Small-for-gestational-age babies after 37 weeks: impact study of risk-stratification protocol

Adverse perinatal outcomes are strongly associated with degree of abnormality in uterine artery Doppler pulsatility index

OBJECTIVE

To investigate the association between varying degrees of abnormality in the Doppler uterine artery pulsatility index (UtA-PI) and adverse perinatal outcome.

METHODS

This was a prospective study of women with a singleton, non-anomalous pregnancy in whom UtA-PI was measured universally in midpregnancy and who gave birth in Oxford University Hospitals, Oxford, UK, between 2016 and 2023. Relative risk ratios (RRR) for the primary outcomes of extended perinatal mortality and live birth with a severe small-for-gestational-age (SGA) neonate were calculated using multinomial logistic regression, for early preterm birth (before 34 + 0 weeks' gestation) and late preterm/term birth (at or after 34 + 0 weeks). Risks were also investigated for iatrogenic preterm birth and a composite adverse outcome before 34 + 0 weeks.

RESULTS

Overall, 33 364 pregnancies were included in the analysis. Compared to those with a normal UtA-PI, the risk of extended perinatal mortality with delivery before 34 + 0 weeks was higher in women with UtA-PI ≥ 90th percentile (RRR, 4.7 (95% CI, 2.7-8.0); P < 0.001), but this was not demonstrated in births at or after 34 + 0 weeks. The risk of live birth with severe SGA was associated strongly with abnormal UtA-PI for early births (RRR, 26.0 (95% CI, 11.6-58.2); P < 0.001) and later births (RRR, 2.3 (95% CI, 1.8-2.9); P < 0.001). Women with raised UtA-PI were more likely to have an early iatrogenic birth (RRR, 7.8 (95% CI, 5.5-11.2); P < 0.001). For each outcome before 34 + 0 weeks and the composite outcome, the risk increased significantly in association with the degree of abnormality in the UtA-PI (from < 90th, 90-94th, 95-98th to ≥ 99th percentile) (Ptrend < 0.001). When using the 90th percentile as opposed to the 95th, there was a significant improvement in the overall predictive accuracy (as determined by the area under the receiver-operating-characteristics curve) for the composite adverse outcome (χ2 = 6.64, P = 0.01) and iatrogenic preterm birth (χ2 = 4.10, P = 0.04).

CONCLUSIONS

Elevated UtA-PI is a key predictor of iatrogenic preterm birth, severe SGA and perinatal loss up to 34 + 0 weeks' gestation. The 90th percentile for UtA-PI should be used, and management should be tailored according to the degree of abnormality, as pregnancies with very raised UtA-PI measurement constitute a group at extreme risk of adverse outcome. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Clinical decision support systems for maternity care: a systematic review and meta-analysis

Background

The use of Clinical Decision Support Systems (CDSS) is increasing throughout healthcare and may be able to improve safety and outcomes in maternity care, but maternity care has key differences to other disciplines that complicate the use of CDSS. We aimed to identify evaluated CDSS and synthesise evidence of their impact on maternity care.

Methods

We conducted a systematic review for articles published before 24th May 2024 that described i) CDSS that ii) investigated the impact of their use iii) in maternity settings. Medline, CINAHL, CENTRAL and HMIC were searched for articles relating to evaluations of CDSS in maternity settings, with forward- and backward-citation tracing conducted for included articles. Risk of bias was assessed using the Mixed Methods Assessment Tool, and CDSS were described according to the clinical problem, purpose, design, and technical environment. Quantitative results from articles reporting appropriate data were meta-analysed to estimate odds of a CDSS achieving its desired outcome using a multi-level random effects model, first by individual CDSS and then across all CDSS. PROSPERO ID: CRD42022348157.

Findings

We screened 12,039 papers and included 87 articles describing 47 unique CDSS. 24 articles (28%) described randomised controlled trials, 30 (34%) described non-randomised interventional studies, 10 (11%) described mixed methods studies, 10 (11%) described qualitative studies, 7 (8%) described quantitative descriptive studies, and 7 (8%) described economic evaluations. 49 (56%) were in High-Income Countries and 38 (44%) in Low- and Middle-Income countries, with no CDSS trialled in both income categories. Meta-analysis of 35 included studies found an odds ratio for improved outcomes of 1.69 (95% confidence interval 1.24-2.30). There was substantial variation in effects, aims, CDSS types, context, study designs, and outcomes.

Interpretation

Most CDSS evaluations showed improvements in outcomes, but there was heterogeneity in all aspects of design and evaluation of systems. CDSS are increasingly important in delivering healthcare, and Electronic Health Records and mHealth will increase their availability, but traditional epidemiological methods may be limited in guiding design and demonstrating effectiveness due to rapid CDSS development lifecycles and the complex systems in which they are embedded. Development methods that are attentive to context, such as Human Centred Design, will help to meet this need.

Funding

None.

Abnormal umbilical artery pulsatility index in appropriately grown fetuses in the early third trimester: an observational cohort study

OBJECTIVE

The aim of this study was to determine if appropriately grown fetuses (those that are not small-for-gestational-age) with a raised umbilical artery pulsatility index (>95th centile) in the mid third trimester are at increased risk of placental dysfunction and adverse outcome.

METHODS

This is a 5-year retrospective cohort study using routinely collected data. Inclusion criteria were singleton, non-anomalous pregnancies having a growth scan with umbilical artery Doppler velocimetry between 28 + 0 and 33 + 6 weeks' gestation. Small-for-gestational-age fetuses were excluded. Cases were classified as group 1 (those with an umbilical artery pulsatility index >95th centile at any scan during target window) or group 2 (those where the umbilical artery pulsatility index was ≤95th centile at all scans). p-Values and odds ratios were calculated. Logistic regression was used to compute odds ratios adjusted for baseline estimated weight z-score, gestational age at delivery, and labor induction.

