Comparative analysis of 2-year outcomes in GRIT and TRUFFLE trials

Fetal growth restriction adversely impacts trajectory of hippocampal neurodevelopment and function

The last pregnancy trimester is critical for fetal brain development but is a vulnerable period if the pregnancy is compromised by fetal growth restriction (FGR). The impact of FGR on the maturational development of neuronal morphology is not known, however, studies in fetal sheep allow longitudinal analysis in a long gestation species. Here we compared hippocampal neuron dendritogenesis in FGR and control fetal sheep at three timepoints equivalent to the third trimester of pregnancy, complemented by magnetic resonance image for brain volume, and electrophysiology for synaptic function. We hypothesized that the trajectory of hippocampal neuronal dendrite outgrowth would be decreased in the growth-restricted fetus, with implications for hippocampal volume, connectivity, and function. In control animals, total dendrite length increased with advancing gestation, but not in FGR, resulting in a significantly reduced trajectory of dendrite outgrowth in FGR fetuses for total length, branching, and complexity. Ex vivo electrophysiology analysis shows that paired-pulse facilitation was reduced in FGR compared to controls for cornu ammonis 1 hippocampal outputs, reflecting synaptic dysfunction. Hippocampal brain-derived neurotrophic factor density decreased over late gestation in FGR fetuses but not in controls. This study reveals that FGR is associated with a significant deviation in the trajectory of dendrite outgrowth of hippocampal neurons. Where dendrite length significantly increased over the third trimester of pregnancy in control brains, there was no corresponding increase over time in FGR brains, and the trajectory of dendrite outgrowth in FGR offspring was significantly reduced compared to controls. Reduced hippocampal dendritogenesis in FGR offspring has severe implications for the development of hippocampal connectivity and long-term function.

Late-onset fetal growth restriction management: a national survey

BACKGROUND

Fetal growth restriction (FGR) is an obstetric condition that increases the risk of adverse neonatal outcomes. FGR antenatal care aims to decrease fetal morbidity and mortality through optimal fetal monitoring. However, no univocal strategies for late-onset FGR outpatient management are available, and this survey investigated gynaecologists' attitudes concerning outpatient frequency tests.

METHODS

We mailed a survey to 429 Italian gynaecologists. The primary purpose was the ambulatory care of late-onset FGR without doppler alterations evaluation. The queries estimated the self-reported medical practice regarding cardiotocography (CTG) and obstetric ultrasound exams before hospitalization. Statistical analysis was performed with Stata 14.1 (Stata corp., College Station, TX, USA) for symmetrically distributed continuous variables, and the mean differences were analyzed using the t-test. Where appropriate, the proportions between the groups were evaluated using Fisher's exact or χ2 test. All P value <0.05 were considered statistically significant.

RESULTS

128 responses (29.8%) from the 429 SCCAL members were available for the survey. 39.9% of respondents had a late FGR standardized protocol. Regarding non-severe FGR with normal fetal doppler, 70.8% suggested a fetal doppler study after one week (92/128), 13.8% (18/128) and 6.9% (9/128) proposed the exam, respectively, two and three times for a week. 0.8% (1/128) of respondents had a daily doppler exam, 7.7% (10/128) did not answer, and 3.1% (4/128) repeated the ultrasound exam to time for a week. The antenatal CTG was offered: 70.8% (92/128) of gynaecologists recommended one weekly CTG, whereas 13.8% (18/128) suggested two. 6.9% (9/128) recommended three weekly tests and 0.8% a daily test. 7.7% (10/128) of gynaecologists did not respond. At least, we investigated the gynaecologist's recommendations for outpatient EFW evaluation: 59.4% (76/128) repeated EFW after two weeks, 31.3% (40/128) after one week. 3.9% (4/128) and 3.1 (4/128) recommended EFW after three weeks and twice a week.

CONCLUSIONS

Gynaecologists recommend unnecessary cardiotocography and ultrasound Doppler exams for non-severe late-onset FGR with normal doppler. However, additional studies and comprehensive surveys are needed to support a standardized protocol and assess the feto-maternal outcomes impact.

Prediction of adverse neonatal adaptation in fetuses with severe fetal growth restriction after 34 weeks of gestation

OBJECTIVE

To establish a predictive model for adverse immediate neonatal adaptation (INA) in fetuses with suspected severe fetal growth restriction (FGR) after 34 gestational weeks (GW).

