A randomised controlled trial comparing standard or intensive management of reduced fetal movements after 36 weeks gestation--a feasibility study

Effect of encouraging awareness of reduced fetal movement and subsequent clinical management on pregnancy outcome: a systematic review and meta-analysis

OBJECTIVE

Reduced fetal movement, defined as a decrease in the frequency or strength of fetal movements as perceived by the mother, is a common reason for presentation to maternity care. Observational studies have demonstrated an association between reduced fetal movement and stillbirth and fetal growth restriction related to placental insufficiency. However, individual intervention studies have described varying results. This systematic review and meta-analysis aimed to determine whether interventions aimed at encouraging awareness of reduced fetal movement and/or improving its subsequent clinical management reduce the frequency of stillbirth or other important secondary outcomes.

DATA SOURCES

Searches were conducted in MEDLINE, Embase, CINAHL, The Cochrane Library, Web of Science, and Google Scholar. Guidelines, trial registries, and gray literature were also searched. Databases were searched from inception to January 20, 2022.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials and controlled nonrandomized studies were eligible if they assessed interventions aimed at encouraging awareness of fetal movement or fetal movement counting and/or improving the subsequent clinical management of reduced fetal movement. Eligible populations were singleton pregnancies after 24 completed weeks of gestation. The primary review outcome was stillbirth; a number of secondary maternal and neonatal outcomes were specified in the review.

METHODS

Risk of bias was assessed using the Cochrane Risk of Bias 2 and Risk of Bias in Non-Randomized Studies I tools for randomized controlled trials and nonrandomized studies, respectively. Variation caused by heterogeneity was assessed using I². Data from studies employing similar interventions were combined using random effects meta-analysis.

RESULTS

A total of 1609 citations were identified; 190 full-text articles were evaluated against the inclusion criteria, 18 studies (16 randomized controlled trials and 2 nonrandomized studies) were included. The evidence is uncertain about the effect of encouraging awareness of fetal movement on stillbirth when compared with standard care (2 studies, n=330,084) with a pooled adjusted odds ratio of 1.19 (95% confidence interval, 0.96-1.47). Interventions for encouraging awareness of fetal movement may be associated with a reduction in neonatal intensive care unit admissions and Apgar scores of <7 at 5 minutes of age and may not be associated with increases in cesarean deliveries or induction of labor. The evidence is uncertain about the effect of encouraging fetal movement counting on stillbirth when compared with standard care with a pooled odds ratio of 0.69 (95% confidence interval, 0.18-2.65) based on data from 3 randomized controlled trials (n=70,584). Counting fetal movements may increase maternal-fetal attachment and decrease anxiety when compared with standard care. When comparing combined interventions of fetal movement awareness and subsequent clinical management with standard care (1 study, n=393,857), the evidence is uncertain about the effect on stillbirth (adjusted odds ratio, 0.86; 95% confidence interval, 0.70-1.05).

CONCLUSION

The effect of interventions for encouraging awareness of reduced fetal movement alone or in combination with subsequent clinical management on stillbirth is uncertain. Encouraging awareness of fetal movement may be associated with reduced adverse neonatal outcomes without an increase in interventions in labor. The meta-analysis was hampered by variations in interventions, outcome reporting, and definitions. Individual studies are frequently underpowered to detect a reduction in severe, rare outcomes and no studies were included from high-burden settings. Studies from such settings are needed to determine whether interventions can reduce stillbirth.

Management of reduced fetal movement: A comparative analysis of two audits at a tertiary care clinical service

OBJECTIVES

Reduced fetal movement (RFM) is a commonly presenting worrisome complaint, both for mothers and attending clinicians. The aim of this study was to review the management of RFM before and following the implementation of new hospital guideline and to determine pregnancy outcomes following single vs repeated consultations with complaints of RFM. We also compared the standards in our old and new trust guidelines against published guidance from the Royal College of Obstetricians and Gynaecologists (RCOG).

STUDY DESIGN

This retrospective cohort study was conducted between June -November 2016 (audit 1) and July- December 2018 (audit 2). All women with a non-anomalous singleton pregnancy, attending the Day Assessment Unit of the Jessop Wing Hospital Sheffield UK with a primary presentation of perceived RFM after 24 weeks of gestation were included. The electronic maternity database was used to collect information regarding their presentations and pregnancy outcomes. Adherence to the old and the new local guidelines for the respective epochs of the assessment were reviewed by two independent observers using the Appraisal of Guidelines for Research and Evaluation (AGREE) 11 tool.

