How to monitor pregnancies complicated by fetal growth restriction and delivery before 32 weeks: post-hoc analysis of TRUFFLE study

Pentaerythrityl tetranitrate improves the outcome of children born to mothers with compromised uterine perfusion-12-months follow-up and safety data of the double-blind randomized PETN trial

BACKGROUND

This is a follow-up study to the pentaerythrityl tetranitrate randomized controlled multicenter trial that reports neonatal outcome data of newborns admitted to neonatal intensive care units and outcome data of the offspring at 12 months of age.

OBJECTIVE

We present data on adverse events reported during the study to document the safety of pentaerythrityl tetranitrate treatment during pregnancy. To further evaluate the effects of pentaerythrityl tetranitrate on neonatal and long-term outcomes, we present follow up data from of 240 children at 12 months of age, including information on height, weight, head circumference, developmental milestones, and the presence of chronic disease and of 144 newborns admitted to the neonatal intensive care unit during the trial.

STUDY DESIGN

The pentaerythrityl tetranitrate trial was a randomized, double-blind, placebo-controlled study designed to assess the efficacy and safety of the nitric oxide-donor pentaerythrityl tetranitrate in the prevention of fetal growth restriction and perinatal death in pregnancies complicated by abnormal placental perfusion.

RESULTS

Results at 12 months demonstrated that significantly more children were age appropriately developed without impairments in the pentaerythrityl tetranitrate group (P=.018). In addition, the presence of chronic disease was lower in the pentaerythrityl tetranitrate group (P=.041). Outcome data of the 144 newborns admitted to the neonatal intensive care unit did not reveal differences between the treatment and placebo groups. There were no differences in the number or nature of reported adverse events between the study groups.

CONCLUSION

The analysis shows that study children born in the pentaerythrityl tetranitrate cohort have a clear advantage compared with the placebo group at the age of 12 months, as evidenced by the increased incidence of normal development without the presence of chronic disease. Although safety has been proven, further follow-up studies are necessary to justify pentaerythrityl tetranitrate treatment during pregnancies complicated by impaired uterine perfusion.

Assessing the external validity and clinical relevance of umbilical doppler resistance index references in daily practice

OBJECTIVE

To assess the external validity and clinical relevance of current references for umbilical artery resistance index (UA RI) in daily practice.

METHODS

Retrospective cross-sectional single center study including all UA RI measurements between 22 and 40 gestational weeks (GW) from distinct patients between 2014 and 2022. Patients with normal pregnancies and normal neonatal outcomes that had an UA RI measurement between 2014 and 2019 were used to calculate reference ranges. The established reference for the 95th centile was compared to two current references. The clinical relevance of the established reference was tested by comparing neonatal outcomes according to the 95th percentile among the consecutive distinct patients between 2020 and 2022.

RESULTS

Among the 13342 consecutive distinct patients with a singleton pregnancy that had an UA RI measurement between 22 and 40 GW between 2014 and 2022, 5298 patients were included to establish the reference ranges, and 3634 patients to validate these ranges. For each gestational age, the established references were similar to current references. Using the established references, the proportion of patients presenting an UA RI>95th percentile among the patients with normal pregnancies in the validation population was comparable to the proportion when using the two current references. Among the validation population, 268 patients (7.4 %) (95%CI[6.5-8.2]) presented an UA RI ≥ 95th percentile. Of these 268 patients, 67.9% had a SGA newborn (versus 19.2%, p<0.001) and 59% a preterm birth (versus 13.9%, p<0.001).

CONCLUSIONS

The reference range obtained from daily practice is clinically relevant and similar to current references.

Comparison of phase rectified signal averaging and short term variation in predicting perinatal outcome in early onset fetal growth restriction

OBJECTIVES

To compare short term variation (STV) and phase rectified signal averaging (PRSA) and their association with fetal outcome in early onset fetal growth restriction (FGR).

METHODS

Data were used from a retrospective cohort study of women who were admitted for FGR and/or pre-eclampsia and who were delivered by pre-labor Cesarean section or had a fetal death before 32 weeks' gestation. Computerized cardiotocography (cCTG) registrations of the 5 days before delivery or fetal death were used for calculation of STV and PRSA. PRSA was expressed as the average acceleration capacity (AAC) and average deceleration capacity (ADC). FHR decelerations were classified visually as absent, 1-2 per hour or recurrent. Abnormality of STV and of PRSA was either analyzed as a single parameter or in combination with recurrent decelerations. Endpoints were defined as composite adverse condition at birth consisting of fetal death, low Apgar score, low umbilical pH, the need for resuscitation after birth and as major neonatal morbidity or neonatal death.

RESULTS

Included were 367 pregnancies of which 20 resulted in fetal death. An abnormal cCTG with either recurrent decelerations and/or low STV or recurrent decelerations and/or low PRSA were similarly associated with composite adverse condition at birth (n=99), but neither with major neonatal morbidity.

CONCLUSIONS

PRSA and STV have similar efficacy for measuring fetal heart rate variation in early onset FGR. An increased risk of a composite adverse condition at birth is indicated by a low value of either parameter and/or the presence of recurrent decelerations.

Association of fetal heart rate short term variability pattern during term labor with neonatal morbidity and small for gestational age status

OBJECTIVE

To assess the association of fetal heart rate short-term variability (STV) pattern during term labor with both neonatal composite morbidity (cord blood pH ≤ 7.10 and/or neonatal intensive care unit admission and/or Apgar score at 5 min <7) and small for gestational age (SGA) status.

STUDY DESIGN

Retrospective cohort in a single academic institution between January 2016 and December 2018. A total of 1896 women that delivered a singleton during labor in cephalic presentation after 37 weeks of gestation were included (948 women with SGA neonates and 948 women with appropriate weight for gestational age (AGA) neonates that were matched to women with SGA neonates based on maternal age, parity, induction of labor, gestational diabetes, gestational age at delivery and a history of one cesarean section using propensity score matching). STV was compared at labor onset (cervical dilation ≤ 4 cm), in the first stage of labor (cervical dilation = 6 cm) and in the second stage of labor (cervical dilation = 10 cm). A generalized linear mixed model was used to assess the association between SGA status, neonatal composite morbidity and STV.

