Fetal monitoring indications for delivery and 2-year outcome in 310 infants with fetal growth restriction delivered before 32 weeks' gestation in the TRUFFLE study

The role of the PLGF in the prediction of the outcome in pregnancies with a small for gestational age fetus

PURPOSE

To explore the value of measuring maternal serum PLGF in the prediction of the outcome of small for gestational age fetuses (SGA).

METHODS

Singleton pregnancies referred with suspicion of SGA in the third trimester were included if they had: no indication for nor signs of imminent delivery, fetal abdominal circumference (AC) at or below the 10th centile and/or estimated fetal weight (EFW) at or below the 10th centile and/or umbilical artery pulsatility index (Umb-PI) at or above the 90th centile for gestation. Women with pre-eclampsia at presentation were excluded. Maternal blood was drawn at the first (index) visit and analyzed retrospectively.

RESULTS

Fifty-one fetuses were examined. Multiple regression analysis showed that family history of microsomia, index EFW and PLGF were significant predictors of the birthweight centile; index femur length centile and PLGF were significant predictors of pre-eclampsia; PLGF and index systolic blood pressure were significant predictors of iatrogenic preterm delivery < 37 weeks, whereas PLGF and index EFW were significant predictors of birthweight ≤ 5th centile and admission to the neonatal intensive care unit. For all outcomes, the addition of maternal-fetal parameters did not improve the prediction compared to PLGF alone. Using a cutoff of 0.3 MoM for PLGF would identify 94.1% of the pregnancies with iatrogenic preterm delivery and/or intra-uterine death and all of the cases that developed pre-eclampsia, for a screen positive rate of 54.9%. Women with PLGF ≤ 0.3 MoM had a poor fetal/maternal outcome (iatrogenic preterm delivery, pre-eclampsia, intra-uterine death) in 61.5% of cases.

CONCLUSION

In pregnancies complicated by SGA, PLGF identifies a very high-risk group that may benefit from intense surveillance.

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.

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.

Clinical Opinion: The diagnosis and management of suspected fetal growth restriction: an evidence-based approach

This study reviewed the literature about the diagnosis, antepartum surveillance, and time of delivery of fetuses suspected to be small for gestational age or growth restricted. Several guidelines have been issued by major professional organizations, including the International Society of Ultrasound in Obstetrics and Gynecology and the Society for Maternal-Fetal Medicine. The differences in recommendations, in particular about Doppler velocimetry of the ductus venosus and middle cerebral artery, have created confusion among clinicians, and this review has intended to clarify and highlight the available evidence that is pertinent to clinical management. A fetus who is small for gestational age is frequently defined as one with an estimated fetal weight of <10th percentile. This condition has been considered syndromic and has been frequently attributed to fetal growth restriction, a constitutionally small fetus, congenital infections, chromosomal abnormalities, or genetic conditions. Small for gestational age is not synonymous with fetal growth restriction, which is defined by deceleration of fetal growth determined by a change in fetal growth velocity. An abnormal umbilical artery Doppler pulsatility index reflects an increased impedance to flow in the umbilical circulation and is considered to be an indicator of placental disease. The combined finding of an estimated fetal weight of <10th percentile and abnormal umbilical artery Doppler velocimetry has been widely accepted as indicative of fetal growth restriction. Clinical studies have shown that the gestational age at diagnosis can be used to subclassify suspected fetal growth restriction into early and late, depending on whether the condition is diagnosed before or after 32 weeks of gestation. The early type is associated with umbilical artery Doppler abnormalities, whereas the late type is often associated with a low pulsatility index in the middle cerebral artery. A large randomized clinical trial indicated that in the context of early suspected fetal growth restriction, the combination of computerized cardiotocography and fetal ductus venosus Doppler improves outcomes, such that 95% of surviving infants have a normal neurodevelopmental outcome at 2 years of age. A low middle cerebral artery pulsatility index is associated with an adverse perinatal outcome in late fetal growth restriction; however, there is no evidence supporting its use to determine the time of delivery. Nonetheless, an abnormality in middle cerebral artery Doppler could be valuable to increase the surveillance of the fetus at risk. We propose that fetal size, growth rate, uteroplacental Doppler indices, cardiotocography, and maternal conditions (ie, hypertension) according to gestational age are important factors in optimizing the outcome of suspected fetal growth restriction.