RESULTS

A total of 1775 women presented with RFM during the two study periods. Of these, 632 attended with more than 1 presentation of RFM (35.6 %). There were 3 stillbirths; all diagnosed at the first presentation with RFM. In the second audit, prevalence of RFM increased by 10 %, CTG documentation improved by 1% and ultrasound scan requests decreased by 6.6 %. Women with more than one episode of RFM were more likely to be younger, smokers, nulliparous, have raised BMI, had a higher IOL rate and had more ultrasound scans compared to those with one episode. However, neonatal outcome, onset of labour and mode of delivery remained unchanged between the two groups. While the RCOG guideline was superior to both (old and new) guidelines, the overall scores increased in the new guideline by 22 %.

CONCLUSION

After implementing the new guideline, the re-audit demonstrates a reduction in the number of requested ultrasound scans without any compromise on the perinatal outcome.

Standard care informed by the result of a placental growth factor blood test versus standard care alone in women with reduced fetal movement at or after 36+0 weeks' gestation: a pilot randomised controlled trial

Background

Biomarkers of placental function can potentially aid the diagnosis and prediction of pregnancy complications. This randomised controlled pilot trial assessed whether for women with reduced fetal movement (RFM), intervention directed by the measurement of a placental biomarker in addition to standard care was feasible and improved pregnancy outcome compared with standard care alone.

Methods

Women aged 16–50 years presenting at eight UK maternity units with RFM between 36⁺⁰ and 41⁺⁰ weeks’ gestation with a viable singleton pregnancy and no indication for immediate delivery were eligible. Participants were randomised 1:1 in an unblinded manner to standard care and a biomarker blood test result revealed and acted on (intervention arm) or standard care where the biomarker result was not available (control arm). The objectives were to determine the feasibility of a main trial by recruiting 175–225 participants over 9 months and to provide proof of concept that informing care by measurement of placental biomarkers may improve outcome. Feasibility was assessed via the number of potentially eligible women, number recruited, reasons for non-recruitment and compliance. Proof of concept outcomes included the rates of the induction of labour and caesarean birth, and a composite adverse pregnancy outcome.

Results

Overall, 2917 women presented with RFM ≥ 36 weeks, 352 were approached to participate and 216 (61%) were randomised (intervention n = 109, control n = 107). The main reason for not approaching women was resource/staff issues (n = 1510). Ninety-seven women declined the trial, mainly due to not liking blood tests (n = 24) or not wanting to be in a trial (n = 21). Compliance with the trial interventions was 100% in both arms. Labour was induced in 97 (45%) participants (intervention n = 49, control n = 48), while 17 (9%) had planned caesarean sections (intervention n = 9, control n = 8). Overall, 9 (8%) babies in the intervention arm had the composite adverse pregnancy outcome versus 4 (4%) in the control arm.

Conclusions

A main trial using a placental biomarker in combination with delivery, as indicated by the biomarker, in women with RFM is feasible. The frequency of adverse outcomes in this population is low, hence, a large sample size would be required along with consideration of the most appropriate outcome measures.

Trial registration

ISRCTN, ISRCTN12067514; registered 8 September 2017.

Intra-placental arterial Doppler: A marker of fetoplacental vascularity in late-onset placental disease?

INTRODUCTION

Late-gestation adverse pregnancy outcome is associated with reduced placental villous vascularity but rarely with a frankly abnormal umbilical artery Doppler waveform. The clinical utility of umbilical artery Doppler velocimetry in late gestation is limited by poor understanding of what aspect(s) of placental structure and function the impedance reflects. We hypothesized that placental arterial circulation impedance reflects placental vascularity and arterial function.

MATERIAL AND METHODS

This was a secondary analysis of data from the FEMINA2 study, a study of pregnancy outcome after reduced fetal movement. Forty-three pregnancies that delivered within 7 days of ultrasound assessment were examined. Impedance was quantified by pulsatility index (PI) from umbilical, chorionic plate arteries, and intra-placental arteries. Site-specific PI was compared with villous vascularity (CD31 immunostaining) and placental arterial function (wire myography) by regression analysis (P < .01) where factor analysis suggested potential co-variance (Eigen value > 2).