RESULTS

After exclusions, there were 202 pregnancies in group 1 and 7950 in group 2. Differences in baseline characteristics between the groups include age (median age was 30 for group 1 and 32 for group 2, p < .001), smoking (group 1 were more likely to smoke, p < .001) and labor induction (more common in group 1, p = .03). Among those delivering ≥34 + 0, group 1 were more likely to be small-for-gestational-age and have an abnormal cerebro-placental ratio at the final scan (OR 6.76, CI 4.23-10.80 and OR 5.07, CI 3.37-7.63 respectively), and to develop features of growth restriction (OR 9.85, CI 6.27-15.49). Group 1 were also more likely to deliver <37 + 0 weeks' gestation (OR 1.71, CI 1.13-2.58) and to have birthweight <10th or <3rd centile (OR 5.26, CI 3.65-7.58 and OR 6.13, CI 3.00-12.54 respectively). These associations remained significant when adjusted for estimated weight at the initial scan.

CONCLUSIONS

These data suggest that raised umbilical artery pulsatility index in an appropriately grown fetus at 28 + 0 to 33 + 6 weeks' gestation is associated with subsequent development of growth restriction markers and an increased risk of moderate and severe small-for-gestational-age at birth. This is independent of the estimated weight of these babies at the index scan.

Third-trimester uterine artery Doppler for prediction of adverse outcome in late small-and adequate for-gestational-age fetuses

Fetal growth restriction includes all those fetuses that do not reach their own growth potential due to placental insufficiency and therefore at higher risk of adverse perinatal outcomes. Identification and follow-up of these fetuses is essential to decrease this additional risk. Although estimated fetal weight under the 3rd centile and pathological cerebroplacental ratio are the most accepted predictive criteria, some evidence suggests that abnormal uterine artery Doppler may be a useful prognostic parameter in late-onset growth restriction fetuses at the moment of diagnosis. However, its prediction capacity as a standalone parameter is limited. In that context, integrated models of biometric and hemodynamic ultrasound parameters including uterine Doppler have been proposed as an effective approach to stratify the risk and improve perinatal outcomes. Moreover, an association of abnormal uterine artery Doppler and histological findings of placental underperfusion due to vascular obstruction has been described. Finally, it has also been suggested that the evaluation of uterine artery Doppler at third trimester in appropriate-for-gestational-age fetuses could identify cases of subclinical placental insufficiency, but further evidence is needed to define such predictive strategies.

Management of late-onset fetal growth restriction: pragmatic approach

OBJECTIVES

There is limited prospective evidence to guide the management of late-onset fetal growth restriction (FGR) and its differentiation from small-for-gestational age. The aim of this study was to assess prospectively a novel protocol in which ultrasound criteria were used to classify women with suspected late FGR into two groups: those at low risk, who were managed expectantly until the anticipated date of delivery, and those at high risk, who were delivered soon after 37 weeks of gestation. We also compared the outcome of this prospective cohort with that of a historical cohort of women presenting similarly with suspected late FGR, in order to evaluate the impact of the new protocol.

METHODS

This was a prospective study of women with a non-anomalous singleton pregnancy at ≥ 32 weeks' gestation attending a tertiary hospital in London, UK, between February 2018 and September 2019, with estimated fetal weight (EFW) ≤ 10th centile, or EFW > 10th centile in addition to a decrease in fetal abdominal circumference of ≥ 50 centiles compared with a previous scan, umbilical artery Doppler pulsatility index > 95th centile or cerebroplacental ratio < 5th centile. Women were classified as low or high risk based on ultrasound and Doppler criteria. Women in the low-risk group were delivered by 41 weeks of gestation, unless they subsequently met high-risk criteria, whereas women in the high-risk group (EFW < 3rd centile, umbilical artery Doppler pulsatility index > 95th centile or EFW between 3rd and 10th centiles (inclusive) with abdominal circumference drop or abnormal Dopplers) were delivered at or soon after 37 weeks. The primary outcome was adverse neonatal outcome and included hypothermia, hypoglycemia, neonatal unit admission, jaundice requiring treatment, suspected infection, feeding difficulties, 1-min Apgar score < 7, hospital readmission and any severe adverse neonatal outcome (perinatal death, resuscitation using inotropes or mechanical ventilation, 5-min Apgar score < 7, metabolic acidosis, sepsis, and cerebral, cardiac or respiratory morbidity). Secondary outcomes were adverse maternal outcome (operative delivery for abnormal fetal heart rate) and severe adverse neonatal outcome. Women managed according to the new protocol were compared with a historical cohort of 323 women delivered prior to the implementation of the new protocol, for whom management was guided by individual clinician expertise.

RESULTS

Over 18 months, 321 women were recruited to the prospective cohort, of whom 156 were classified as low risk and 165 were high risk. Adverse neonatal outcome was significantly less common in the low-risk compared with the high-risk group (45% vs 58%; adjusted odds ratio (aOR), 0.6 (95% CI, 0.4-0.9); P = 0.022). There was no significant difference in the rate of adverse maternal outcome (18% vs 24%; aOR, 0.7 (95% CI, 0.4-1.2); P = 0.142) or severe adverse neonatal outcome (3.8% vs 8.5%; aOR, 0.5 (95% CI, 0.2-1.3); P = 0.153) between the low- and high-risk groups. Compared with women in the historical cohort classified retrospectively as low risk, low-risk women managed under the new protocol had a lower rate of adverse neonatal outcome (45% vs 58%; aOR, 0.6 (95% CI, 0.4-0.9); P = 0.026).