RESULTS

After adjustment for maternal origin, term, gestational diabetes, labor length, SGA status was not associated with any change in STV during labor (mean adjusted STV: -0.20 ms, 95 %CI[-0.58-0.17], p = 0.284 at labor onset, 0.29 ms, 95 %CI[-0.1- 0.68], p = 0.155, in the first stage of labor and 0.36 ms, 95 %CI[-0.02-0.74], p = 0.065 in the second stage of labor). In case of neonatal composite morbidity mean adjusted STV was lower in the first stage of labor (mean adjusted STV: -1.29 ms, 95 %CI[-2.1 - -0.43], p = 0.003) and in the second stage of labor (mean adjusted STV: -1.15 ms, 95 %CI[-1.96 - -0.34], p = 0.005). The results were similar with the addition of delivery mode and meconium-stained amniotic fluid in the model or non-reassuring fetal heart rate and meconium-stained amniotic fluid.

CONCLUSIONS

This work suggests that STV decrease during term labor is associated with fetal well-being, independently of fetal weight. This suggests that further prospective studies should consider the evaluation of this parameter in the prediction of neonatal compromise.

Timing of antenatal steroid administration for imminent preterm birth: results of a prospective observational study in Germany

PURPOSE

To evaluate the timing of antenatal steroid administration and associated medical interventions in women with imminent preterm birth.

METHODS

We performed a prospective observational study at a single tertiary center in Germany from September 2018 to August 2019. We included pregnant women who received antenatal steroids for imminent preterm birth and evaluated the interval from administration to birth. 120 women with antenatal steroid application were included into our analysis. Descriptive statistics were performed to analyze factors influencing the timing of antenatal steroids and to evaluate additional medical interventions which women with imminent preterm birth experience.

RESULTS

Of the 120 women included into our study, 35.8% gave birth before 34/0 weeks and 64.2% before 37/0 weeks of gestation. Only 25/120 women (20.8%) delivered within the optimal time window of 1-7 days after antenatal steroid application. 5/120 women (4.2%) only received one dose of antenatal steroids before birth and 3/120 (2.5%) gave birth within 8 to 14 days after antenatal steroids. Most women gave birth more than 14 days after steroid application (72.5%, 87/120). Women with preeclampsia (60%), PPROM (31%), and FGR (30%) had the highest rates of delivery within the optimal time window. Women of all timing groups received additional interventions and medications like antibiotics, tocolytics, or anticoagulation.

CONCLUSION

Our observational data indicate that most pregnant women do not give birth within 7 days after the administration of antenatal steroids. The timing was best for preterm birth due to preeclampsia, PPROM, and FGR. Especially for women with symptoms of preterm labor and bleeding placenta previa, antenatal steroids should be indicated more restrictively to improve neonatal outcome and reduce untimely and unnecessary interventions.

Altered Transmission of Cardiac Cycles to Ductus Venosus Blood Flow in Fetal Growth Restriction: Why Ductus Venosus Reflects Fetal Circulatory Changes More Precisely

We aimed to investigate the relation between the time intervals of the flow velocity waveform of ductus venosus (DV-FVW) and cardiac cycles. We defined Delta A as the difference in the time measurements between DV-FVW and cardiac cycles on the assumption that the second peak of ductus venosus (D-wave) starts simultaneously with the opening of the mitral valve (MV). As well, we defined Delta B as the difference of the time measurements between DV-FVW and cardiac cycles on the assumption that the D-wave starts simultaneously with the closure of the aortic valve (AV). We then compared Delta A and Delta B in the control and fetal growth restriction (FGR) groups. In the control group of healthy fetuses, Delta A was strikingly shorter than Delta B. On the other hand, in all FGR cases, no difference was observed. The acceleration of the D-wave is suggested to be generated by the opening of the MV under normal fetal hemodynamics, whereas it precedes the opening of the MV in FGR. Our results indicate that the time interval of DV analysis might be a more informative parameter than the analysis of cardiac cycles.

The role of the fetal biophysical profile in the management of fetal growth restriction

Growth-restricted fetuses are at risk of hypoxemia, acidemia, and stillbirth because of progressive placental dysfunction. Current fetal well-being, neonatal risks following delivery, and the anticipated rate of fetal deterioration are the major management considerations in fetal growth restriction. Surveillance has to quantify the fetal risks accurately to determine the delivery threshold and identify the testing frequency most likely to capture future deterioration and prevent stillbirth. From the second trimester onward, the biophysical profile score correlates over 90% with the current fetal pH, and a normal score predicts a pH >7.25 with a 100% positive predictive value; an abnormal score on the other hand predicts current fetal acidemia with similar certainty. Between 30% and 70% of growth-restricted fetuses with a nonreactive heart rate require biophysical profile scoring to verify fetal well-being, and an abnormal score in 8% to 27% identifies the need for delivery, which is not suspected by Doppler findings. Future fetal well-being is not predicted by the biophysical profile score, which emphasizes the importance of umbilical artery Doppler and amniotic fluid volume to determine surveillance frequency. Studies with integrated surveillance strategies that combine frequent heart rate monitoring with biophysical profile scoring and Doppler report better outcomes and stillbirth rates of between 0% and 4%, compared with those between 8% and 11% with empirically determined surveillance frequency. The variations in clinical behavior and management challenges across gestational age are better addressed when biophysical profile scoring is integrated into the surveillance of fetal growth restriction. This review aims to provide guidance on biophysical profile scoring in the in- and outpatient management of fetal growth restriction.

Testing the assumptions of customized intrauterine growth charts using national birth studies

INTRODUCTION

Customized intrauterine growth charts are widely used for growth monitoring and research. They are based on three assumptions: (1) estimated fetal weight (EFW) has a normal distribution with a constant coefficient of variation at all gestational ages; (2) Hadlock's growth curve accurately describes the relation between EFW and gestational ages; (3) associations between EFW and the fetal and maternal characteristics included in the customization model (fetal sex, pre-pregnancy weight, height, parity) are proportional throughout pregnancy. The aim of this study was to test whether these underlying assumptions are verified.

MATERIAL AND METHODS

Data came from (1) the French Longitudinal Study of Children (ELFE) cohort, which recruited births after 32 weeks' gestation in 349 maternity hospitals in France in 2011, and (2) the National Perinatal Survey, which included births from all French maternity hospitals in 2016. The study population included, respectively, 6 920 and 8 969 singleton non-malformed term live births with data on customization characteristics and EFW. We computed the coefficient of variation by gestational age and then modeled the association of gestational age, maternal and fetal characteristics with EFW at the second and third trimester ultrasound and with birthweight using linear regression. To assess the proportionality of the impact of maternal and fetal characteristics, we computed the percent change in weight associated with these characteristics at these three time points.