RESULTS

Pulsatility index decreased with proximity to the placental microvasculature (P < .0001). Intra-placental artery PI correlated significantly with vessel number (R²  = 0.40, P = .0007). No significant relations between umbilical or chorionic plate artery PI and villous vascularity were found (P ≥ .11 and P ≥ .042). No significant co-variance was suggested between PI at any Doppler sampling site and ex vivo placental arterial function indices. Measurement reliability (intraclass correlation coefficient) was highest in the umbilical artery (PI 0.75 and 0.50 for intra- and interoperator reliability, respectively) and lowest in the intra-placental arteries (PI 0.55 and 0.41, respectively). Systematic bias in umbilical artery PI was observed between observers, but not at other Doppler sampling sites.

CONCLUSIONS

More vascular placentas ex vivo are associated with reduced intra-placental artery Doppler impedance in utero. Although umbilical (but not intra-placental) artery Doppler PI is associated with adverse outcome after reduced fetal movement, this predictive ability does not appear to be through assessment of placental vascularity or chorionic plate arterial function. The inferior reliability of intra-placental artery Doppler, although similar to previously published reliability of umbilical artery Doppler, impairs its ability to detect subtle differences in placental vascularity, and must be significantly improved before it could be considered a clinically useful test.

Decreased fetal movements: Perinatal and long-term neurological outcomes

BACKGROUND

While maternal perception of decreased fetal movements during advanced stages of pregnancy may be an indicator for adverse perinatal outcome, the long-term neurological outcome of offspring of affected pregnancies remains largely unknown.

OBJECTIVE

To examine whether maternal complaint of decreased fetal movements is associated with adverse perinatal outcomes, and to assess the implications of decreased fetal movements on long-term neurological morbidity of the offspring.

STUDY DESIGN

A single center cohort analysis including deliveries between the years 1991-2014 was conducted. The association between decreased fetal movements and adverse perinatal outcome was evaluated using a general estimation equation (GEE) multivariable analyses. Incidence of hospitalizations (up to age 18 years) due to various neurological conditions was compared between offspring of affected pregnancies, and those who were not, using a Kaplan-Meyer survival curve. A Cox proportional hazards model was used to control for confounders.

RESULTS

439 (0.18%) of 242,342 deliveries included in this study were accompanied by maternal complaint of decreased fetal movements. Perinatal outcome was comparable between the groups, with no cases of perinatal mortality observed among the exposed group. Total neurological-related hospitalization rate of the offspring, as well as hospitalizations due to movement disorders, were higher among the exposed group (Kaplan-Meyer log-rank test P < 0.05). This association between decreased fetal movements and increased long-term neurological hospitalization proved to be independent of potential confounders with an adjusted hazard ratio of 1.54 (95% CI 1.0-2.37).

CONCLUSION

Maternal complaint of decreased fetal movements does not predict adverse perinatal outcome but is associated with an elevated risk for long-term neurological morbidity of the offspring.

Biochemical tests of placental function versus ultrasound assessment of fetal size for stillbirth and small-for-gestational-age infants

BACKGROUND

Stillbirth affects 2.6 million pregnancies worldwide each year. Whilst the majority of cases occur in low- and middle-income countries, stillbirth remains an important clinical issue for high-income countries (HICs) - with both the UK and the USA reporting rates above the mean for HICs. In HICs, the most frequently reported association with stillbirth is placental dysfunction. Placental dysfunction may be evident clinically as fetal growth restriction (FGR) and small-for-dates infants. It can be caused by placental abruption or hypertensive disorders of pregnancy and many other disorders and factorsPlacental abnormalities are noted in 11% to 65% of stillbirths. Identification of FGA is difficult in utero. Small-for-gestational age (SGA), as assessed after birth, is the most commonly used surrogate measure for this outcome. The degree of SGA is associated with the likelihood of FGR; 30% of infants with a birthweight < 10th centile are thought to be FGR, while 70% of infants with a birthweight < 3rd centile are thought to be FGR. Critically, SGA is the most significant antenatal risk factor for a stillborn infant. Correct identification of SGA infants is associated with a reduction in the perinatal mortality rate. However, currently used tests, such as measurement of symphysis-fundal height, have a low reported sensitivity and specificity for the identification of SGA infants.

OBJECTIVES

The primary objective was to assess and compare the diagnostic accuracy of ultrasound assessment of fetal growth by estimated fetal weight (EFW) and placental biomarkers alone and in any combination used after 24 weeks of pregnancy in the identification of placental dysfunction as evidenced by either stillbirth, or birth of a SGA infant. Secondary objectives were to investigate the effect of clinical and methodological factors on test performance.