CONCLUSIONS

Appropriate risk stratification to guide management of late FGR was associated with a reduced rate of adverse neonatal outcome in low-risk pregnancies. In clinical practice, a policy of expectantly managing women with a low-risk late-onset FGR pregnancy at term could improve neonatal and long-term development. Randomized controlled trials are needed to assess the effect of an evidence-based conservative management protocol for late FGR on perinatal morbidity and mortality and long-term neurodevelopment. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Perinatal Outcome and its Prediction Using Longitudinal Feto-Maternal Doppler Follow-Up in Late Onset Small for Gestational Age Fetuses - A Prospective Cohort Study

PURPOSE

 To describe the perinatal outcome of a prospective cohort of late-onset small-for-gestational-age (SGA) fetuses and to test adverse perinatal outcome (APO) prediction using Doppler measurements.

METHODS

 Singleton pregnancies from 32 weeks with suspicion of SGA (followed-up each 2 weeks) and randomly selected healthy controls at a university hospital were included. The whole SGA group was divided into the FGR subgroup or SGA percentile 3-10 subgroup. The following Doppler measurements were evaluated prospectively: umbilical artery (UA) pulsatility index (PI), middle cerebral artery (MCA) PI, cerebro-placental ratio (CPR), and mean uterine artery (mUtA) PI. APO was defined as arterial cord blood pH ≤ 7.15 and/or 5-minute Apgar ≤ 7 and/or emergency operative delivery and/or admission to the neonatal unit. Induction of labor was indicated according to a stage-based protocol.

RESULTS

 A total of 149 SGA and 143 control fetuses were included. The number of operative deliveries was similar between both groups (control: 29 %, SGA: 28 %), especially the cesarean delivery rate after the onset of labor (11 % vs. 10 %). Most SGA cases ended up in induction of labor (61 % vs. 31 %, p < 0.001). The areas under the curve (AUC) for APO prediction were similar using the last UA PI, MCA PI, CPR, and mUtA PI and barely reached 0.60. The AUC was best for the FGR subgroup, using the minimal CPR or maximum mUtA PI z-score of all longitudinal measurements (AUC = 0.63).

CONCLUSION

 SGA fetuses do not have a higher rate of operative delivery if managed according to a risk stratification protocol. Prediction of APO is best for SGA and FGR using the "worst" CPR or mUtA PI but it remains moderate.

The impact of a universal late third-trimester scan for fetal growth restriction on perinatal outcomes in term singleton births: A prospective cohort study

OBJECTIVE

To investigate perinatal mortality, morbidity and obstetric intervention following the introduction of a universal late third-trimester ultrasound scan for growth restriction.

DESIGN

Prospective cohort study.

SETTING

Oxfordshire (OUH), UK.

POPULATION

Women with a non-anomalous singleton pregnancy undergoing pregnancy care and term delivery at OUH with an estimated due date (EDD) of birth between 1 January 2014 and 30 September 2019.

METHODS

Universal ultrasound for fetal growth restriction between 35⁺⁰ and 36⁺⁶ weeks was introduced in 2016. The outcomes of the next 18 631 eligible term pregnancies were compared, adjusting for covariates and time, with the previous 18 636 who had clinically indicated ultrasounds only. 'Screen-positives' for growth restriction were managed according to a pre-determined protocol which included non-intervention for some small-for-gestational-age babies.

MAIN OUTCOME MEASURES

Extended perinatal mortality, a composite of mortality or encephalopathy Grade II-III, and expedited birth. Other outcomes included composite adverse outcomes used elsewhere, detection of low birthweight and birth from 37⁺⁰ to 38⁺⁶ weeks.

RESULTS

Extended perinatal deaths decreased 27% and severe morbidity decreased 33% but neither change was statistically significant (adjusted odd ratio [aOR] 0.53, 95% confidence interval [C1] 00.18-1.56 and aOR 0.71, 95% CI 0.31-1.63). Expedited births changed from 35.2% to 37.7% (aOR 0.99, 95% CI 0.92-1.06). Birthweight (<10th centile) detection using fetal biometry alone was 31.4% and rose to 40.5% if all abnormal scan parameters were used.

CONCLUSION

Improvements in mortality and severe morbidity subsequent to introducing a universal ultrasound for growth restriction are encouraging but remain unclear. Little change in intervention is possible. The antenatal detection of low birthweight remains poor but improves where markers of growth restriction are used.

Evaluation of the Growth Assessment Protocol (GAP) for antenatal detection of small for gestational age: The DESiGN cluster randomised trial

BACKGROUND

Antenatal detection and management of small for gestational age (SGA) is a strategy to reduce stillbirth. Large observational studies provide conflicting results on the effect of the Growth Assessment Protocol (GAP) in relation to detection of SGA and reduction of stillbirth; to the best of our knowledge, there are no reported randomised control trials. Our aim was to determine if GAP improves antenatal detection of SGA compared to standard care.