RESULTS

The coefficient of variation was close to 12% at each gestational age, but EFW was not normally distributed, leading to small but systematic underestimation of fetuses under the 10th percentile. Weights representing the 50th and 10th percentiles based on Hadlock's growth trajectory were lower than observed or predicted weights. Most characteristics more strongly impacted weight at birth than during pregnancy. In the French Longitudinal study of Children (ELFE) cohort, boys were 1.8% (95% confidence interval [CI] 1.3-2.4) heavier than girls in the third trimester, whereas this percentage was 4.6% (95% CI 4.0-5.2) at birth. In the National Perinatal Survey, these percentages were 2.3% (95% CI 1.8-2.8) and 4.3% (95% CI 3.8-4.8).

CONCLUSIONS

These results from two independent sources revealed discrepancies between routine clinical EFW data used for growth monitoring and the customized growth model's assumptions.

Time interval analysis of ductus venosus and cardiac cycles in relation with umbilical artery pH at birth in fetal growth restriction

Background

The aims of this study were to evaluate the time intervals of flow velocity waveforms (FVW) of ductus venosus (DV) and cardiac cycles, as well as the pulsatility index of DV-FVW (DV-PI), in correlation with umbilical artery (UA) pH at birth in fetal growth restriction (FGR) complicated with placental insufficiency.

Methods

Data were retrospectively retrieved from pregnancies complicated by FGR. FGR was defined as an estimated fetal weight below − 2.0 S.D. with an elevated UA-PI. Time interval assessments of DV-FVW were as follows: the duration of systolic wave was divided by the duration of diastolic wave and defined as DV-S/D. We also measured the following time intervals of ventricular inflow through tricuspid valve (TV) and mitral valve (MV): (iii), from the second peak of ventricular inflow caused by atrial contraction (A-wave) to the opening of atrio-ventricular valves and: (iv), from the opening of atrio-ventricular valves to the peak of A-wave. (iii)/(iv) was expressed as TV-S/D and MV-S/D, for TV and MV, respectively. The time interval data were transformed into z-scores.

Results

Thirty-one FGR fetuses were included in this study. Both DV-PI and DV-S/D showed significant correlation with UA-pH (r = − 0.677, p = < 0.001 and r = 0.489, p = 0.005 for DV-PI and z-score of DV-S/D, respectively) and more significances were observed in FGR ≤ 28 + 6 gestational weeks (r = − 0.819, p < 0.001 and r = 0.726, p = 0.005, for DV-PI and z-score of DV-S/D, respectively) than in FGR > 28 + 6 gestational weeks (r = − 0.634, p = 0.007 and r = 0.635, p = 0.020, for DV-PI and z-score of DV-S/D, respectively). On the other hand, TV-S/D and MV-S/D showed no significant correlation with UA-pH, although these z-scores indicated significant decreases compared with normal references.

Conclusions

Time interval analysis of DV-FVW might be a valuable parameter, as well as DV-PI, for the antenatal prediction of fetal acidemia in the management of FGR fetuses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04115-7.

Minimum evidence-based care in intrauterine growth-restricted fetuses and neonatal prognosis

BACKGROUND

Introduction: There is clear evidence that fetuses with intrauterine growth restriction (IUGR) do not receive the minimum evidence-based care during their antenatal management.

OBJECTIVE

Considering that optimal management of IUGR may reduce neonatal morbi-mortality in IUGR, the objective of the present study was to evaluate the impact of antenatal management of IUGR according to the recommendations of the French college of gynecologists and obstetricians (CNGOF) on the neonatal prognosis of IUGR fetuses.

STUDY DESIGN

From a historical cohort of 31,052 children, born at the Femme Mère Enfant hospital (Lyon, France) between January 1, 2011 and December 31, 2017, we selected the population of IUGR fetuses. The minimum evidence-based care (MEC) in the antenatal management of fetuses with IUGR was defined according to the CNGOF recommendations and neonatal prognosis of early and late IUGR fetuses were assessed based on the whether or not they received MEC. The neonatal prognosis was defined according to a composite criterion that included neonatal morbidity and mortality.

RESULTS

A total of 1020 fetuses with IUGR were studied. The application of MEC showed an improvement in the neonatal prognosis of early-onset IUGR (p = 0.003), and an improvement in the neonatal prognosis of IUGR born before 32 weeks (p = 0.030). Multivariate analysis confirmed the results showing an increase in neonatal morbi-mortality in early-onset IUGR in the absence of MEC with OR 1.79 (95% CI 1.01-3.19).

CONCLUSION

Diagnosed IUGR with MEC had a better neonatal prognosis when born before 32 weeks. Regardless of the birth term, MEC improved the neonatal prognosis of fetuses with early IUGR. Improvement in the rate of MEC during antenatal management has a significant impact on neonatal prognosis.

Evaluation and Management of Suspected Fetal Growth Restriction

Impaired fetal growth owing to placental insufficiency is a major contributor to adverse perinatal outcomes. No intervention is available that improves outcomes by changing the pathophysiologic process. Monitoring in early-onset fetal growth restriction (FGR) focuses on optimizing the timing of iatrogenic preterm delivery using cardiotocography and Doppler ultrasound. In late-onset FGR, identifying the fetus at risk for immediate hypoxia and who benefits from expedited delivery is challenging. It is likely that studies in the next decade will provide evidence how to best integrate different monitoring variables and other prognosticators in risk models that are aimed to optimize individual treatment strategies.

International versus national growth charts for identifying small and large-for-gestational age newborns: A population-based study in 15 European countries

BACKGROUND

To inform the on-going debate about the use of universal prescriptive versus national intrauterine growth charts, we compared perinatal mortality for small and large-for-gestational-age (SGA/LGA) infants according to international and national charts in Europe.

METHODS

We classified singleton births from 33 to 42 weeks of gestation in 2010 and 2014 from 15 countries (N = 1,475,457) as SGA (birthweight <10th percentile) and LGA (>90th percentile) using the international Intergrowth-21st newborn standards and national charts based on the customised charts methodology. We computed sex-adjusted odds ratios (aOR) for stillbirth, neonatal and extended perinatal mortality by this classification using multilevel models.

FINDINGS

SGA and LGA prevalence using national charts were near 10% in all countries, but varied according to international charts with a north to south gradient (3.0% to 10.1% and 24.9% to 8.0%, respectively). Compared with appropriate for gestational age (AGA) infants by both charts, risk of perinatal mortality was increased for SGA by both charts (aOR[95% confidence interval (CI)]=6.1 [5.6-6.7]) and infants reclassified by international charts from SGA to AGA (2.7 [2.3-3.1]), but decreased for those reclassified from AGA to LGA (0.6 [0.4-0.7]). Results were similar for stillbirth and neonatal death.

INTERPRETATION

Using international instead of national charts in Europe could lead to growth restricted infants being reclassified as having normal growth, while infants with low risks of mortality could be reclassified as having excessive growth.