SEARCH METHODS

We developed full search strategies with no language or date restrictions. The following sources were searched: MEDLINE, MEDLINE In Process and Embase via Ovid, Cochrane (Wiley) CENTRAL, Science Citation Index (Web of Science), CINAHL (EBSCO) with search strategies adapted for each database as required; ISRCTN Registry, UK Clinical Trials Gateway, WHO International Clinical Trials Portal and ClinicalTrials.gov for ongoing studies; specialist abstract and conference proceeding resources (British Library's ZETOC and Web of Science Conference Proceedings Citation Index). Search last conducted in Ocober 2016.

SELECTION CRITERIA

We included studies of pregnant women of any age with a gestation of at least 24 weeks if relevant outcomes of pregnancy (live birth/stillbirth; SGA infant) were assessed. Studies were included irrespective of whether pregnant women were deemed to be low or high risk for complications or were of mixed populations (low and high risk). Pregnancies complicated by fetal abnormalities and multi-fetal pregnancies were excluded as they have a higher risk of stillbirth from non-placental causes. With regard to biochemical tests, we included assays performed using any technique and at any threshold used to determine test positivity.

DATA COLLECTION AND ANALYSIS

We extracted the numbers of true positive, false positive, false negative, and true negative test results from each study. We assessed risk of bias and applicability using the QUADAS-2 tool. Meta-analyses were performed using the hierarchical summary ROC model to estimate and compare test accuracy.

MAIN RESULTS

We included 91 studies that evaluated seven tests - blood tests for human placental lactogen (hPL), oestriol, placental growth factor (PlGF) and uric acid, ultrasound EFW and placental grading and urinary oestriol - in a total of 175,426 pregnant women, in which 15,471 pregnancies ended in the birth of a small baby and 740 pregnancies which ended in stillbirth. The quality of included studies was variable with most domains at low risk of bias although 59% of studies were deemed to be of unclear risk of bias for the reference standard domain. Fifty-three per cent of studies were of high concern for applicability due to inclusion of only high- or low-risk women.Using all available data for SGA (86 studies; 159,490 pregnancies involving 15,471 SGA infants), there was evidence of a difference in accuracy (P < 0.0001) between the seven tests for detecting pregnancies that are SGA at birth. Ultrasound EFW was the most accurate test for detecting SGA at birth with a diagnostic odds ratio (DOR) of 21.3 (95% CI 13.1 to 34.6); hPL was the most accurate biochemical test with a DOR of 4.78 (95% CI 3.21 to 7.13). In a hypothetical cohort of 1000 pregnant women, at the median specificity of 0.88 and median prevalence of 19%, EFW, hPL, oestriol, urinary oestriol, uric acid, PlGF and placental grading will miss 50 (95% CI 32 to 68), 116 (97 to 133), 124 (108 to 137), 127 (95 to 152), 139 (118 to 154), 144 (118 to 161), and 144 (122 to 161) SGA infants, respectively. For the detection of pregnancies ending in stillbirth (21 studies; 100,687 pregnancies involving 740 stillbirths), in an indirect comparison of the four biochemical tests, PlGF was the most accurate test with a DOR of 49.2 (95% CI 12.7 to 191). In a hypothetical cohort of 1000 pregnant women, at the median specificity of 0.78 and median prevalence of 1.7%, PlGF, hPL, urinary oestriol and uric acid will miss 2 (95% CI 0 to 4), 4 (2 to 8), 6 (6 to 7) and 8 (3 to 13) stillbirths, respectively. No studies assessed the accuracy of ultrasound EFW for detection of pregnancy ending in stillbirth.

AUTHORS' CONCLUSIONS

Biochemical markers of placental dysfunction used alone have insufficient accuracy to identify pregnancies ending in SGA or stillbirth. Studies combining U and placental biomarkers are needed to determine whether this approach improves diagnostic accuracy over the use of ultrasound estimation of fetal size or biochemical markers of placental dysfunction used alone. Many of the studies included in this review were carried out between 1974 and 2016. Studies of placental substances were mostly carried out before 1991 and after 2013; earlier studies may not reflect developments in test technology.

Antenatal placental assessment in the prediction of adverse pregnancy outcome after reduced fetal movement

OBJECTIVE

To assess the value of in utero placental assessment in predicting adverse pregnancy outcome after reported reduced fetal movements (RFM).