METHODS AND FINDINGS

This was a pragmatic, superiority, 2-arm, parallel group, open, cluster randomised control trial. Maternity units in England were eligible to participate in the study, except if they had already implemented GAP. All women who gave birth in participating clusters (maternity units) during the year prior to randomisation and during the trial (November 2016 to February 2019) were included. Multiple pregnancies, fetal abnormalities or births before 24+1 weeks were excluded. Clusters were randomised to immediate implementation of GAP, an antenatal care package aimed at improving detection of SGA as a means to reduce the rate of stillbirth, or to standard care. Randomisation by random permutation was stratified by time of study inclusion and cluster size. Data were obtained from hospital electronic records for 12 months prerandomisation, the washout period (interval between randomisation and data collection of outcomes), and the outcome period (last 6 months of the study). The primary outcome was ultrasound detection of SGA (estimated fetal weight <10th centile using customised centiles (intervention) or Hadlock centiles (standard care)) confirmed at birth (birthweight <10th centile by both customised and population centiles). Secondary outcomes were maternal and neonatal outcomes, including induction of labour, gestational age at delivery, mode of birth, neonatal morbidity, and stillbirth/perinatal mortality. A 2-stage cluster-summary statistical approach calculated the absolute difference (intervention minus standard care arm) adjusted using the prerandomisation estimate, maternal age, ethnicity, parity, and randomisation strata. Intervention arm clusters that made no attempt to implement GAP were excluded in modified intention to treat (mITT) analysis; full ITT was also reported. Process evaluation assessed implementation fidelity, reach, dose, acceptability, and feasibility. Seven clusters were randomised to GAP and 6 to standard care. Following exclusions, there were 11,096 births exposed to the intervention (5 clusters) and 13,810 exposed to standard care (6 clusters) during the outcome period (mITT analysis). Age, height, and weight were broadly similar between arms, but there were fewer women: of white ethnicity (56.2% versus 62.7%), and in the least deprived quintile of the Index of Multiple Deprivation (7.5% versus 16.5%) in the intervention arm during the outcome period. Antenatal detection of SGA was 25.9% in the intervention and 27.7% in the standard care arm (adjusted difference 2.2%, 95% confidence interval (CI) -6.4% to 10.7%; p = 0.62). Findings were consistent in full ITT analysis. Fidelity and dose of GAP implementation were variable, while a high proportion (88.7%) of women were reached. Use of routinely collected data is both a strength (cost-efficient) and a limitation (occurrence of missing data); the modest number of clusters limits our ability to study small effect sizes.

CONCLUSIONS

In this study, we observed no effect of GAP on antenatal detection of SGA compared to standard care. Given variable implementation observed, future studies should incorporate standardised implementation outcomes such as those reported here to determine generalisability of our findings.

TRIAL REGISTRATION

This trial is registered with the ISRCTN registry, ISRCTN67698474.

Does detection of fetal growth restriction improve neonatal outcomes?

AIM

Timely delivery of fetal growth restriction (FGR) is a balance between avoiding stillbirth and minimising prematurity. We sought to assess the neonatal outcomes for babies suspected of FGR, both true and false positives.

METHODS

This population cohort study examined all singleton births in Victoria, Australia from 2000 to 2017 (n = 1 231 415). Neonatal morbidities associated with neonatal intensive care unit (NICU) admission were assessed for babies born ≥32 weeks' with severe FGR (<3rd centile) and babies with birthweight ≥10th centile who were iatrogenically delivered for suspected FGR.

RESULTS

Babies with severe FGR iatrogenically delivered for suspected FGR were more likely to require NICU admission than babies with severe FGR who were not detected (3.0% vs. 1.1%, P < 0.001). After adjusting for potential confounders, the odds of NICU admission were increased (adjusted odds ratio (aOR) = 3.00, 95% confidence interval = 2.45-3.67; P < 0.001). Rates of NICU admission were also higher in ≥10th centile babies iatrogenically delivered for suspected FGR than for ≥10th centile babies who entered labour spontaneously (1.8% vs. 0.5%, P < 0.001). After adjustments, the odds of NICU admission were increased (aOR = 3.91, 95% confidence interval = 3.40-4.49; P < 0.001). NICU admissions were associated with morbidities related to iatrogenic prematurity.

CONCLUSIONS

Detection and planned delivery of FGR reduces stillbirth but may be associated with increased neonatal morbidity related to iatrogenic prematurity.

Ten-year experience of protocol-based management of small-for-gestational-age fetuses: perinatal outcome in late-pregnancy cases diagnosed after 32 weeks

OBJECTIVE

To report our 10-year experience of protocol-based management of small-for-gestational-age (SGA) fetuses, based on standardized clinical and Doppler criteria, in late-pregnancy cases.

METHODS

A retrospective cohort was constructed of consecutive singleton pregnancies referred for late-onset (> 32 weeks) SGA (defined as estimated fetal weight (EFW) < 10^th centile) that were classified as fetal growth restriction (FGR) or low-risk SGA, based on the severity of smallness (EFW < 3^rd centile) and the presence of Doppler abnormalities (uterine artery pulsatility index (UtA-PI) ≥ 95^th centile or cerebroplacental ratio (CPR) < 5^th centile). Low-risk SGA pregnancies were followed at 2-week intervals and delivered electively at 40 weeks. FGR pregnancies were followed at 1-week intervals, or more frequently if there were signs of fetal deterioration, and were delivered electively after 37 + 0 weeks' gestation. The occurrence of stillbirth and composite adverse outcome (CAO; defined as neonatal death, metabolic acidosis, need for endotracheal intubation or need for admission to the neonatal intensive care unit) was analyzed in low-risk SGA and FGR pregnancies.

RESULTS

A total of 1197 pregnancies with EFW < 10^th centile were identified and classified at diagnosis as low-risk SGA (n = 619; 51.7%) or FGR (n = 578; 48.3%). Of these, 160 were delivered before 37 weeks' gestation; for obstetric reasons in 93 (58.1%) cases, severe pre-eclampsia in 33 (20.6%), FGR with severe hypoxia in 47 (29.4%) and stillbirth in four (2.5%) (indications are non-exclusive). During follow-up, 52/574 (9.1%) low-risk SGA pregnancies were reclassified as FGR, whereas 22/463 (4.8%) FGR pregnancies were reclassified as low-risk SGA. Overall, there were no stillbirths in the low-risk SGA group and four in the FGR group, all of which occurred before 37 weeks. There were no instances of neonatal death in pregnancies delivered ≥ 37 weeks. The risk of CAO was higher in those meeting antenatal criteria for FGR at 37 weeks than in those classified as low-risk SGA (32/493 (6.5%) vs 15/544 (2.8%); odds ratio, 2.5 (95% CI, 1.3-4.6)). In FGR pregnancies, the adjusted odds ratio (95% CI) for CAO was 6.3 (1.8-21.1) in those with EFW < 3^rd centile, while it was 3.2 (1.5-6.8) and 4.2 (1.9-8.9) in those with UtA-PI ≥ 95^th centile and CPR < 5^th centile, respectively, as compared to FGR pregnancies without each of these criteria.