FUNDING

InfAct Joint Action, CHAFEA Grant n°801,553 and EU/EFPIA Innovative Medicines Initiative 2 Joint Undertaking ConcePTION grant n°821,520. AH received a PhD grant from EHESP.

Monitoring, Delivery and Outcome in Early Onset Fetal Growth Restriction

Early fetal growth restriction (FGR) remains a challenging entity associated with an increased risk of perinatal morbidity and mortality as well as maternal complications. Significant variations in clinical practice have historically characterized the management of early FGR fetuses. Nevertheless, insights into diagnosis and management options have more recently emerged. The aim of this review is to summarize the available evidence on monitoring, delivery and outcome in early-onset FGR.

A review of fetal cardiac monitoring, with a focus on low- and middle-income countries

There is limited evidence regarding the utility of fetal monitoring during pregnancy, particularly during labor and delivery. Developed countries rely on consensus 'best practices' of obstetrics and gynecology professional societies to guide their protocols and policies. Protocols are often driven by the desire to be as safe as possible and avoid litigation, regardless of the cost of downstream treatment. In high-resource settings, there may be a justification for this approach. In low-resource settings, in particular, interventions can be costly and lead to adverse outcomes in subsequent pregnancies. Therefore, it is essential to consider the evidence and cost of different fetal monitoring approaches, particularly in the context of treatment and care in low-to-middle income countries. This article reviews the standard methods used for fetal monitoring, with particular emphasis on fetal cardiac assessment, which is a reliable indicator of fetal well-being. An overview of fetal monitoring practices in low-to-middle income counties, including perinatal care access challenges, is also presented. Finally, an overview of how mobile technology may help reduce barriers to perinatal care access in low-resource settings is provided.

Prognostic value of diffusion-weighted magnetic resonance imaging of brain in fetal growth restriction: results of prospective multicenter study

OBJECTIVE

To measure prospectively apparent diffusion coefficient (ADC) values between 28 and 32 weeks of gestation in different cerebral territories of fetuses with estimated fetal weight (EFW) ≤ 5^th centile, and analyze their association with adverse perinatal outcome.

METHODS

This was a prospective study involving six tertiary-level perinatal centers. In the period 22 November 2016 to 11 September 2017, we included singleton, small-for-gestational-age (SGA) fetuses with EFW ≤ 5^th percentile, between 28 and 32 weeks of gestation, regardless of the umbilical artery Doppler and maternal uterine artery Doppler findings. A fetal magnetic resonance imaging (MRI) examination with diffusion-weighted sequences (DWI) was performed within 14 days following inclusion and before 32 weeks. ADC values were calculated in the frontal and occipital white matter, basal ganglia and cerebellar hemispheres. An ultrasound examination was performed within 1 week prior to the MRI examination. The primary outcome was a composite measure of adverse perinatal outcome, defined as any of the following: perinatal death; admission to neonatal intensive care unit with mechanical ventilation > 48 h; necrotizing enterocolitis; Grade III-IV intraventricular hemorrhage; periventricular leukomalacia. A univariate comparison of median ADC values in all cerebral territories between fetuses with and those without adverse perinatal outcome was performed. The association between ADC values and adverse perinatal outcome was then analyzed using multilevel logistic regression models to adjust for other common prognostic factors for growth-restricted fetuses.

RESULTS

MRI was performed in 64 patients, of whom five were excluded owing to fetal movement artifacts on DWI and two were excluded for termination of pregnancy with no link to fetal growth restriction (FGR). One intrauterine death occurred secondary to severe FGR. Among the 56 liveborn neonates, delivered at a mean ± SD gestational age of 33.6 ± 3.0 weeks, with a mean birth weight of 1441 ± 566 g, four neonatal deaths occurred. In addition, two neonates required prolonged mechanical ventilation, one of whom also developed necrotizing enterocolitis. Overall, therefore, seven out of 57 (12.3%) cases had an adverse perinatal outcome (95% CI, 3.8-20.8%). The ADC values in the frontal region were significantly lower in the group with adverse perinatal outcome vs those in the group with favorable outcome (mean values of both hemispheres, 1.68 vs 1.78 × 10^-3  mm² /s; P = 0.04). No significant difference in ADC values was observed between the two groups in any other cerebral territory. A cut-off value of 1.70 × 10^-3  mm² /s was associated with a sensitivity of 57% (95% CI, 18-90%), a specificity of 78% (95% CI, 63-88%), a positive predictive value of 27% (95% CI, 8-55%) and a negative predictive value of 93% (95% CI, 80-98%) for the prediction of adverse perinatal outcome. A mean frontal ADC value < 1.70 × 10^-3  mm² /s was not associated significantly with an increased risk of adverse perinatal outcome, either in the univariate analysis (P = 0.07), or when adjusting for gestational age at MRI and fetal sex (odds ratio (OR), 6.06 (95% CI, 0.9-37.1), P = 0.051) or for umbilical artery Doppler (OR, 6.08 (95% CI, 0.89-41.44)).

CONCLUSION

This first prospective, multicenter, cohort study using DWI in the setting of SGA found lower ADC values in the frontal white-matter territory in fetuses with, compared with those without, adverse perinatal outcome. To determine the prognostic value of these changes, further standardized evaluation of the neurodevelopment of children born with growth restriction is required. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Antenatal cardiotocography with and without computer analysis in high-risk pregnancy: a randomized clinical trial

BACKGROUND

Cardiotocography or nonstress test is a technical means of recording the fetal heartbeat and uterine contractions for antenatal monitoring.

OBJECTIVE

This study aimed to evaluate whether antepartum cardiotocography with computer analysis (computerized cardiotocography) increases the incidence of cesarean delivery in women with high-risk pregnancies but without intrauterine growth restriction.

STUDY DESIGN

This was a parallel group nonblinded randomized clinical trial of singletons with high-risk pregnancies admitted for inpatient monitoring between 24 0/7 and 37 6/7 weeks' gestation. Eligible participants were randomly allocated in a 1:1 ratio to antenatal monitoring with either standard cardiotocography or computerized cardiotocography. Women randomized to the computerized cardiotocography arm received cardiotocographic monitoring with computerized analysis in a central monitoring station. The primary outcome was the incidence of cesarean delivery.

RESULTS

Overall, 28 women were enrolled in this trial. In addition, 14 women were randomized to the computerized cardiotocography group and 14 women to the control group. No woman was excluded after randomization or lost to follow-up. Cesarean delivery occurred in 9 women (64.3%) in the computerized cardiotocography group and 9 women (64.3%) in the control group (relative risk, 1.00; 95% confidence interval, 0.21-4.69).There was no significant between-group difference in preterm birth, gestational age at delivery, Apgar score, and birthweight.