METHODS

We conducted a retrospective observational study at the University Hospitals of Strasbourg between 2000 and 2020, including 1,220 women with a singleton pregnancy and suspicion of severe FGR who delivered from 34 GW. The primary outcome (composite) was INA defined as Apgar 5-minute score <7, arterial pH <7.10, immediate transfer to pediatrics, or the need for resuscitation at birth. We developed and tested a logistic regression predictive model.

RESULTS

Adverse INA occurred in 316 deliveries. The model included six features available before labor: parity, gestational age, diabetes, middle cerebral artery Doppler, cerebral-placental inversion, onset of labor. The model could predict individual risk of adverse INA with confidence interval at 95 %. Taking an optimal cutoff threshold of 32 %, performances were: sensitivity 66 %; specificity 83 %; positive and negative predictive values 60 % and 87 % respectively, and area under the curve 78 %.

DISCUSSION

The predictive model showed good performances and a proof of concept that INA could be predicted with pre-labor characteristics, and needs to be investigated further.

Maternal PlGF and umbilical Dopplers predict pregnancy outcomes at diagnosis of early-onset fetal growth restriction

BACKGROUNDSevere, early-onset fetal growth restriction (FGR) causes significant fetal and neonatal mortality and morbidity. Predicting the outcome of affected pregnancies at the time of diagnosis is difficult, thus preventing accurate patient counseling. We investigated the use of maternal serum protein and ultrasound measurements at diagnosis to predict fetal or neonatal death and 3 secondary outcomes: fetal death or delivery at or before 28+0 weeks, development of abnormal umbilical artery (UmA) Doppler velocimetry, and slow fetal growth.METHODSWomen with singleton pregnancies (n = 142, estimated fetal weights [EFWs] below the third centile, less than 600 g, 20+0 to 26+6 weeks of gestation, no known chromosomal, genetic, or major structural abnormalities) were recruited from 4 European centers. Maternal serum from the discovery set (n = 63) was analyzed for 7 proteins linked to angiogenesis, 90 additional proteins associated with cardiovascular disease, and 5 proteins identified through pooled liquid chromatography and tandem mass spectrometry. Patient and clinician stakeholder priorities were used to select models tested in the validation set (n = 60), with final models calculated from combined data.RESULTSThe most discriminative model for fetal or neonatal death included the EFW z score (Hadlock 3 formula/Marsal chart), gestational age, and UmA Doppler category (AUC, 0.91; 95% CI, 0.86-0.97) but was less well calibrated than the model containing only the EFW z score (Hadlock 3/Marsal). The most discriminative model for fetal death or delivery at or before 28+0 weeks included maternal serum placental growth factor (PlGF) concentration and UmA Doppler category (AUC, 0.89; 95% CI, 0.83-0.94).CONCLUSIONUltrasound measurements and maternal serum PlGF concentration at diagnosis of severe, early-onset FGR predicted pregnancy outcomes of importance to patients and clinicians.TRIAL REGISTRATIONClinicalTrials.gov NCT02097667.FUNDINGThe European Union, Rosetrees Trust, Mitchell Charitable Trust.

Diagnostic Tests in the Prediction of Neonatal Outcome in Early Placental Fetal Growth Restriction

Background and Objectives: Monitoring pregnancies with fetal growth restriction (FGR) presents a challenge, especially concerning the time of delivery in cases of early preterm pregnancies below 32 weeks. The aim of our study was to compare different diagnostic parameters in growth-restricted preterm neonates with and without morbidity/mortality and to determine sensitivity and specificity of diagnostic parameters for monitoring preterm pregnancies with early preterm fetal growth restriction below 32 weeks. Materials and Methods: Our clinical study evaluated 120 cases of early preterm deliveries, with gestational age ≤ 32 + 0 weeks, with prenatally diagnosed placental FGR. All the patients were divided into three groups of 40 cases each based on neonatal condition,: I-Neonates with morbidity/mortality (NMM); II-Neonates without morbidity with acidosis/asphyxia (NAA); III-Neonates without neonatal morbidity/acidosis/asphyxia (NWMAA). Results: Amniotic fluid index (AFI) was lower in NMM, while NWMAA had higher biophysical profile scores (BPS). UA PI was lower in NWMAA. NWMAA had higher MCA PI and CPR and fewer cases with CPR <5th percentile. NMM had higher DV PI, and more often had ductus venosus (DV) PI > 95th‱ or absent/reversed A wave, and pulsatile blood flow in umbilical vein (UV). The incidence of pathological fetal heart rate monitoring (FHRM) was higher in NMM and NAA, although the difference was not statistically significant. ROC calculated by defining a bad outcome as NMM and a good outcome as NAA and NWMAA showed the best sensitivity in DV PIi. ROC calculated by defined bad outcome in NMM and NAA and good outcome in NWMAA showed the best sensitivity in MCA PI. Conclusions: In early fetal growth restriction normal cerebral blood flow strongly predicts good outcomes, while pathological venous blood flow is associated with bad outcomes. In fetal growth restriction before 32 weeks, individualized expectant management remains the best option for the optimal timing of delivery.