CONCLUSION

Protocol-based risk stratification with different management and monitoring schemes for late pregnancy with a suspected SGA baby, based on clinical and Doppler criteria, enables identification and tailored assessment of high-risk FGR, while allowing expectant management with safe perinatal outcome for low-risk SGA fetuses. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Detection of small for gestational age babies and perinatal outcomes following implementation of the Growth Assessment Protocol at a New Zealand tertiary facility: An observational intervention study

BACKGROUND

Timely detection of small for gestational age (SGA) fetuses is important for reducing severe perinatal morbidity and mortality, and better tools are needed to detect SGA in maternity care.

AIM

We evaluated the effect of the introduction of the Perinatal Institute's Growth Assessment Protocol (GAP) in the Counties Manukau Health region, South Auckland, New Zealand, on antenatal detection of SGA and maternal and perinatal outcomes.

MATERIALS AND METHODS

Uncontrolled before and after study in women booked under hospital community midwife care with a singleton, non-anomalous pregnancy. Antenatal detection of SGA (birthweight <10th customised centile) was compared pre-GAP (2012, N = 1105) and post-GAP (2017, N = 1082). Composite adverse neonatal outcome was defined as neonatal unit admission >48 h, five-minute Apgar score <7, and/or any ventilation. Analyses were adjusted for maternal age, body mass index, deprivation, smoking and ethnicity.

RESULTS

SGA rates were similar across epochs (13.8% vs 12.9%) but antenatal detection of SGA increased from 22.9% (35/153) to 57.9% (81/140) post-GAP (adjusted odds ratio (aOR) = 4.8, 95% CI 2.82-8.18). Rates of induction of labour and caesarean section increased between epochs but were similar in SGA, non-SGA, and detected and non-detected SGA subgroups. Among SGA babies, there was some evidence that antenatal detection of SGA may be associated with lower composite adverse neonatal outcome (detected SGA: aOR 0.44 95% CI 0.17-1.15; non-detected SGA: aOR = 1.81 95% CI 0.73-4.48; interaction P = 0.03). Pre-term birth did not appear to be influenced by GAP.

CONCLUSION

Implementation of GAP was associated with a nearly five-fold increase in SGA detection without increasing obstetric intervention for SGA.

The PLANES study: a protocol for a randomised controlled feasibility study of the placental growth factor (PlGF) blood test-informed care versus standard care alone for women with a small for gestational age fetus at or after 32 + 0 weeks' gestation

Background

Stillbirth remains a major concern across the globe and in some high-resource countries, such as the UK; efforts to reduce the rate have achieved only modest reductions. One third of stillborn babies are small for gestational age (SGA), and these pregnancies are also at risk of neonatal adverse outcomes and lifelong health problems, especially when delivered preterm. Current UK clinical guidance advocates regular monitoring and early term delivery of the SGA fetus; however, the most appropriate regimen for surveillance of these babies remains unclear and often leads to increased intervention for a large number of these women. This pilot trial will determine the feasibility of a large-scale trial refining the risk of adverse pregnancy outcome in SGA pregnancies using biomarkers of placental function sFlt-1/PlGF, identifying and intervening in only those deemed at highest risk of stillbirth.

Methods

PLANES is a randomised controlled feasibility study of women with an SGA fetus that will be conducted at two tertiary care hospitals in the UK. Once identified on ultrasound, women will be randomised into two groups in a 3:1 ratio in favour of sFlt-1/PlGF ratio led management vs standard care. Women with an SGA fetus and a normal sFlt-1/PlGF ratio will have a repeat ultrasound and sFlt-1/PlGF ratio every 2 weeks with planned birth delayed until 40 weeks. In those women with an SGA fetus and an abnormal sFlt-1/PlGF ratio, we will offer birth from 37 weeks or sooner if there are other concerning features on ultrasound. Women assigned to standard care will have an sFlt-1/PlGF ratio taken, but the results will be concealed from the clinical team, and the woman’s pregnancy will be managed as per the local NHS hospital policy. This integrated mixed method study will also involve a health economic analysis and a perspective work package exploring trial feasibility through interviews and questionnaires with participants, their partners, and clinicians.

Discussion

Our aim is to determine feasibility through the assessment of our ability to recruit and retain participants to the study. Results from this pilot study will inform the design of a future large randomised controlled trial that will be adequately powered for adverse pregnancy outcome. Such a study would provide the evidence needed to guide future management of the SGA fetus.

Trial registration

ISRCTN58254381. Registered on 4 July 2019

Application of new fetal growth standards in a multiethnic population

OBJECTIVES

Ultrasound assessment of fetal growth is essential to reduce adverse pregnancy outcomes. Intergrowth-21st developed international standards. Currently, we use in France chart based on Hadlock's formula. This study aims to evaluate, the impact of switching from national curves to IG-21 curves or a combination of IG-21 with Hadlock.

METHODS

The study population consisted of 3 697 singleton pregnancies with fetal biometry measured between 22 and 38 weeks of gestation. Z-scores were calculated for each biometry according to CFEF and IG-21. The estimated fetal weight and its Z-score were calculated using the Hadlock formula and IG-21 formula.