CONCLUSION

Among women with high-risk pregnancies, use of computerized cardiotocography for antenatal monitoring did not result in a significant increase in cesarean delivery compared with standard cardiotocography. The results of this single-center randomized trial require confirmation in multicenter studies.

Society for Maternal-Fetal Medicine Consult Series #52: Diagnosis and management of fetal growth restriction: (Replaces Clinical Guideline Number 3, April 2012)

Fetal growth restriction can result from a variety of maternal, fetal, and placental conditions. It occurs in up to 10% of pregnancies and is a leading cause of infant morbidity and mortality. This complex obstetrical problem has disparate published diagnostic criteria, relatively low detection rates, and limited preventative and treatment options. The purpose of this Consult is to outline an evidence-based, standardized approach for the prenatal diagnosis and management of fetal growth restriction. The recommendations of the Society for Maternal-Fetal Medicine are as follows: (1) we recommend that fetal growth restriction be defined as an ultrasonographic estimated fetal weight or abdominal circumference below the 10th percentile for gestational age (GRADE 1B); (2) we recommend the use of population-based fetal growth references (such as Hadlock) in determining fetal weight percentiles (GRADE 1B); (3) we recommend against the use of low-molecular-weight heparin for the sole indication of prevention of recurrent fetal growth restriction (GRADE 1B); (4) we recommend against the use of sildenafil or activity restriction for in utero treatment of fetal growth restriction (GRADE 1B); (5) we recommend that a detailed obstetrical ultrasound examination (current procedural terminology code 76811) be performed with early-onset fetal growth restriction (<32 weeks of gestation) (GRADE 1B); (6) we recommend that women be offered fetal diagnostic testing, including chromosomal microarray analysis, when fetal growth restriction is detected and a fetal malformation, polyhydramnios, or both are also present regardless of gestational age (GRADE 1B); (7) we recommend that pregnant women be offered prenatal diagnostic testing with chromosomal microarray analysis when unexplained isolated fetal growth restriction is diagnosed at <32 weeks of gestation (GRADE 1C); (8) we recommend against screening for toxoplasmosis, rubella, or herpes in pregnancies with fetal growth restriction in the absence of other risk factors and recommend polymerase chain reaction for cytomegalovirus in women with unexplained fetal growth restriction who elect diagnostic testing with amniocentesis (GRADE 1C); (9) we recommend that once fetal growth restriction is diagnosed, serial umbilical artery Doppler assessment should be performed to assess for deterioration (GRADE 1C); (10) with decreased end-diastolic velocity (ie, flow ratios greater than the 95th percentile) or in pregnancies with severe fetal growth restriction (estimated fetal weight less than the third percentile), we suggest weekly umbilical artery Doppler evaluation (GRADE 2C); (11) we recommend Doppler assessment up to 2-3 times per week when umbilical artery absent end-diastolic velocity is detected (GRADE 1C); (12) in the setting of reversed end-diastolic velocity, we suggest hospitalization, administration of antenatal corticosteroids, heightened surveillance with cardiotocography at least 1-2 times per day, and consideration of delivery depending on the entire clinical picture and results of additional evaluation of fetal well-being (GRADE 2C); (13) we suggest that Doppler assessment of the ductus venosus, middle cerebral artery, or uterine artery not be used for routine clinical management of early- or late-onset fetal growth restriction (GRADE 2B); (14) we suggest weekly cardiotocography testing after viability for fetal growth restriction without absent/reversed end-diastolic velocity and that the frequency be increased when fetal growth restriction is complicated by absent/reversed end-diastolic velocity or other comorbidities or risk factors (GRADE 2C); (15) we recommend delivery at 37 weeks of gestation in pregnancies with fetal growth restriction and an umbilical artery Doppler waveform with decreased diastolic flow but without absent/reversed end-diastolic velocity or with severe fetal growth restriction with estimated fetal weight less than the third percentile (GRADE 1B); (16) we recommend delivery at 33-34 weeks of gestation for pregnancies with fetal growth restriction and absent end-diastolic velocity (GRADE 1B); (17) we recommend delivery at 30-32 weeks of gestation for pregnancies with fetal growth restriction and reversed end-diastolic velocity (GRADE 1B); (18) we suggest delivery at 38-39 weeks of gestation with fetal growth restriction when the estimated fetal weight is between the 3rd and 10th percentile and the umbilical artery Doppler is normal (GRADE 2C); (19) we suggest that for pregnancies with fetal growth restriction complicated by absent/reversed end-diastolic velocity, cesarean delivery should be considered based on the entire clinical scenario (GRADE 2C); (20) we recommend the use of antenatal corticosteroids if delivery is anticipated before 33 6/7 weeks of gestation or for pregnancies between 34 0/7 and 36 6/7 weeks of gestation in women without contraindications who are at risk of preterm delivery within 7 days and who have not received a prior course of antenatal corticosteroids (GRADE 1A); and (21) we recommend intrapartum magnesium sulfate for fetal and neonatal neuroprotection for women with pregnancies that are <32 weeks of gestation (GRADE 1A).

sFlt-1/PlGF ratio and timing of delivery in early-onset fetal growth restriction with antegrade umbilical artery flow

OBJECTIVE

To analyze the value of the soluble fms-like tyrosine kinase-1/placental growth factor (sFlt-1/PlGF) ratio in predicting the time to delivery in early-onset fetal growth restriction (FGR) with preserved antegrade umbilical artery (UA) flow at diagnosis.

METHODS

This was a prospective observational single-center cohort study of pregnancies with early-onset (< 32 + 0 weeks) FGR and antegrade UA flow, in which maternal serum sFlt-1/PlGF ratio was determined at diagnosis. FGR was defined as estimated fetal weight < 3^rd centile or < 10^th centile with UA pulsatility index > 95^th centile, fetal middle cerebral artery pulsatility index < 5^th centile or cerebroplacental ratio < 5^th centile. The previously described sFlt-1/PlGF ratio cut-off value of 85 for facilitating the diagnosis of pre-eclampsia was assessed in the prediction of the need to deliver in < 1 week and ≥ 4 weeks.