METHOD

A non-interventional prospective cohort study of women (N = 300) with subjective RFM at ≥28 weeks' gestation in singleton non-anomalous pregnancies at a UK tertiary maternity hospital. Clinical, sonographic (fetal weight, placental size and maternal, fetal and placental arterial Doppler) and biochemical (maternal serum hCG, hPL, progesterone, PlGF and sFlt-1) assessment was conducted. Multiple logistic regression identified combinations of measurements (models) most predictive of adverse pregnancy outcome (perinatal mortality, birth weight <10th centile, five minute Apgar score <7, umbilical arterial pH <7.1 or base excess <-10, neonatal intensive care admission). Models were compared by test performance characteristics (ROC curve, sensitivity, specificity, positive/negative predictive value, positive/negative likelihood ratios) against baseline care (estimated fetal weight centile, amniotic fluid index and gestation at presentation).

RESULTS

61 (20.6%) pregnancies ended in adverse outcome. Models incorporating PlGF/sFlt-1 ratio and umbilical artery free loop Doppler impedance demonstrated modest improvement in ROC area for adverse outcome (baseline care 0.69 vs. proposed models 0.73-0.76, p<0.05). However, there was little improvement in other test characteristics (baseline vs. best proposed model: sensitivity 21.7% [95% confidence interval 13.1-33.6] vs. 35.8%% [24.4-49.3], specificity 96.6% [93.4-98.3] vs. 94.7% [90.7-97.0], PPV 61.9% [40.9-79.3] vs. 63.3% [45.5-78.1], NPV 82.8% [77.9-86.8] vs. 85.2% [80.0-89.2], positive LR 6.3 [2.8-14.6] vs. 6.7 [3.4-3.3], negative LR 0.81 [0.71-0.93] vs. 0.68 [0.55-0.83]) and wide confidence intervals. Negative post-test probability remained high (16.7% vs. 14.0%).

CONCLUSION

Antenatal placental assessment may improve identification of RFM pregnancies at highest risk of adverse pregnancy outcome but further work is required to understand and refine currently available outcome definitions and diagnostic techniques to improve clinical utility.

Reduced fetal movement intervention Trial-2 (ReMIT-2): protocol for a pilot randomised controlled trial of standard care informed by the result of a placental growth factor (PlGF) blood test versus standard care alone in women presenting with reduced fetal movement at or after 36+ 0 weeks gestation

BACKGROUND

Forty percent of babies who are stillborn born die after 36 weeks gestation and have no lethal structural abnormality. Maternal perception of reduced fetal movement (RFM) is associated with stillbirth and is related to abnormal placental structure and function. The ultimate objective of this trial is to assess whether for women with RFM, intervention directed by measurement of placental biochemical factors in addition to standard care improves pregnancy outcome compared with standard care alone. This is the protocol for a pilot trial to determine the feasibility of a definitive trial and also provide proof of concept that informing care by measurement of placental factors improves neonatal outcomes.

METHODS

ReMIT-2 is a multicentre, pilot randomised controlled trial of care informed by results of an additional placental factor blood test versus standard care alone for women presenting with RFM at or after 36+ 0 weeks gestation. Participants will be randomised 1:1 to the intervention arm where the blood test result is revealed and acted on, or to the control arm where the blood sample is not tested immediately and therefore the result cannot be acted on. All participants will be followed up six weeks after delivery to assess their health status and views of the trial, along with healthcare costs. A sub-group will be interviewed within 16 weeks after delivery to further explore their views of the trial. Outcomes to determine feasibility of a definitive trial include number of potentially eligible women, proportion lost to follow-up, clinical characteristics at randomisation, reasons for non-recruitment, compliance with the trial intervention and views of participants and clinicians about the trial. Proof of concept outcomes include: rates of induction of labour; Caesarean birth; and a composite neonatal outcome of stillbirths and deaths before discharge, 5-min Apgar score < 7, umbilical artery pH < 7.05 and admission to neonatal unit for > 48 h.

DISCUSSION

Results from this pilot trial will help determine whether a large definitive trial is feasible. Such a study would provide evidence to guide management of women with RFM and reduce stillbirths.

TRIAL REGISTRATION

ISRCTN Registry, ISRCTN12067514 . Registered on 8 September 2017.