Ductus venosus reversed flow in omphalocele: Could it be a prognostic factor for long-term neurological impairment?

Omphalocele (exomphalos) represents one of the most frequent congenital abdominal wall defects. It presents as a defect of inconstant size and is located on the midline, at the base of the umbilical cord, the skin, fascia, and abdominal muscles being absent at this level. Omphaloceles are classified as liver-containing or non-liver-containing, the latter containing primarily bowel loops. We present the case of a 37-year-old pregnant woman with an early diagnosis of liver-containing omphalocele associating ductus venosus reversed flow, with the aim to highlight the importance of the first-trimester morphology scan and to develop a pilot study regarding the neurological development of infants after surgical repair of giant omphaloceles. The particularity of this case consists of a fetus with a positive diagnosis of a giant liver-containing omphalocele but with a small abdominal wall defect during the first-trimester morphology scan at 13 weeks and 3 days of gestation which associated ductus venosus reversed flow, presenting a normal karyotype postabortum. With a small defect, we can speculate the risk of strangling besides the mechanical traction exercised on the ductus venosus generating fetal distress, specifically fetal hypoxia at an early gestational age. In conclusion, the main issue, in this case, was if the fetal omphalocele and ductus venosus reversed flow indicated fetal hypoxia, what was the obstruction effect on the oxygenated blood pathway caused by the abdominal defect, and which were the long-term effects on infants with this complex pathology with an unknown outcome.

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.

Maternal alpha-1-antitrypsin as a noval marker for growth restriction in pre-eclampsia

AIM

To verify the role of maternal serum levels of alpha-1-antitrypsin (AAT), an acute-phase inflammatory protein, as a marker for distinguishing between fetal growth restriction (FGR) and normal birth weight in pre-eclamptic women. We correlate serum AAT levels to the essential feto-maternal parameters for an earlier and cost-benefit diagnostic method, thus distinguishing between FGR and normal birth weight in pre-eclamptic women.

METHODS

An observational study conducted at the University hospital recruited 100 pregnant women in 32/34 weeks of a singleton single tone pregnancy; all were pre-eclampsia cases. All were tested by laboratory and ultrasound examination. Two sets of data were collected; one is maternal parameters such as blood pressure (BP), maternal serum AAT mean platelet volume (MPV), platelet distribution width (PDW), and serum uric acid levels, and the other is fetal parameters such as amniotic fluid index (AFI), fetal weight centile and estimated fetal weight.

RESULTS

A strong negative correlation proved between serum levels of AAT and all study variables except fetal weight (systolic BP, diastolic BP, MPV, PDW, serum uric acid, fetal weight percentile, and AFI) with a correlation coefficient of; -0.95, -0.95, -0.85, -0.93, -0.91, -0.94, and -0.93 respectively. The cut-off value for AAT 0.013 mg/ml showed the highest sensitivity and specificity as a diagnostic marker for FGR. Area under the curve was 0.99.

CONCLUSIONS

Negative correlations between maternal serum AAT and fetal parameters used to assess FGR were confirmed, suggesting that AAT is closely related to the pathophysiology of FGR among pre-eclamptic patients and may serve as a helpful tool in distinguishing between FGR and normal birth weight babies, pending further validation in feto-maternal outcomes.

Brain Sparing Effect on Neurodevelopment in Children with Intrauterine Growth Restriction: A Systematic Review

Background: Fetal growth restriction (FGR) is a pregnancy complication. Multiple studies have connected FGR to poor cognitive development, behavior disorders, and academic difficulties during childhood. Brain sparing has traditionally been defined as an adaptive phenomenon in which the brain obtains the blood flow that it needs. However, this adaptive phenomenon might not have a complete protective effect. This publication aims to systematically review the consequences of brain redistribution on neurodevelopment in children who presented with placental intrauterine growth restriction. Methods: We performed a systematic review according to PRISMA guidelines. It included studies on intrauterine growth restriction or small-for-gestational-age (SGA) fetuses, which middle cerebral artery was measured, and neurodevelopment assessed during childhood. PUBMED and EMBASE databases were searched for relevant published studies. Results: Of the 526 studies reviewed, only 12 were included. Brain sparing was associated with poor cognitive function and lower scores in IQ. Cerebral redistribution was related to better executive function and better behavior at 4 years old but not at 12 years old. Conclusions: We can assume that fetal brain sparing could not be a fully protective phenomenon. We could not find clinical differences in behavioral and executive functions because the results were heterogeneous. Some cognitive abilities could be affected in FGR brain sparing fetuses.