RESULTS

We observed 21% of head circumference, 9% of abdominal circumference and 7% of femoral length below the 10th centile with Intergrowth-21. Concerning estimated fetal weight, IG-21 classified 13.8% fetuses as SGA, IG-21/Hadlock 10.8% and CFEF 16.1%. Between 36 and 38 weeks of gestation, IG-21 classified more fetuses as SGA than IG-21/Hadlock and CFEF, respectively 18%, 14.1% and 13.3%.

CONCLUSION

The use of IG-21 or IG-21/Hadlock in the general population would lower the number of fetuses classified as SGA except for fetuses between 36 and 38 weeks. During this period, many decisions of induced early delivery or specific management are established to prevent adverse perinatal outcome. Those results must be supplemented by a comparison to newborns' weight.

Safety of misoprostol for near-term and term induction in small-for-gestational-age pregnancies compared to dinoprostone and primary cesarean section: results of a retrospective cohort study

OBJECTIVES

Small-for-gestational-age (SGA) pregnancy is a condition often leading to labor induction due to concerns about the possibility of an increased risk for fetal morbidity and mortality. In this retrospective cohort study, we try to evaluate the safety of oral misoprostol for labor induction in near-term and term pregnancies in SGA fetuses compared to dinoprostone as well as to planned primary cesarean section.

MATERIALS AND METHODS

Retrospective analysis of labor indution and primary cesarean section in SGA pregnancies 37 weeks and beyond in a tertiary care centre. In total, 284 consecutive patients with SGA fetuses were included. 80 recieved oral misoprostol, 85 dinoprostone as vaginal Gel and 119 were delivered by means of primary cesarean section. Primary endpoints were umbilical aterial pH and APGAR 5'. Secondary endpoints were APGAR 1' and 10', rates of relevant acidosis with a pH < 7.11 and depressed children, NICU admissions and vaginal operative deliveries as well as cesarean sections after labor induction.

RESULTS

No significant differences were found concerning the umbilical arterial pH. No significant differences were found concerning APGAR 5' after labor induction; however, APGAR 5' was significantly lower after primary cesarean section. Similar results were found concerning APGAR 1', 10-min APGAR values were not significantly different. Rates of relevant acidosis and depressed children did not differ; no significant differences were found concerning NICU admissions between all groups and vaginal operative deliveries and CS rates after labor induciton.

CONCLUSION

Oral misoprosol is a safe method for labor induction in SGA near-term and term pregnancies and, concerning the neonatal outcome, comparable with other methods of labor induction or primary CS. Our study showed no adverse neonatal outcomes related to the use of oral misoprostol.

Role of Doppler ultrasound at time of diagnosis of late-onset fetal growth restriction in predicting adverse perinatal outcome: prospective cohort study

OBJECTIVE

Pregnancies complicated by late-onset fetal growth restriction (FGR) are at increased risk of short- and long-term morbidities. Despite this, identification of cases at higher risk of adverse perinatal outcome, at the time of FGR diagnosis, is challenging. The aims of this study were to elucidate the strength of association between fetoplacental Doppler indices at the time of diagnosis of late-onset FGR and adverse perinatal outcome, and to determine their predictive accuracy.

METHODS

This was a prospective study of consecutive singleton pregnancies complicated by late-onset FGR. Late-onset FGR was defined as estimated fetal weight (EFW) or abdominal circumference (AC) < 3^rd centile, or EFW or AC < 10^th centile and umbilical artery (UA) pulsatility index (PI) > 95^th centile or cerebroplacental ratio (CPR) < 5^th centile, diagnosed after 32 weeks. EFW, uterine artery PI, UA-PI, fetal middle cerebral artery (MCA) PI, CPR and umbilical vein blood flow normalized for fetal abdominal circumference (UVBF/AC) were recorded at the time of the diagnosis of FGR. Doppler variables were expressed as Z-scores for gestational age. Composite adverse perinatal outcome was defined as the occurrence of at least one of emergency Cesarean section for fetal distress, 5-min Apgar score < 7, umbilical artery pH < 7.10 and neonatal admission to the special care unit. Logistic regression analysis was used to elucidate the strength of association between different ultrasound parameters and composite adverse perinatal outcome, and receiver-operating-characteristics (ROC)-curve analysis was used to determine their predictive accuracy.

RESULTS

In total, 243 consecutive singleton pregnancies complicated by late-onset FGR were included. Composite adverse perinatal outcome occurred in 32.5% (95% CI, 26.7-38.8%) of cases. In pregnancies with composite adverse perinatal outcome, compared with those without, mean uterine artery PI Z-score (2.23 ± 1.34 vs 1.88 ± 0.89, P = 0.02) was higher, while Z-scores of UVBF/AC (-1.93 ± 0.88 vs -0.89 ± 0.94, P ≤ 0.0001), MCA-PI (-1.56 ± 0.93 vs -1.22 ± 0.84, P = 0.004) and CPR (-1.89 ± 1.12 vs -1.44 ± 1.02, P = 0.002) were lower. On multivariable logistic regression analysis, Z-scores of mean uterine artery PI (P = 0.04), CPR (P = 0.002) and UVBF/AC (P = 0.001) were associated independently with composite adverse perinatal outcome. UVBF/AC Z-score had an area under the ROC curve (AUC) of 0.723 (95% CI, 0.64-0.80) for composite adverse perinatal outcome, demonstrating better accuracy than that of mean uterine artery PI Z-score (AUC, 0.593; 95% CI, 0.50-0.69) and CPR Z-score (AUC, 0.615; 95% CI, 0.52-0.71). A multiparametric prediction model including Z-scores of MCA-PI, uterine artery PI and UVBF/AC had an AUC of 0.745 (95% CI, 0.66-0.83) for the prediction of composite adverse perinatal outcome.