CONSORT 2010 statement: extension to randomised pilot and feasibility trials

The Consolidated Standards of Reporting Trials (CONSORT) statement is a guideline designed to improve the transparency and quality of the reporting of randomised controlled trials (RCTs). In this article we present an extension to that statement for randomised pilot and feasibility trials conducted in advance of a future definitive RCT. The checklist applies to any randomised study in which a future definitive RCT, or part of it, is conducted on a smaller scale, regardless of its design (eg, cluster, factorial, crossover) or the terms used by authors to describe the study (eg, pilot, feasibility, trial, study). The extension does not directly apply to internal pilot studies built into the design of a main trial, non-randomised pilot and feasibility studies, or phase II studies, but these studies all have some similarities to randomised pilot and feasibility studies and so many of the principles might also apply. The development of the extension was motivated by the growing number of studies described as feasibility or pilot studies and by research that has identified weaknesses in their reporting and conduct. We followed recommended good practice to develop the extension, including carrying out a Delphi survey, holding a consensus meeting and research team meetings, and piloting the checklist. The aims and objectives of pilot and feasibility randomised studies differ from those of other randomised trials. Consequently, although much of the information to be reported in these trials is similar to those in randomised controlled trials (RCTs) assessing effectiveness and efficacy, there are some key differences in the type of information and in the appropriate interpretation of standard CONSORT reporting items. We have retained some of the original CONSORT statement items, but most have been adapted, some removed, and new items added. The new items cover how participants were identified and consent obtained; if applicable, the prespecified criteria used to judge whether or how to proceed with a future definitive RCT; if relevant, other important unintended consequences; implications for progression from pilot to future definitive RCT, including any proposed amendments; and ethical approval or approval by a research review committee confirmed with a reference number. This article includes the 26 item checklist, a separate checklist for the abstract, a template for a CONSORT flowchart for these studies, and an explanation of the changes made and supporting examples. We believe that routine use of this proposed extension to the CONSORT statement will result in improvements in the reporting of pilot trials. Editor's note: In order to encourage its wide dissemination this article is freely accessible on the BMJ and Pilot and Feasibility Studies journal websites.

Defining Feasibility and Pilot Studies in Preparation for Randomised Controlled Trials: Development of a Conceptual Framework

We describe a framework for defining pilot and feasibility studies focusing on studies conducted in preparation for a randomised controlled trial. To develop the framework, we undertook a Delphi survey; ran an open meeting at a trial methodology conference; conducted a review of definitions outside the health research context; consulted experts at an international consensus meeting; and reviewed 27 empirical pilot or feasibility studies. We initially adopted mutually exclusive definitions of pilot and feasibility studies. However, some Delphi survey respondents and the majority of open meeting attendees disagreed with the idea of mutually exclusive definitions. Their viewpoint was supported by definitions outside the health research context, the use of the terms 'pilot' and 'feasibility' in the literature, and participants at the international consensus meeting. In our framework, pilot studies are a subset of feasibility studies, rather than the two being mutually exclusive. A feasibility study asks whether something can be done, should we proceed with it, and if so, how. A pilot study asks the same questions but also has a specific design feature: in a pilot study a future study, or part of a future study, is conducted on a smaller scale. We suggest that to facilitate their identification, these studies should be clearly identified using the terms 'feasibility' or 'pilot' as appropriate. This should include feasibility studies that are largely qualitative; we found these difficult to identify in electronic searches because researchers rarely used the term 'feasibility' in the title or abstract of such studies. Investigators should also report appropriate objectives and methods related to feasibility; and give clear confirmation that their study is in preparation for a future randomised controlled trial designed to assess the effect of an intervention.

Use of biochemical tests of placental function for improving pregnancy outcome

BACKGROUND

The placenta has an essential role in determining the outcome of pregnancy. Consequently, biochemical measurement of placentally-derived factors has been suggested as a means to improve fetal and maternal outcome of pregnancy.

OBJECTIVES

To assess whether clinicians' knowledge of the results of biochemical tests of placental function is associated with improvement in fetal or maternal outcome of pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 July 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised, cluster-randomised or quasi-randomised controlled trials assessing the merits of the use of biochemical tests of placental function to improve pregnancy outcome.Studies were eligible if they compared women who had placental function tests and the results were available to their clinicians with women who either did not have the tests, or the tests were done but the results were not available to the clinicians. The placental function tests were any biochemical test of placental function carried out using the woman's maternal biofluid, either alone or in combination with other placental function test/s.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, extracted data and assessed trial quality. Authors of published trials were contacted for further information.