[Management of fetal growth restriction in France: Survey of teaching hospitals and tertiary referral centers]

OBJECTIVES

French Guidelines on Fetal Growth Restriction (FGR) were published in December 2013. It seemed interesting to us to carry out an inventory on the management of FGR in teaching hospitals and tertiary referral centers MATERIAL AND METHODS: We carried out a retrospective survey on the academic year 2020/2021. All teaching hospitals and level III maternity in mainland France were contacted (67). The questionnaire focused on the growth curves used, the etiological assessment carried out, the rate and modalities of antenatal surveillance as well as the criteria indicating a birth.

RESULTS

The response rate was 76%. The CFEF curves are used for screening in 78.4% of centers and in the event of FGR in 39.2% of them. The etiological assessment includes a referent ultrasound in 62.7% of cases and amniocentesis is offered in 74.5% of hospitals in case of severe and early FGR. All centers use umbilical Doppler for FGR. The fetal heart rate is monitored between once a week to three times a day in the event of cerebro-placental redistribution. In case of reverse flow, birth is induced from 28 weeks on for some teams while others continue the pregnancy until 39 weeks. In case of cessation of fetal growth, the expected terms of birth are between 28 and 38 weeks.

CONCLUSION

There is great heterogeneity in the management of FGR, particularly in terms of antenatal surveillance and the term of birth envisaged.

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.

Effects of Antenatal Betamethasone on Fetal Doppler Indices and Short Term Fetal Heart Rate Variation in Early Growth Restricted Fetuses

PURPOSE

 To investigate the effects of the antenatal administration of betamethasone on fetal Doppler and short term fetal heart rate variation (CTG-STV) in early growth restricted (FGR) fetuses.

MATERIALS AND METHODS

 Post hoc analysis of data derived from the TRUFFLE study, a prospective, multicenter, randomized management trial of severe early onset FGR. Repeat Doppler and CTG-STV measurements between the last recording within 48 hours before the first dose of betamethasone (baseline value) and for 10 days after were evaluated. Multilevel analysis was performed to analyze the longitudinal course of the umbilico-cerebral ratio (UC ratio), the ductus venosus pulsatility index (DVPIV) and CTG-STV.

RESULTS

 We included 115 fetuses. A significant increase from baseline in CTG-STV was found on day + 1 (p = 0.019) but no difference thereafter. The DVPIV was not significantly different from baseline in any of the 10 days following the first dose of betamethasone (p = 0.167). Multilevel analysis revealed that, over 10 days, the time elapsed from antenatal administration of betamethasone was significantly associated with a decrease in CTG-STV (p = 0.045) and an increase in the DVPIV (p = 0.001) and UC ratio (p < 0.001).

CONCLUSION

 Although steroid administration in early FGR has a minimal effect on increasing CTG-STV one day afterwards, the effects on Doppler parameters were extremely slight with regression coefficients of small magnitude suggesting no clinical significance, and were most likely related to the deterioration with time in FGR. Hence, arterial and venous Doppler assessment of fetal health remains informative following antenatal steroid administration to accelerate fetal lung maturation.

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).

ACR Appropriateness Criteria® Growth Disturbances-Risk of Fetal Growth Restriction

Fetal growth restriction, or an estimated fetal weight of less than the 10th percentile, is associated with adverse perinatal outcome. Optimizing management for obtaining the most favorable outcome for mother and fetus is largely based on detailed ultrasound findings. Identifying and performing those ultrasound procedures that are most associated with adverse outcome is necessary for proper patient management. Transabdominal ultrasound is the mainstay of initial management and assessment of fetal growth. For those fetuses that are identified as small for gestational age, assessment of fetal well-being with biophysical profile and Doppler velocimetry provide vital information for differentiating those fetuses that may be compromised and may require delivery and those that are well compensated. Delivery of the pregnancy is primarily based upon the gestational age of the pregnancy and the ultrasound findings. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Trends of change in the individual contribution of risk factors for small for gestational age over more than 2 decades

PURPOSE

Over the past years, the prevalence of various risk factors for small for gestational age (SGA) neonates has changed. Little is known if there was also a change in the specific contribution of these risk factors to the prevalence of SGA. We aim to identify trends in the specific contribution of various risk factors for SGA by observing their odds ratios (ORs) throughout different time periods.