CONCLUSION

While CPR and uterine artery PI assessed at the time of diagnosis are associated independently with composite adverse perinatal outcome in pregnancies complicated by late-onset FGR, their diagnostic performance for composite adverse perinatal outcome is low. UVBF/AC showed better accuracy for prediction of composite adverse perinatal outcome, although its usefulness in clinical practice as a standalone predictor of adverse pregnancy outcome requires further research. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Third-trimester uterine artery Doppler for prediction of adverse outcome in late small-for-gestational-age fetuses: systematic review and meta-analysis

OBJECTIVE

To investigate the predictive ability for adverse perinatal outcome of abnormal third-trimester uterine artery Doppler in late small-for-gestational-age (SGA) fetuses.

METHODS

A systematic search was performed to identify relevant observational studies and randomized controlled trials evaluating the performance of abnormal third-trimester uterine artery Doppler for the prediction of adverse perinatal outcome in suspected SGA fetuses and SGA neonates. Abnormal uterine artery Doppler was defined as uterine artery pulsatility index > 95^th percentile or ≥ 2 SD above the mean, or bilateral uterine artery notching. Hierarchical summary receiver-operating-characteristics (ROC) curves were constructed using random-effects modeling. Bayesian analysis was used to calculate the posterior probability of adverse perinatal outcome following an abnormal or normal uterine artery Doppler assessment.

RESULTS

Seventeen observational studies (including 7552 fetuses either diagnosed with suspected SGA (n = 3461) or later diagnosed as a SGA neonate (n = 4091)) met the inclusion criteria; no randomized-controlled trials met the inclusion criteria. Summary ROC curves showed that, among suspected SGA fetuses, the best predictive accuracy of abnormal third-trimester uterine artery Doppler was for perinatal mortality and the worst was for composite adverse perinatal outcome, with areas under the summary ROC curves of 0.90 and 0.66, respectively. The corresponding positive and negative likelihood ratios were 16.5 and 0.6 for perinatal mortality and 2.82 and 0.65 for composite adverse perinatal outcome, respectively. Following an abnormal vs normal uterine artery Doppler assessment, the posterior risks for composite adverse perinatal outcome, admission to the neonatal intensive care unit, Cesarean section for intrapartum fetal compromise, 5-min Apgar score < 7, neonatal acidosis and perinatal death were: 52.3% vs 20.2%, 48.6% vs 18.7%, 23.1% vs 15.2%, 3.59% vs 1.32%, 9.15% vs 5.12% and 31.4% vs 1.64%, respectively.

CONCLUSION

Abnormal uterine artery Doppler in the third trimester appears to be moderately useful in predicting perinatal death in pregnancies with suspected SGA. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Longitudinal change in cerebroplacental ratio in small-for-gestational-age fetuses and risk of stillbirth

OBJECTIVE

To investigate whether assessment of longitudinal change in Doppler variables in small-for-gestational-age (SGA) fetuses improves the prediction of those at risk of stillbirth.

METHODS

This was a longitudinal study of two cohorts of singleton pregnancies, which included SGA and appropriate-for-gestational-age (AGA) fetuses, respectively. The inclusion criteria for the SGA cohort were singleton pregnancy at ≥ 20 weeks' gestation, classified as SGA (estimated fetal weight < 10^th centile). The AGA cohort consisted of singleton pregnancies deemed at high risk of being SGA, which were followed up longitudinally but remained AGA. Fetal middle cerebral artery (MCA) pulsatility index (PI) and umbilical artery (UA)-PI were measured longitudinally and cerebroplacental ratio (CPR) was calculated, and values were converted to multiples of the median. The last two measurements prior to delivery were included in the analysis. Longitudinal models for Doppler variables were developed using linear-mixed models and their accuracy in the prediction of stillbirth was tested using generalized linear models. A Bayesian framework was employed to compare the accuracy of longitudinal and standard (last-scan measurement) models.

RESULTS

In total, 1549 AGA and 941 SGA pregnancies were included in the analysis. There were 30 (3.2%) and no stillbirth cases in the SGA and AGA groups, respectively. Change in MCA-PI, UA-PI and CPR with advancing gestation was significantly different between liveborn AGA and SGA fetuses, with a less pronounced difference with advancing gestation. Using the last measurement, the best models for the prediction of stillbirth in SGA pregnancies were those based on CPR (accuracy, 75.0%; 95% CI, 72.6-77.2%) and UA-PI (accuracy, 71.0%; 95% CI, 68.6-73.4%). The posterior probability of the standard CPR model having a higher accuracy compared with the UA-PI model was 97.2% (magnitude of change (MC), 3.9%; 95% credible interval (CrI), 0.5-7.3%). The accuracies of the standard, compared with the longitudinal, models for UA-PI (71.0% vs 72.8%), MCA-PI (64.6% vs 63.8%) and CPR (75.0% vs 74.9%) in the prediction of stillbirth were not significantly different. The posterior probabilities for improvement in accuracy using longitudinal, compared with standard, assessment were 50.1% (MC, < 0.1%; 95% CrI, -3.3 to 3.3%), 35.2% (MC, -0.1%; 95% CrI, -4.5 to 2.8%) and 82.2% (MC, 1.9%; 95% CrI, -1.5 to 5.3%) for CPR, MCA-PI and UA-PI models, respectively. Therefore, change in Doppler parameters did not improve the accuracy of the prediction of stillbirth, compared with that of the last-scan measurement.

CONCLUSION

Longitudinal assessment of Doppler parameters was not useful in improving the detection of stillbirth in SGA pregnancies, as compared with a single-point assessment. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Clinical significance of cerebroplacental ratio

PURPOSE OF REVIEW

Two-thirds of the pregnancies complicated by stillbirth demonstrate growth restriction. Identification of the foetus at risk of growth restriction is essential to reduce the risk of stillbirth. The aim of this review is to critically appraise the current evidence regarding clinical utility of cerebroplacental ratio (CPR) in antenatal surveillance.