Fetal growth restriction and stillbirth: Biomarkers for identifying at risk fetuses

Fetal growth restriction (FGR) is a major cause of stillbirth, prematurity and impaired neurodevelopment. Its etiology is multifactorial, but many cases are related to impaired placental development and dysfunction, with reduced nutrient and oxygen supply. The fetus has a remarkable ability to respond to hypoxic challenges and mounts protective adaptations to match growth to reduced nutrient availability. However, with progressive placental dysfunction, chronic hypoxia may progress to a level where fetus can no longer adapt, or there may be superimposed acute hypoxic events. Improving detection and effective monitoring of progression is critical for the management of complicated pregnancies to balance the risk of worsening fetal oxygen deprivation in utero, against the consequences of iatrogenic preterm birth. Current surveillance modalities include frequent fetal Doppler ultrasound, and fetal heart rate monitoring. However, nearly half of FGR cases are not detected in utero, and conventional surveillance does not prevent a high proportion of stillbirths. We review diagnostic challenges and limitations in current screening and monitoring practices and discuss potential ways to better identify FGR, and, critically, to identify the “tipping point” when a chronically hypoxic fetus is at risk of progressive acidosis and stillbirth.

Associations of severe adverse perinatal outcomes among continuous birth weight percentiles on different birth weight charts: a secondary analysis of a cluster randomized trial

Objective

To identify neonatal risk for severe adverse perinatal outcomes across birth weight centiles in two Dutch and one international birth weight chart.

Background

Growth restricted newborns have not reached their intrinsic growth potential in utero and are at risk of perinatal morbidity and mortality. There is no golden standard for the confirmation of the diagnosis of fetal growth restriction after birth. Estimated fetal weight and birth weight below the 10^th percentile are generally used as proxy for growth restriction. The choice of birth weight chart influences the specific cut-off by which birth weight is defined as abnormal, thereby triggering clinical management. Ideally, this cut-off should discriminate appropriately between newborns at low and at high risk of severe adverse perinatal outcomes and consequently correctly inform clinical management.

Methods

This is a secondary analysis of the IUGR Risk Selection (IRIS) study. Newborns (n = 12 953) of women with a low-risk status at the start of pregnancy and that received primary antenatal care in the Netherlands were included.

We examined the distribution of severe adverse perinatal outcomes across birth weight centiles for three birth weight charts (Visser, Hoftiezer and INTERGROWTH) by categorizing birth weight centile groups and comparing the prognostic performance for severe adverse perinatal outcomes.

Severe adverse perinatal outcomes were defined as a composite of one or more of the following: perinatal death, Apgar score < 4 at 5 min, impaired consciousness, asphyxia, seizures, assisted ventilation, septicemia, meningitis, bronchopulmonary dysplasia, intraventricular hemorrhage, periventricular leukomalacia, or necrotizing enterocolitis.

Results

We found the highest rates of severe adverse perinatal outcomes among the smallest newborns (< 3^rd percentile) (6.2% for the Visser reference curve, 8.6% for the Hoftiezer chart and 12.0% for the INTERGROWTH chart). Discriminative abilities of the three birth weight charts across the entire range of birth weight centiles were poor with areas under the curve ranging from 0.57 to 0.61. Sensitivity rates of the various cut-offs were also low.

Conclusions

The clinical utility of all three charts in identifying high risk of severe adverse perinatal outcomes is poor. There is no single cut-off that discriminates clearly between newborns at low or high risk.

Trial Registration

Netherlands Trial Register NTR4367.

Registration date March 20^th, 2014.