METHODS

A nested case-control study was conducted. The ORs for selected known risk factors for SGA occurring in three consecutive 8-year intervals between 1988 and 2014 (T1 - 1988-1996; T2 - 1997-2005; T3 - 2006-2014) were compared. Data were retrieved from the medical centre's computerized perinatal database. Multivariable logistic regression models were constructed and ORs were compared to identify the specific contribution of independent risk factors for SGA along the study period.

RESULTS

During the study period, 285,992 pregnancies met the study's inclusion criteria, of which 15,013 (5.25%) were SGA. Between 1988 and 2014, the incidence of SGA increased from 2.6% in 1988 to 2.9% in 2014. Using logistic regression models, nulliparity, maternal age, gestational age, hypertensive disorders of pregnancy, oligohydramnios and pre-gestational diabetes mellitus were found to be independently associated with SGA. While the adjusted ORs (aOR) of hypertensive disorders of pregnancy and pre-gestational diabetes mellitus had increased, aORs for nulliparity, maternal age and gestational age had remained stable over time. Oligohydramnios had demonstrated a mixed trend of change over the time.

CONCLUSION

In our study, the specific contribution of factors associated with SGA had changed over time. Having a better understating of the changes in the specific contribution of different risk factors for SGA may enable obstetricians to provide consultations.

Etiology and perinatal outcome of periviable fetal growth restriction associated with structural or genetic anomaly

OBJECTIVE

To investigate the etiology and perinatal outcome of periviable fetal growth restriction (FGR) associated with a structural defect or genetic anomaly.

METHODS

This was a retrospective study of singleton pregnancies seen at a referral fetal medicine unit between 2005 and 2018, in which FGR (defined as fetal abdominal circumference ≤ 3^rd percentile for gestational age) was diagnosed between 22 + 0 and 25 + 6 weeks of gestation. The study group included pregnancies with periviable FGR associated with a genetic or structural anomaly (anomalous FGR), while the control group consisted of structurally and genetically normal pregnancies with periviable FGR (non-anomalous FGR). Results of genetic testing, TORCH screen and postmortem examination, as well as perinatal outcome, were investigated.

RESULTS

Of 255 pregnancies complicated by periviable FGR, 188 were eligible; of which 52 (28%) had anomalous FGR and 136 (72%) had non-anomalous FGR. A confirmed genetic abnormality accounted for 17/52 cases (33%) of anomalous FGR, with trisomy 18 constituting over 50% (9/17; 53%). The most common structural defects associated with FGR were central nervous system abnormalities (13/35; 37%). Overall, 12 (23%) cases of anomalous FGR survived the neonatal period. No differences were found in terms of perinatal survival between pregnancies with anomalous and those with non-anomalous FGR.

CONCLUSIONS

Most pregnancies complicated by anomalous FGR were associated with a structural defect. The presence of an associated genetic defect was invariably lethal, while those with a structural defect, in the absence of a confirmed genetic abnormality, survived into infancy in over 90% of cases, with an overall one in three chance of perinatal survival. These data can be used for counseling prospective parents. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Is computerized cardiotocography useful in monochorionic twins with selective intrauterine growth restriction?

Objective: To assess the value of using computerized cardiotocography (cCTG) short-term variation (STV) for intrapartum monitoring in monochorionic twins (MC) complicated by selective intrauterine growth restriction (sIUGR).Material and methods: All available cCTGs retrieved from computerized medical records of MC with sIUGR were retrospectively studied regarding the behavior of the STV. sIUGR was defined as intertwin estimated fetal weight (EFW) discordance of ≥20% with the abdominal circumference (AC) below the fifth percentile and/or the EFW of the smaller twin below the 10th percentile. The sIUGR classification system proposed by Gratacos et al. was used using types I-III on the basis of umbilical artery Doppler characteristics of the IUGR twin. The admission (entry) STV and final pre-delivery (last) STV values were analyzed. Cases with intrauterine demise, with structural or chromosomal abnormalities, with twin anemia polycythemia sequence (TAPS) and/or twin-to-twin transfusion syndrome (TTTS) were excluded.Results: During the study period, 64 consecutive cases were managed within our department. Thirty-two cases fulfilled the inclusion criteria for analysis. Mean gestational age at assessment and at delivery was 28.4 ± 2.7 and 31.5 ± 2.2 weeks, respectively. The entry STV and last STV before delivery were not statistically different (mean IUGR STV entry: 9.3 ± 3.4 ms versus last 8 ± 2.2 ms; p = .051; mean co-twin STV entry: 9.1 ± 2.8 ms versus last 9.2 ± 3 ms; p = .87). Neither was the sIUGR-type adjusted STV.Conclusions: In MC pregnancies complicated by sIUGR, the cCTG STV does not distinguish between fetuses, nor does it show differences in cases of fetal deterioration monitored by conventional CTG.