RESULTS

In total, 120 cases were included. There were 116 (96.7%) liveborn neonates and 108 (90.0%) perinatal survivors. Median (interquartile range (IQR)) gestational age at diagnosis of early-onset FGR was 27.1 (25.7-29.4) weeks. Median (IQR) sFlt-1/PlGF ratio at diagnosis was 196 (84-474). Ninety (75.0%) cases had a sFlt-1/PlGF ratio ≥ 85. Among pregnancies with a liveborn neonate, median (IQR) interval to delivery in the groups with sFlt-1/PlGF ratio < 85 and ≥ 85 was 41 (22-54) days and 11 (4-20) days, respectively (P < 0.01). The probability of having to deliver within 1 week after diagnosis was 0% and 35.6% in those with sFlt-1/PlGF ratio < 85 and ≥ 85, respectively (P = 0.03), and the probability of delaying delivery for ≥ 4 weeks was 72.4% and 19.5%, respectively (P < 0.01).

CONCLUSION

sFlt-1/PlGF ratio < 85 at diagnosis of early-onset FGR with antegrade UA flow identifies a group of pregnancies in which the need to deliver within 1 week is very low and the interval to delivery is expected to be prolonged for ≥ 4 weeks in > 70% of cases. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Computerized fetal heart rate analysis in early preterm fetal growth restriction

OBJECTIVE

To assess the value of computerized cardiotocography (cCTG) with calculation of fetal heart rate (FHR) short-term variability (STV) in early preterm fetal growth restriction (FGR) for prevention of fetal death and neonatal asphyxia, neonatal morbidity, and 2-year neurodevelopmental impairment.

METHODS

This was a retrospective cohort study of all women who were admitted to the Amsterdam University Medical Center-AMC between 2003 and 2015 due to FGR and/or pre-eclampsia, and who were delivered by prelabor Cesarean section, or had a fetal death, before 32 weeks' gestation. STV of all available cCTG registrations during the 5 days preceding fetal death or delivery was calculated retrospectively, and FHR decelerations were classified visually as absent, 1-2/h or recurrent (> 2/h). Adverse outcome endpoints were defined as fetal death, neonatal asphyxia at birth (including fetal death), neonatal death, major neonatal morbidity and 2-year neurodevelopmental outcome. A simulation analysis was performed to assess the incidence of adverse outcome using two thresholds for cCTG: (1) highly abnormal (STV < 2.6 ms before 29 weeks and < 3.0 ms thereafter, and/or recurrent FHR decelerations); and (2) moderately abnormal (STV < 3.5 ms before 29 weeks and < 4.0 ms thereafter, and/or recurrent FHR decelerations). Three management strategies were assessed using a strict schedule for the frequency of cCTG recordings: (1) cCTG without use of fetal arterial Doppler; (2) cCTG with additional fetal arterial Doppler after 29 weeks; and (3) cCTG with additional fetal arterial Doppler after 27 weeks.

RESULTS

Included were 367 pregnancies (3295 cCTG recordings), of which 20 resulted in fetal death and 347 were delivered by Cesarean section before the onset of labor. Cesarean delivery was indicated by fetal condition in 94% of cases and by maternal condition in 6%. Median gestational age at delivery was 30 (interquartile range (IQR), 28-31) weeks and median birth weight was 900 (IQR, 740-1090) g. Six cases of fetal death were not anticipated by standard practice using visual assessment of CTG. A last highly abnormal cCTG was associated with fetal death and with neonatal asphyxia (including fetal death; n = 99), but not with major neonatal morbidity and 2-year neurodevelopmental outcome. Moderately abnormal cCTG had no significant association with any endpoint. Simulation analysis showed that a strategy that combined cCTG results with umbilicocerebral ratio or umbilical absent or reversed end-diastolic flow could detect all fetal deaths.

CONCLUSIONS

Computerized CTG in combination with fetal arterial Doppler, with a strict protocol for the frequency of recordings, is likely to be more effective than visual CTG assessment for preventing fetal death in early preterm FGR. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Ductus venosus Doppler waveform pattern in fetuses with early growth restriction

INTRODUCTION

We aimed to assess if maximum velocities of the ductus venosus flow velocity waveform are associated with adverse outcomes in early-onset fetal growth restriction.

MATERIAL AND METHODS

Retrospective cohort study from two tertiary referral units, including singleton fetuses with estimated birthweight or fetal abdominal circumference ≤10th centile and absent or reversed end-diastolic velocity in the umbilical artery delivered between 26⁺⁰ and 34⁺⁰  weeks of gestation. Pulsatility index for veins, and maximum velocities of S-, D-, v- and a-waves, were measured in the ductus venosus within 24 hours of birth. Logistic regression was used to describe the relation between severe neonatal morbidity or neonatal death and clinical independent predictors.

RESULTS

The study population included 132 early-onset fetal growth restriction fetuses. Newborns with neonatal morbidity or neonatal death had significantly lower values of v/D maximum velocity ratio multiples of the median (0.86 vs 095; P = 0.006) within 24 hours of birth. The v/D ratio remained a significant predictor of neonatal death or severe neonatal morbidity after adjusting for gestational age and birthweight (adjusted odds ratio 0.065, 95% confidence interval 0.004-0.957).

CONCLUSIONS

Assessment of ductus venosus v/D maximum velocity ratio might help to identify fetal growth restriction fetuses at increased risk for neonatal death or severe neonatal morbidity. Confirmation in prospective studies is necessary.

Heparin therapy in placental insufficiency: Systematic review and meta-analysis

INTRODUCTION

The objective of this study was to establish whether heparin improves the neonatal outcome of fetuses with suspected placental insufficiency.

MATERIAL AND METHODS

Before data extraction, the project was registered in the PROSPERO International Prospective Register of Systematic Reviews (registration number: CRD42019117627). A systematic search was performed to identify relevant studies, using PubMed, SCOPUS, ISI Web of Knowledge, and PROSPERO database for meta-analysis. Suspected placental insufficiency was defined as either an estimated fetal weight or abdominal circumference below the 10th centile or when at least 2 of the following criteria were met: (1) abnormal biochemical markers, (2) sonographic evidence of abnormal placental morphology, or (3) abnormal uterine artery Doppler. Heparin in any commercial presentation was defined as the intervention. Mean difference (MD) by random effects model was used. Heterogeneity between studies was assessed using Cochran's Q, H, and I² statistics.

RESULTS

From 1159 assessed studies, two were retained for analysis. The results showed a significantly higher birthweight (MD 365; 95% CI 236 to 494; P < 0.001) and a significant increase of gestational age at birth by 1 week in those women treated with heparin (MD 0.806; 95% CI 0.354 to 1.258; P < 0.001). However, there were no significant differences in Apgar scores, neonatal admission, neonatal mortality, or composite neonatal morbidity.

CONCLUSIONS

In women with very high suspicion of placental insufficiency, heparin may increase fetal growth and prolong pregnancy. There is no evidence for a beneficial effect of heparin in reducing neonatal adverse outcomes.

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.

