low risk” women who had a live birth, ii) “high risk” women who had a live birth and iii) women with a previous stillbirth.

Results

The costs to the National Health Service (NHS) for investigation immediately following stillbirth ranged from £1,242 (core recommended investigations) to £1,804 (comprehensive investigation). The costs in the next pregnancy following a stillbirth ranged from £2,147 (low-risk woman with a previous healthy child) to £3,751 (Woman with a previous stillbirth of unknown cause). The cost in the next pregnancy following a stillbirth due to a known recurrent or an unknown cause is almost £500 greater than the pregnancy following a stillbirth due to a known non-recurrent cause.

Conclusions

The study has highlighted the paucity of evidence regarding economic issues surrounding stillbirth. Women who have experienced a previous stillbirth are likely to utilise more health care services in their next pregnancy particularly where no cause is found. Every effort should be made to determine the cause of stillbirth to reduce the overall cost to the NHS. The cost associated with identifying the cause of stillbirth could offset the costs of care in the next pregnancy. Future research should concentrate on robust studies looking into the wider economic impact of stillbirth.

The effect of omega-3 polyunsaturated fatty acids on the inflammatory response of the amnion

OBJECTIVE

To investigate the effect of omega-3 PUFAs, eicosapentanoic acid (EPA) and docosohexanoic acid (DHA) on inflammatory cytokine production in the amnion.

STUDY DESIGN

Amnion explants were obtained at elective caesarean sections and cultured in vitro with EPA and DHA. IL-8 and IL-6 secretion was determined by ELISA, the role of PPARγ was investigated using specific agonists and antagonists and activity of MMP assessed by gelatin zymography.

RESULTS

A combination of EPA and DHA significantly reduced the concentration of IL-8 and IL-6 released into the supernatant compared to untreated controls (p<0.001). Stimulation of PPARγ with troglitazone reduced IL-8 production, and the PPARγ antagonist GW9662 partially reversed this effect. The activity of MMP-9 was also significantly reduced by treatment with EPA and DHA in combination compared to untreated control (p<0.05).

CONCLUSION

The omega-3 PUFAs EPA and DHA decrease the inflammatory response of the amnion, and this may be partially mediated through PPARγ.

The human fetus preferentially secretes corticosterone, rather than cortisol, in response to intra-partum stressors

Context

Fetal stress is relevant to newborn outcomes. Corticosterone is rarely quantified in human clinical endocrinology and is found at much lower concentrations than cortisol. However, fetal corticosterone is a candidate hormone as a fetal stress signal.

Objective

Test the hypothesis that preferential fetal corticosterone synthesis occurs in response to fetal intra-partum stress.

Design

Cross-sectional comparison of paired serum corticosteroid concentrations in umbilical artery and vein from 300 women providing consent at admission to a General Hospital Labor and Delivery unit. Pre-term and multiple births were excluded, leaving 265 healthy deliveries.

Main Outcome Measures

Corticosterone and cortisol concentrations determined by LC-MS/MS for umbilical cord venous (V) and arterial (A) samples and used to calculate fetal synthesis (A−V) and proportional fetal synthesis ([A−V]/V). Chart-derived criteria stratified samples by type of delivery, maternal regional analgesia, augmentation of contractions, and clinical rationale for emergent Caesarian delivery.

Results

Cortisol concentrations were higher than corticosterone concentrations; however, the fetus preferentially secretes corticosterone (148% vs 49% proportional increase for cortisol) and differentially secretes corticosterone as fetal stress increases. Fetal corticosterone synthesis is elevated after passage through the birth canal relative to Caesarian deliveries. For vaginal deliveries, augmentation of contractions does not affect corticosteroid concentrations whereas maternal regional analgesia decreases venous (maternal) concentrations and increases fetal synthesis. Fetal corticosterone synthesis is also elevated after C-section indicated by cephalopelvic disproportion after labor, whereas cortisol is not.

Conclusions

The full-term fetus preferentially secretes corticosterone in response to fetal stress during delivery. Fetal corticosterone could serve as a biomarker of fetal stress.