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

OBJECTIVE

To explore the effect on perinatal outcome of different fetal monitoring strategies for early-onset fetal growth restriction (FGR).

METHODS

This was a cohort analysis of individual participant data from two European multicenter trials of fetal monitoring methods for FGR: the Growth Restriction Intervention Study (GRIT) and the Trial of Umbilical and Fetal Flow in Europe (TRUFFLE). All women from GRIT (n = 238) and TRUFFLE (n = 503) who were randomized between 26 and 32 weeks' gestation were included. The women were grouped according to intervention and monitoring method: immediate delivery (GRIT) or delayed delivery with monitoring by conventional cardiotocography (CTG) (GRIT), computerized CTG (cCTG) only (GRIT and TRUFFLE) or cCTG and ductus venosus (DV) Doppler (TRUFFLE). The primary outcome was survival without neurodevelopmental impairment at 2 years of age.

RESULTS

Gestational age at delivery and birth weight were similar in both studies. Fetal death rate was similar between the GRIT and TRUFFLE groups, but neonatal and late death were more frequent in GRIT (18% vs 6%; P < 0.01). The rate of survival without impairment at 2 years was lowest in pregnancies that underwent immediate delivery (70% (95% CI, 61-78%)) or delayed delivery with monitoring by CTG (69% (95% CI, 57-82%)), increased in those monitored using cCTG only in both GRIT (80% (95% CI, 68-91%)) and TRUFFLE (77% (95% CI, 70-84%)), and was highest in pregnancies monitored using cCTG and DV Doppler (84% (95% CI, 80-89%)) (P < 0.01 for trend).

CONCLUSIONS

This analysis supports the hypothesis that the optimal method for fetal monitoring in pregnancies complicated by early-onset FGR is a combination of cCTG and DV Doppler assessment.

TRIAL REGISTRATION

GRIT ISRCTN41358726 and TRUFFLE ISRCTN56204499. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

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.

The controversial role of the ductus venosus in hypoxic human fetuses

The ductus venosus plays a critical role in circulatory adaptation to hypoxia in fetal growth restriction but the mechanisms still remain controversial. Increased shunting of blood through the ductus venosus under hypoxic conditions has been shown in animal and human studies. The hemodynamic laws governing the accelerated flow in this vessel suggest that any dilation at its isthmus, which increases the blood flow shunting to the heart, is associated with a low, absent or reversed a-wave and a high pulsatility index. Cardiac dysfunction associated with increased atrial pressure as well as reduced ventricular compliance might be predominant mechanisms determining the profile of ductus venosus velocity waveforms in severe fetal growth restriction with signs of hypoxic compromise. Understanding the pathophysiology of the ductus venosus will underpin translation of the hypotheses developed through biostatistics toward explaining with more confidence Doppler changes in the fetal circulation in predicting clinical outcomes.

Knowledge Gaps and Emerging Research Areas in Intrauterine Growth Restriction-Associated Brain Injury

Intrauterine growth restriction (IUGR) is a complex global healthcare issue. Concerted research and clinical efforts have improved our knowledge of the neurodevelopmental sequelae of IUGR which has raised the profile of this complex problem. Nevertheless, there is still a lack of therapies to prevent the substantial rates of fetal demise or the constellation of permanent neurological deficits that arise from IUGR. The purpose of this article is to highlight the clinical and translational gaps in our knowledge that hamper our collective efforts to improve the neurological sequelae of IUGR. Also, we draw attention to cutting-edge tools and techniques that can provide novel insights into this disorder, and technologies that offer the potential for better drug design and delivery. We cover topics including: how we can improve our use of crib-side monitoring options, what we still need to know about inflammation in IUGR, the necessity for more human post-mortem studies, lessons from improved integrated histology-imaging analyses regarding the cell-specific nature of magnetic resonance imaging (MRI) signals, options to improve risk stratification with genomic analysis, and treatments mediated by nanoparticle delivery which are designed to modify specific cell functions.