RECENT FINDINGS

The CPR has emerged as an assessment tool for foetuses at increased risk of growth disorders. CPR is a better predictor of adverse events compared with middle-cerebral artery or umbilical artery Doppler alone. The predictive value of CPR for adverse perinatal outcomes is better for suspected small-for-gestational age foetuses compared with appropriate-for-gestational age (AGA) foetuses. CPR could be useful for the risk stratification of small-for-gestational age foetuses to determine the timing of delivery and also to calculate the risk of intrapartum compromise or prolonged admission to the neonatal care unit. Although there are many proposed cut-offs for an abnormal CPR value, evidence is currently lacking to suggest the use of one cut-off over another. CPR appears to be associated with increased risk of intrapartum foetal compromise, abnormal growth velocity, and lower birthweight in AGA foetuses as well. Moreover, birthweight differences are better explained with CPR compared to other factors such as ethnicity. However, the role of CPR in predicting adverse perinatal outcomes such as acidosis or low Apgar scores in AGA foetuses is yet to be determined.

SUMMARY

CPR appears to be a useful surrogate of suboptimal foetal growth and intrauterine hypoxia and it is associated with a variety of perinatal adverse events.

Is portable foetal electrocardiogram monitor feasible for foetal heart rate monitoring of small for gestational age foetuses in the home environment

Small-for-gestational-age (SGA) foetuses are at greater risk of complications than normal foetuses. Studies have demonstrated that foetal electrocardiogram (ECG) device (Monica-AN24) can be employed for monitoring foetal heart rate (FHR). However, its reliability and acceptability has not been assessed in SGA foetuses. This study was aimed at: (a) determining the acceptability of wearing the device more than once, (b) investigating the reliability of acquiring successful FHR data at different gestation. Patients with singleton non-anomalous foetus >24 weeks gestation and an estimated foetal weight below tenth percentile were recruited. Thirty-five women wore the device once. Twenty-four of these wore second time (68.6%). Overall, success-rate of FHR signals was 48.6% and increased to 68.8% beyond 34 weeks gestation. Foetal ECG is a promising method for monitoring SGA foetus >34 weeks gestation. Compared to day recordings, foetal signals were more reliable at night. Further studies are required before its clinical utility can be ascertained. IMPACT STATEMENT What is already known on this subject? Pregnancies that are affected by small-for-gestational-age (SGA) foetus pose a major public health problem and are associated with increased perinatal morbidity and mortality. There is no consensus on the optimal timing of delivery. Current methods employed for monitoring SGA foetuses include ultrasound scans for foetal-biometry and Doppler assessments. However, they provide a snapshot of information on foetal well-being, restrict patient mobility and cannot be employed over long-time periods. It is plausible that ambulatory foetal-ECG device that enable monitoring over a longer time period may better inform decisions about the timing of delivery. What do the results of this study add? Trans-abdominal foetal-ECG is a promising method of monitoring SGA foetus in the home setting with a success rate of acquiring reliable foetal heart rate (FHR) data over 90% at night time. What are the implications of these findings for clinical practice and/or further research? Overall, the study approved the concept of long-term home monitoring and has highlighted the facilitators and barriers to wearing the monitor in clinical care. These observations can be used to undertake robust research to assess the use of foetal-ECG monitor singly or in conjunction with current monitoring techniques for optimal foetal surveillance.

Using fetal abdominal circumference growth velocity in the prediction of adverse outcome in near-term small-for-gestational-age fetuses

OBJECTIVE

To investigate whether abdominal circumference growth velocity (ACGV) improves the prediction of perinatal outcome in small-for-gestational-age (SGA) fetuses beyond that afforded by estimated fetal weight (EFW) and cerebroplacental ratio (CPR).

METHODS

A cohort of 235 singleton SGA fetuses at 36-38 weeks' gestation was examined. ACGV, EFW and CPR centiles were calculated. ACGV centile was determined using data from a large database of 19-21- and 36-38-week scans in an unselected population. Binary variables of ACGV < 10^th , EFW < 3^rd and CPR < 5^th centiles were defined as abnormal. Two composite adverse outcomes (CAO) were explored: CAO-1 defined as at least one of umbilical artery pH < 7.10, 5-min Apgar score < 7 or neonatal unit admission, and CAO-2 that included in addition hypoglycemia, intrapartum fetal distress and perinatal death. Univariate and multivariate logistic regression analyses were performed to analyze the relationship between the three risk factors and their predictive value for CAO. The change in screening performance afforded by adding ACGV to EFW and CPR was assessed and receiver-operating characteristics (ROC) curves were calculated.

RESULTS

ACGV < 10^th centile was an independent risk factor for CAO. The sensitivity, specificity, positive and negative likelihood ratios of a predictive model based on EFW < 3^rd centile and CPR < 5^th centile were, respectively, 51%, 70%, 1.71 and 0.69 for CAO-1 and 41%, 70%, 1.39 and 0.83 for CAO-2. After addition of ACGV < 10^th centile to the model, the respective values were 82%, 46%, 1.54 and 0.38 for CAO-1 and 71%, 47%, 1.34 and 0.62 for CAO-2. Using continuous variables, the areas under the ROC curves improved marginally from 0.669 (95% CI, 0.604-0.729) to 0.741 (95% CI, 0.677-0.798) for CAO-1 and from 0.646 (95% CI, 0.580-0.707) to 0.700 (95% CI, 0.633-0.759) for CAO-2 after addition of ACGV to the model.

CONCLUSIONS

ACGV is a risk factor for adverse neonatal outcome that is independent of EFW and of CPR, although any improvement in the prediction of adverse outcome is not statistically significant. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.