MAIN RESULTS

Three trials were included, two quasi-randomised controlled trials and one randomised controlled trial. One trial was deemed to be at low risk of bias while the other two were at high risk of bias. Different biochemical analytes were measured - oestrogen was measured in one trial and the other two measured human placental lactogen (hPL). One trial did not contribute outcome data, therefore, the results of this review are based on two trials with 740 participants.There was no evidence of a difference in the incidence of death of a baby (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.36 to 2.13, two trials, 740 participants (very low quality evidence)) or the frequency of a small-for-gestational-age infant (RR 0.44, 95% CI 0.16 to 1.19, one trial, 118 participants (low quality evidence)).In terms of this review's secondary outcomes, there was no evidence of a clear difference between women who had biochemical tests of placental function compared with standard antenatal care for the incidence of stillbirth (RR 0.56, 95% CI 0.16 to 1.88, two trials, 740 participants (very low quality evidence)) or neonatal death (RR 1.62, 95% CI 0.39 to 6.74, two trials, 740 participants, very low quality evidence)) although the directions of any potential effect were in opposing directions. There was no evidence of a difference between groups in elective delivery (RR 0.98, 95% CI 0.84 to 1.14, two trials, 740 participants (low quality evidence)), caesarean section (one trial, RR 0.48, 95% CI 0.15 to 1.52, one trial, 118 participants (low quality evidence)), change in anxiety score (mean difference -2.40, 95% CI -4.78 to -0.02, one trial, 118 participants), admissions to neonatal intensive care (RR 0.32, 95% CI 0.03 to 3.01, one trial, 118 participants), and preterm birth before 37 weeks' gestation (RR 2.90, 95% CI 0.12 to 69.81, one trial, 118 participants). One trial (118 participants) reported that there were no cases of serious neonatal morbidity. Maternal death was not reported.A number of this review's secondary outcomes relating to the baby were not reported in the included studies, namely: umbilical artery pH < 7.0, neonatal intensive care for more than seven days, very preterm birth (< 32 weeks' gestation), need for ventilation, organ failure, fetal abnormality, neurodevelopment in childhood (cerebral palsy, neurodevelopmental delay). Similarly, a number of this review's maternal secondary outcomes were not reported in the included studies (admission to intensive care, high dependency unit admission, hospital admission for > seven days, pre-eclampsia, eclampsia, and women's perception of care).

AUTHORS' CONCLUSIONS

There is insufficient evidence to support the use of biochemical tests of placental function to reduce perinatal mortality or increase identification of small-for-gestational-age infants. However, we were only able to include data from two studies that measured oestrogens and hPL. The quality of the evidence was low or very low.Two of the trials were performed in the 1970s on women with a variety of antenatal complications and this evidence cannot be generalised to women at low-risk of complications or groups of women with specific pregnancy complications (e.g. fetal growth restriction). Furthermore, outcomes described in the 1970s may not reflect what would be expected at present. For example, neonatal mortality rates have fallen substantially, such that an infant delivered at 28 weeks would have a greater chance of survival were those studies repeated; this may affect the primary outcome of the meta-analysis.With data from just two studies (740 women), this review is underpowered to detect a difference in the incidence of death of a baby or the frequency of a small-for-gestational-age infant as these have a background incidence of approximately 0.75% and 10% of pregnancies respectively. Similarly, this review is underpowered to detect differences between serious and/or rare adverse events such as severe neonatal morbidity. Two of the three included studies were quasi-randomised, with significant risk of bias from group allocation. Additionally, there may be performance bias as in one of the two studies contributing data, participants receiving standard care did not have venepuncture, so clinicians treating participants could identify which arm of the study they were in. Future studies should consider more robust randomisation methods and concealment of group allocation and should be adequately powered to detect differences in rare adverse events.The studies identified in this review examined two different analytes: oestrogens and hPL. There are many other placental products that could be employed as surrogates of placental function, including: placental growth factor (PlGF), human chorionic gonadotrophin (hCG), plasma protein A (PAPP-A), placental protein 13 (PP-13), pregnancy-specific glycoproteins and progesterone metabolites and further studies should be encouraged to investigate these other placental products. Future randomised controlled trials should test analytes identified as having the best predictive reliability for placental dysfunction leading to small-for-gestational-age infants and perinatal mortality.

Placental Features of Late-Onset Adverse Pregnancy Outcome

Objective

Currently, no investigations reliably identify placental dysfunction in late pregnancy. To facilitate the development of such investigations we aimed to identify placental features that differ between normal and adverse outcome in late pregnancy in a group of pregnancies with reduced fetal movement.

Methods

Following third trimester presentation with reduced fetal movement (N = 100), placental structure ex vivo was measured. Placental function was then assessed in terms of (i) chorionic plate artery agonist responses and length-tension characteristics using wire myography and (ii) production and release of placentally derived hormones (by quantitative polymerase chain reaction and enzyme linked immunosorbant assay of villous tissue and explant conditioned culture medium).