Chronic gestational hypoxia accelerates ovarian aging and lowers ovarian reserve in next-generation adult rats

Chronic fetal hypoxia is a common complication observed in human pregnancy, impacting pregnancies across global contexts. Exposure to chronic intrauterine hypoxia has major short- and long-term consequences for offspring health. However, the impact of chronic gestational hypoxia on female reproductive system development is unknown. We aimed to understand the impact of exposure to chronic fetal hypoxia on the developing female reproductive system. Wistar rat dams underwent normoxia (21%) or hypoxia (13%) during pregnancy. Postnatally, all female offspring were maintained in normoxic conditions into early adulthood. Female rats exposed to chronic gestational hypoxia (13%) during their intrauterine development had decreased ovarian primordial follicular reserve compared to controls (P < 0.05). Adult females who had been exposed to chronic fetal hypoxia had significantly reduced somatic ovarian telomere length (P < 0.05) and reduced ovarian protein expression of KU70, a critical component of the DNA-activated protein kinase repair complex (P < 0.01). Gene expression of NADPH oxidase 2-mediated oxidative stress markers was increased (P < 0.05). Exposure to chronic hypoxia during fetal development leads to accelerated aging of the somatic ovary and decreased ovarian reserve in adulthood. Ovarian aging is highly sensitive to gestational hypoxia, with implications for future fertility in next-generation offspring of high-risk pregnancies.-Aiken, C. E., Tarry-Adkins, J. L., Spiroski, A.-M., Nuzzo, A. M., Ashmore, T. J., Rolfo, A., Sutherland, M. J., Camm, E. J., Giussani, D. A., Ozanne, S. E. Chronic gestational hypoxia accelerates ovarian aging and lowers ovarian reserve in next-generation adult rats.

Iatrogenic late preterm birth: when is it recommended? A Delphi survey promoted by the Italian Society of Perinatal Medicine

BACKGROUND

The rate of iatrogenic Late Preterm (LP) Birth varies in different settings. This is due to the lack of strong evidence/guidelines on the management of the different maternal, fetal and placental complications affecting pregnancy in the LP window. Steroid prophylaxis is also under discussion.

AIM

To build recommendations about the management of main medical complications (pregestational diabetes, placenta previa, preeclampsia, cholestasis, p-PROM, intrauterine growth restriction -IUGR-) occurring in the LP period to reduce clinical heterogeneity.

METHODS

A group of Italian Perinatal experts were identified by Scientific Societies. A Delphi consensus methodology was used to reach agreement on different clinical sceneries. Two rounds of consultation by using a purpose built on-line survey and a third open panel discussion were performed.

RESULTS

The panel of 50 experts reached agreement for the vast majority of clinical sceneries (Placenta Previa, Preeclampsia, Diabetes, Cholestasis). Overall, there was agreement to be conservative at 34 weeks and in favor of delivery at 36 weeks. The management of p-PROM and mostly of IUGR were characterized by a minor degree of consensus. Corticosteroids were found necessary at the 34th week and unnecessary at the 36th week.

CONCLUSIONS

Besides providing some guidance on clinical indications for LP iatrogenic delivery, these results represent a stimulus for designing future trials investigating the grey areas in this field.

Renal artery Doppler compared with the cerebral placental ratio to identify fetuses at risk for adverse neonatal outcome

Background: Current clinical practice incorporates an umbilical artery resistance index or a ratio of the middle cerebral artery (MCA PI) to the umbilical artery pulsatility index (UA PI) known as the cerebral placental ratio (CPR) to assess wellbeing in the small for gestational age fetus. Previous reports using the renal artery Doppler indices have not been consistent in regards to their design and clinical use. Our objective is to develop reference values for renal artery Doppler indices and validate their use compared with the UA PI or CPR to identify fetuses that will develop a composite neonatal outcome.Methods: We performed 9700 ultrasounds among 2852 women at 20-40 weeks of gestation at the University of Maryland between 1 June 2016 and 1 December 2016. Nomograms were first developed using one randomly selected scan from each of a subgroup of 860 women without any comorbidities. The nomograms were validated among a cohort of 550 women who subsequently delivered at the University of Maryland Medical Center. We compared the area under the receiver operating characteristic curve (AUROC) between the CPR and UA PI, and the renal artery Doppler parameters (renal artery pulsatility index (RA PI), systolic diastolic ratio (RA SDR), and peak systolic velocity (RA PSV)). The primary outcome was the development any one of the composite neonatal outcome components (death, intensive care unit admission, ventilator for more than 6 h, hypoxic ischemic encephalopathy or necrotizing enterocolitis) or admission to the neonatal intensive care unit (NICU) for any indication.Results: The renal artery Doppler indices did not improve identification of fetuses that would subsequently develop one of the components of the composite neonatal outcome (AUROC for CPR 0.54, 95% CI (0.49-0.59), versus the UA PI: 0.59 (0.54-0.64) p = .07, the RA PI: 0.51 (0.48-0.55) p = .41, RA SDR 0.54 (0.49-0.58) p = .99, or RA PSV 0.51 (0.47-0.55) p = .37). There was no difference when comparing AUROC to detect NICU admission (AUROC for CPR 0.53, 95% CI (0.49-0.58), versus the UA PI: 0.57 (0.52-0.62) p = .14, the RA PI: 0.50 (0.47-0.54) p = .44, RA SDR: 0.54 (0.50-0.59) p = .62 or RAPSV: 0.51 (0.47-0.55) p = .54).Conclusion: The renal artery indices do not improve detection of fetuses at risk for adverse neonatal outcomes compared with the CPR or the UA PI.

Threshold of metabolic acidosis associated with newborn cerebral palsy: medical legal implications

Obstetricians and gynecologists belong to 1 of the medical specialties with the highest rate of litigation claims. Among birth injury cases, those cases with cerebral palsy outcomes account for litigation settlements or judgments often in the millions of dollars. In cases of potential perinatal asphyxia, a threshold level of metabolic acidosis (base deficit ≥12 mmol/L) is necessary to attribute neonatal encephalopathy to an intrapartum hypoxic event. With increasing duration or severity of a hypoxic stress resulting in metabolic acidosis, newborn infant umbilical artery base deficit increases. It may be alleged that, as base deficit levels increase beyond 12 mmol/L, there is an increased likelihood and severity of cerebral palsy. As a corollary, it may be claimed that an earlier delivery (by minutes) would reduce the base deficit and prevent or reduce the severity of cerebral palsy. This issue is of relevance to obstetricians as defendants, because retrospective "expert" analysis of cases may suggest that optimal management decisions would have resulted in an earlier delivery. In addressing the association of metabolic acidosis and cerebral palsy, base deficit should be measured as the extracellular component (base deficit_{extracellular fluid}) rather than the commonly used base deficit_blood. Studies suggest that, beyond the base deficit threshold of 12 mmol/L, the incidence and severity of cerebral palsy does not significantly increase (until ≥20 mmol/L), although the risk of neonatal death rises markedly. Thus, among most infants with hypoxia-associated neonatal encephalopathy, the occurrence of cerebral palsy is unlikely to be impacted by delivery time variation of few minutes, and this argument should not serve as the basis for medical legal claims.