Short-term outcomes of phosphodiesterase type 5 inhibitors for fetal growth restriction: a study protocol for a systematic review with individual participant data meta-analysis, aggregate meta-analysis, and trial sequential analysis

BACKGROUND

Early onset fetal growth restriction secondary to placental insufficiency can lead to severe maternal and neonatal morbidity and mortality. Pre-clinical studies and a few small randomised clinical trials have suggested that phosphodiesterase type 5 (PDE-5) inhibitors may have protective effects against placental insufficiency in this context; however, robust evidence is lacking. The STRIDER Consortium conducted four randomised trials to investigate the use of a PDE-5 inhibitor, sildenafil, for the treatment of early onset fetal growth restriction. We present a protocol for the pre-planned systematic review with individual participant data meta-analysis, aggregate meta-analysis, and trial sequential analysis of these and other eligible trials. The main objective of this study will be to evaluate the effects of PDE-5 inhibitors on neonatal morbidity compared with placebo or no intervention among pregnancies with fetal growth restriction.

METHODS

We will search the following electronic databases with no language or date restrictions: OVID MEDLINE, OVID EMBASE, the Cochrane Controlled Register of Trials (CENTRAL), and the clinical trial registers Clinicaltrials.gov and World Health Organisation International Clinical Trials Registry Platform (ICTRP). We will identify randomised trials of PDE-5 inhibitors in singleton pregnancies with growth restriction. Two reviewers will independently screen all citations, full-text articles, and abstract data. Our primary outcome will be infant survival without evidence of serious adverse neonatal outcome. Secondary outcomes will include gestational age at birth and birth weight z-scores. We will assess bias using the Cochrane Risk of Bias 2 tool. We will conduct aggregate meta-analysis using fixed and random effects models, Trial Sequential Analysis, and individual participant data meta-analysis using one- and two-stage approaches. The certainty of evidence will be assessed with GRADE.

DISCUSSION

This pre-defined protocol will minimise bias during analysis and interpretation of results, toward the goal of providing robust evidence regarding the use of PDE-5 inhibitors for the treatment of early onset fetal growth restriction.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO (CRD42017069688).

Neuroimaging and neurodevelopmental outcome after early fetal growth restriction: NEUROPROJECT-FGR

BACKGROUND

Adverse neurodevelopmental outcomes and MRI alterations are reported in infants born after fetal growth restriction (FGR). This study evaluates the additional role of FGR over prematurity in determining brain impairment.

METHODS

Retrospective observational study comparing 48 FGR and 36 appropriate for gestational age infants born between 26 and 32 weeks' gestation who underwent a cerebral MRI at term equivalent age. Exclusion criteria were twins, congenital anomalies, and findings of overt brain lesions. Main outcomes were total maturation score (TMS) and cerebral areas independently measured by two neuro-radiologists and Griffiths or Bayley scale III scores at median age of 2 years.

RESULTS

TMS was not significantly different between the groups. Inner calvarium and parenchyma's areas were significantly smaller in FGR cases. There were no significant differences in the average quotient scores. A positive correlation between parenchyma area and cognitive score was found (r = 0.372, p = 0.0078) and confirmed after adjusting for sex, gestational age, and birth weight (p = 0.0014). Among FGR, the subgroup with umbilical arterial Doppler velocimetry alterations had significantly worse gross motor scores (p = 0.005).

CONCLUSIONS

FGR plays additional role over prematurity in determining brain impairment. An early structural dimensional MRI evaluation may identify infants who are at higher risk.

IMPACT

Fetal growth-restricted infants showed smaller cerebral parenchymal areas than preterm controls. There is a positive correlation between the parenchyma area and the cognitive score. These results highlight the already known link between structure and function and add importance to the role of a structural dimensional MRI evaluation even in the absence of overt brain lesions.

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.

Prediction of Adverse Pregnancy Outcome Related to Placental Dysfunction Using the sFlt-1/PlGF Ratio: A Narrative Review

The sFlt-1 (soluble fms-like tyrosine kinase-1)/PlGF (placental growth factor) ratio is a helpful tool for the prediction and diagnosis of preeclampsia (PE). Current data even show that the ratio has the potential to predict adverse pregnancy outcomes (APO) caused by placental pathologies. The aim of this article is to give a brief overview of recent findings on APO predictions based on the sFlt-1/PlGF ratio. The focus is on obstetric pathologies related to placental dysfunction (PD) such as PE and/or fetal growth restriction (FGR). New uses of the sFlt-1/PlGF ratio as a predictor of APO demonstrate its potential with regard to planning hospitalization and corticosteroid administration and the optimal timing of delivery. However, prospective interventional studies are warranted to define the exact role of the sFlt-1/PlGF ratio as a predictor of adverse pregnancy outcomes caused by placental pathologies.