Results

Placentas from pregnancies ending in adverse outcome (N = 23) were ~25% smaller in weight, volume, length, width and disc area (all p<0.0001) compared with those from normal outcome pregnancies. Villous and trophoblast areas were unchanged, but villous vascularity was reduced (median (interquartile range): adverse outcome 10 (10–12) vessels/mm² vs. normal outcome 13 (12–15), p = 0.002). Adverse outcome pregnancy placental arteries were relatively insensitive to nitric oxide donated by sodium nitroprusside compared to normal outcome pregnancy placental arteries (50% Effective Concentration 30 (19–50) nM vs. 12 (6–24), p = 0.02). Adverse outcome pregnancy placental tissue contained less human chorionic gonadotrophin (20 (11–50) vs. 55 (24–102) mIU/mg, p = 0.007) and human placental lactogen (11 (6–14) vs. 27 (9–50) mg/mg, p = 0.006) and released more soluble fms-like tyrosine kinase-1 (21 (13–29) vs. 5 (2–15) ng/mg, p = 0.01) compared with normal outcome pregnancy placental tissue.

Conclusion

These data provide a description of the placental phenotype of adverse outcome in late pregnancy. Antenatal tests that accurately reflect elements of this phenotype may improve its prediction.

IFPA Gábor Than Award Lecture: Recognition of placental failure is key to saving babies' lives

In high-income countries, placental failure is implicated in up to 65% of cases of stillbirth. Placental failure describes the situation where the placenta cannot meet the fetus' needs and may be the end-result of a variety of underlying pathological processes evident in the placental disc, membranes and umbilical cord. These include lesions with genetic, environmental, infectious, inflammatory, mechanical, metabolic, traumatic or vascular origin. Investigation of placental tissue from stillbirths and from pregnancies at an increased risk of stillbirth has demonstrated changes in macroscopic and microscopic structure which are themselves related to abnormal placental function. A better understanding and identification of placental failure may improve the management of pregnancy complications and of pregnancies after stillbirth (which have a 5-fold increased risk of stillbirth). The majority of current antenatal tests focus on the fetus and its response to the intrauterine environment; few of these investigations reduce stillbirths in low-risk pregnancies. However, some currently used investigations reflect placental development, structure and vascular function, while other investigations employed in clinical research settings such as the evaluation of placental structure and shape have a good predictive value for adverse fetal outcome. In addition, recent studies suggest that biomarkers of placental inflammation and deteriorating placental function can be detected in maternal blood suggesting that holistic evaluation of placental structure and function is possible. We anticipate that development of reliable tests of placental structure and function, coupled to assessment of fetal wellbeing offer a new opportunity to identify pregnancies at risk of stillbirth and to direct novel therapeutic strategies to prevent it.

Pregnancy outcomes with a primary complaint of perception of reduced fetal movements

Reduced fetal movement is a worrisome common complaint, not only for mothers but also for the attending medical personnel. The aim of this study was to analyse the pregnancy outcomes of women who presented primarily with reduced fetal movements (RFM). A retrospective study was performed based on patients' perception alone. Obstetric, past medical history, current presentation and outcomes of pregnancy were analysed. A total of 230 case notes were reviewed, with the majority being primigravidae. Less than half (48.7%) of the women had spontaneous labour, 45.7% had induction and 5.6% had elective caesarean section. There were no maternal complications in 97.4% (n = 224) of them. About 0.9% (n = 2) and 1.7% (n = 4) had primary postpartum haemorrhage and extended perineal tear, respectively. Although there was no major neonatal mortality and morbidity, until a randomised trial with a significant sample is conducted in the management of RFM, careful selections for elective delivery or conservative management would prevent untoward complications.

MANAGEMENT OF REDUCED FETAL MOVEMENTS

Reduced fetal movement (RFM) is commonly defined as any reduction in maternal perception of fetal activity. Perceived fetal activity may be movement of limbs, trunk or head movement, but excludes fetal hiccoughs (as this is involuntary movement). The perception of fetal movement by an expectant mother is the first, and ongoing, non-sonographic indicator of fetal viability. The “normal” pattern of fetal movements varies from pregnancy to pregnancy, and often does not become established until 28 weeks’ gestation. Many babies have particularly active periods of the day, usually corresponding to periods of maternal rest and inactivity (which may in itself reflect increased maternal awareness of fetal movement). A variable percentage of sonographically observed fetal movements are perceived by prospective mothers (commonly 30–40%, although some studies report rates as high as 80%).