Longitudinal change of sFlt-1/PlGF ratio in singleton pregnancy with early-onset fetal growth restriction

OBJECTIVE

To describe the evolution of soluble fms-like tyrosine kinase-1 to placental growth factor (sFlt-1/PlGF) ratio in the last 5 weeks prior to delivery in singleton pregnancy complicated by early-onset fetal growth restriction (FGR), with or without pre-eclampsia (PE).

METHODS

This was a prospective observational cohort study of early-onset FGR cases that underwent serial assessment of maternal serum sFlt-1/PlGF ratio from diagnosis to delivery. Measurements were made at weekly intervals and within the last 48 h before birth. Absolute values and percentage increase between time intervals were computed, and previously described cut-off values of 38 (suspicion of PE), 85 (aids diagnosis of PE) and 655 (high risk for imminent delivery) were used for analysis of the sFlt-1/PlGF ratio. We compared findings between cases with early-onset FGR only (n = 37) and those that additionally developed PE (n = 36).

RESULTS

Overall perinatal survival was 63/73 (86.3%). A sFlt-1/PlGF ratio above 38 was observed 4 weeks before delivery in most FGR-only and FGR with PE cases (73% and 100%, respectively), but absolute values of sFlt-1/PlGF were significantly higher in FGR cases with PE. Extremely elevated values of the ratio (≥ 655) within the last 48 h before delivery were found in 65% of cases of FGR with PE, but in only 8% of isolated FGR cases (P < 0.001).

CONCLUSION

Elevated sFlt-1/PlGF was observed in most early-onset FGR pregnancies from 4 weeks before delivery, and values were even higher if there was concurrent PE. However, serial measurements of the ratio were of limited value, being useful only to anticipate the need for imminent delivery in cases of FGR with PE when sFlt-1/PlGF values ≥ 655 were reached. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Screening for fetal growth restriction and placental insufficiency

Fetal growth restriction (FGR) continues to be a leading cause of preventable stillbirth and poor neurodevelopmental outcomes in offspring, and furthermore is strongly associated with the obstetrical complications of iatrogenic preterm birth and pre-eclampsia. The terms small for gestational age (SGA) and FGR have, for too long, been considered equivalent and therefore used interchangeably. However, the delivery of improved clinical outcomes requires that clinicians effectively distinguish fetuses that are pathologically growth-restricted from those that are constitutively small. A greater understanding of the multifactorial pathogenesis of both early- and late-onset FGR, especially the role of underlying placental pathologies, may offer insight into targeted treatment strategies that preserve placental function. The new maternal blood biomarker placenta growth factor offers much potential in this context. This review highlights new approaches to effective screening for FGR based on a comprehensive review of: etiology, diagnosis, antenatal surveillance and management. Recent advances in novel imaging methods provide the basis for stepwise multi-parametric testing that may deliver cost-effective screening within existing antenatal care systems.

Planning management and delivery of the growth-restricted fetus

A uniform approach to management of fetal growth restriction (FGR) improves outcome, prevents stillbirth, and allows appropriately timed delivery. An estimated fetal weight below the tenth percentile with coexisting abnormal umbilical artery (UA), middle cerebral artery (MCA), or cerebroplacental ratio Doppler index best identifies the small fetus requiring surveillance. Placental perfusion defects are more common earlier in gestation; accordingly, early-onset (≤32 weeks of gestation) and late-onset (>32 weeks) FGR differ in clinical phenotype. In early-onset FGR, progression of UA Doppler abnormality determines clinical acceleration, while abnormal ductus venosus (DV) Doppler precedes deterioration of biophysical variables and stillbirth. Accordingly, late DV Doppler changes, abnormal biophysical variables, or an abnormal cCTG require delivery. In late-onset FGR, MCA Doppler abnormalities precede deterioration and stillbirth. However, from 34 to 38 weeks, randomized evidence on optimal delivery timing is lacking. From 38 weeks onward, the balance of neonatal versus fetal risks favors delivery.

Risk of fetal death in growth-restricted fetuses with umbilical and/or ductus venosus absent or reversed end-diastolic velocities before 34 weeks of gestation: a systematic review and meta-analysis

OBJECTIVE

The objective of the study was to establish the risk of fetal death in early-onset growth-restricted fetuses with absent or reversed end-diastolic velocities in the umbilical artery or ductus venosus.

DATA SOURCES

A systematic search was performed to identify relevant studies published in English, Spanish, French, Italian, or German using the databases PubMed, ISI Web of Science, and SCOPUS, without publication time restrictions.

STUDY ELIGIBILITY CRITERIA

The study criteria included observational cohort studies and randomized controlled trials of early-onset growth-restricted fetuses (diagnosed before 34 weeks of gestation), with information on the rate of fetal death occurring before 34 weeks of gestation and absent or reversed end-diastolic velocities in the umbilical artery and/or ductus venosus.

STUDY APPRAISAL AND SYNTHESIS METHODS

For quality assessment, 2 reviewers independently assessed the risk of bias using the Newcastle-Ottawa Scale for observational studies and the Cochrane Collaboration's tool for randomized trials. For the meta-analysis, odds ratio for both fixed and random-effects models (weighting by inverse of variance) were used. Heterogeneity between studies was assessed using tau², χ2 (Cochrane Q), and I² statistics. Publication bias was assessed by a funnel plot for meta-analyses and quantified by the Egger method.

RESULTS

A total of 31 studies were included in this meta-analysis. The odds ratios for fetal death (random-effects models) were 3.59 (95% confidence interval, 2.3-5.6), 7.27 (95% confidence interval, 4.6-11.4), and 11.6 (95% confidence interval, 6.3-19.7) for growth-restricted fetuses with umbilical artery absent end-diastolic velocities, umbilical artery reversed end-diastolic velocities, and ductus venosus absent or reversed end-diastolic velocities, respectively. There was no substantial heterogeneity among studies for any of the analyses.

CONCLUSION

Early-onset growth-restricted fetuses with either umbilical artery or ductus venosus absent or reserved end-diastolic velocities are at a substantially increased risk for fetal death.