Molecular Pathways of Cellular Senescence and Placental Aging in Late Fetal Growth Restriction and Stillbirth

Abnormally accelerated, premature placental senescence plays a crucial role in the genesis of pregnancy pathologies. Abnormal growth in the third trimester can present as small for gestational age fetuses or fetal growth restriction. One differs from the other by the presence of signs of placental insufficiency and the risk of stillbirth. The majority of stillbirths occur in normally grown fetuses and are classified as "unexplained", which often leads to conclusions that they were unpreventable. The main characteristic of aging is a gradual decline in the function of cells, tissues, and organs. These changes result in the accumulation of senescent cells in mitotic tissues. These cells begin the aging process that disrupts tissues' normal functions by affecting neighboring cells, degrading the extracellular matrix, and reducing tissues' regeneration capacity. Different degrees of abnormal placentation result in the severity of fetal growth restriction and its sequelae, including fetal death. This review aims to present the current knowledge and identify future research directions to understand better placental aging in late fetal growth restriction and unexplained stillbirth. We hypothesized that the final diagnosis of placental insufficiency can be made only using markers of placental senescence.

A hierarchical procedure to select intrauterine and extrauterine factors for methodological validation of preterm birth risk estimation

Background

Etiopathogenesis of preterm birth (PTB) is multifactorial, with a universe of risk factors interplaying between the mother and the environment. It is of utmost importance to identify the most informative factors in order to estimate the degree of PTB risk and trace an individualized profile. The aims of the present study were: 1) to identify all acknowledged risk factors for PTB and to select the most informative ones for defining an accurate model of risk prediction; 2) to verify predictive accuracy of the model and 3) to identify group profiles according to the degree of PTB risk based on the most informative factors.

Methods

The Maternal Frailty Inventory (MaFra) was created based on a systematic review of the literature including 174 identified intrauterine (IU) and extrauterine (EU) factors. A sample of 111 pregnant women previously categorized in low or high risk for PTB below 37 weeks, according to ACOG guidelines, underwent the MaFra Inventory. First, univariate logistic regression enabled p-value ordering and the Akaike Information Criterion (AIC) selected the model including the most informative MaFra factors. Second, random forest classifier verified the overall predictive accuracy of the model. Third, fuzzy c-means clustering assigned group membership based on the most informative MaFra factors.

Results

The most informative and parsimonious model selected through AIC included Placenta Previa, Pregnancy Induced Hypertension, Antibiotics, Cervix Length, Physical Exercise, Fetal Growth, Maternal Anxiety, Preeclampsia, Antihypertensives. The random forest classifier including only the most informative IU and EU factors achieved an overall accuracy of 81.08% and an AUC of 0.8122. The cluster analysis identified three groups of typical pregnant women, profiled on the basis of the most informative IU and EU risk factors from a lower to a higher degree of PTB risk, which paralleled time of birth delivery.

Conclusions

This study establishes a generalized methodology for building-up an evidence-based holistic risk assessment for PTB to be used in clinical practice. Relevant and essential factors were selected and were able to provide an accurate estimation of degree of PTB risk based on the most informative constellation of IU and EU factors.

Supplementary Information

The online version contains supplementary material available at (10.1186/s12884-021-03654-3).

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.

Fetal Growth Restriction - Diagnostic Work-up, Management and Delivery

Fetal or intrauterine growth restriction (FGR/IUGR) affects approximately 5 – 8% of all pregnancies and refers to a fetus not exploiting its genetically determined growth potential. Not only a major cause of perinatal morbidity and mortality, it also predisposes these fetuses to the development of chronic disorders in later life. Apart from the timely diagnosis and identification of the causes of FGR, the obstetric challenge primarily entails continued antenatal management with optimum timing of delivery. In order to minimise premature birth morbidity, intensive fetal monitoring aims to prolong the pregnancy and at the same time intervene, i.e. deliver, before the fetus is threatened or harmed. It is important to note that early-onset FGR (< 32 + 0 weeks of gestation [wks]) should be assessed differently than late-onset FGR (≥ 32 + 0 wks). In early-onset FGR progressive deterioration is reflected in abnormal venous Doppler parameters, while in late-onset FGR this manifests primarily in abnormal cerebral Doppler ultrasound. According to our current understanding, the “optimum” approach for monitoring and timing of delivery in early-onset FGR combines computerized CTG with the ductus venosus Doppler, while in late-onset FGR assessment of the cerebral Doppler parameters becomes more important.

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.