The relationship between the placental serotonin pathway and fetal growth restriction

Fetal growth restriction (FGR) is a complex disorder of human pregnancy that leads to poor health outcomes in offspring. These range from immediate risks such as perinatal morbidity and stillbirths, to long-term complications including severe neurodevelopmental problems. Despite its relatively high global prevalence, the aetiology of FGR and its complications is not currently well understood. We now know that serotonin (5-HT) is synthesised in the placenta and is crucial for early fetal forebrain development in mice. However, the contribution of a disrupted placental 5-HT synthetic pathway to the pathophysiology of placental insufficiency in FGR and its significant fetal neurodevelopmental complications are unclear.

Outcome in early-onset fetal growth restriction is best combining computerized fetal heart rate analysis with ductus venosus Doppler: insights from the Trial of Umbilical and Fetal Flow in Europe

BACKGROUND

Early-onset fetal growth restriction represents a particular dilemma in clinical management balancing the risk of iatrogenic prematurity with waiting for the fetus to gain more maturity, while being exposed to the risk of intrauterine death or the sequelae of acidosis.

OBJECTIVE

The Trial of Umbilical and Fetal Flow in Europe was a European, multicenter, randomized trial aimed to determine according to which criteria delivery should be triggered in early fetal growth restriction. We present the key findings of the primary and secondary analyses.

STUDY DESIGN

Women with fetal abdominal circumference <10th percentile and umbilical pulsatility index >95th percentile between 26-32 weeks were randomized to 1 of 3 monitoring and delivery protocols. These were: fetal heart rate variability based on computerized cardiotocography; and early or late ductus venosus Doppler changes. A safety net based on fetal heart rate abnormalities or umbilical Doppler changes mandated delivery irrespective of randomized group. The primary outcome was normal neurodevelopmental outcome at 2 years.

RESULTS

Among 511 women randomized, 362/503 (72%) had associated hypertensive conditions. In all, 463/503 (92%) of fetuses survived and cerebral palsy occurred in 6/443 (1%) with known outcome. Among all women there was no difference in outcome based on randomized group; however, of survivors, significantly more fetuses randomized to the late ductus venosus group had a normal outcome (133/144; 95%) than those randomized to computerized cardiotocography alone (111/131; 85%). In 118/310 (38%) of babies delivered <32 weeks, the indication was safety-net criteria: 55/106 (52%) in late ductus venosus, 37/99 (37%) in early ductus venosus, and 26/105 (25%) in computerized cardiotocography groups. Higher middle cerebral artery impedance adjusted for gestation was associated with neonatal survival without severe morbidity (odds ratio, 1.24; 95% confidence interval, 1.02-1.52) and infant survival without neurodevelopmental impairment at 2 years (odds ratio, 1.33; 95% confidence interval, 1.03-1.72) although birthweight and gestational age were more important determinants.

CONCLUSION

Perinatal and 2-year outcome was better than expected in all randomized groups. Among survivors, 2-year neurodevelopmental outcome was best in those randomized to delivery based on late ductus venosus changes. Given a high rate of delivery based on the safety-net criteria, deciding delivery based on late ductus venosus changes and abnormal computerized fetal heart rate variability seems prudent. There is no rationale for delivery based on cerebral Doppler changes alone. Of note, most women with early-onset fetal growth restriction develop hypertension.

Fetal growth restriction: current knowledge

BACKGROUND

Fetal growth restriction (FGR) is a condition that affects 5-10% of pregnancies and is the second most common cause of perinatal mortality. This review presents the most recent knowledge on FGR and focuses on the etiology, classification, prediction, diagnosis, and management of the condition, as well as on its neurological complications.

METHODS

The Pubmed, SCOPUS, and Embase databases were searched using the term "fetal growth restriction".

RESULTS

Fetal growth restriction (FGR) may be classified as early or late depending on the time of diagnosis. Early FGR (<32 weeks) is associated with substantial alterations in placental implantation with elevated hypoxia, which requires cardiovascular adaptation. Perinatal morbidity and mortality rates are high. Late FGR (≥32 weeks) presents with slight deficiencies in placentation, which leads to mild hypoxia and requires little cardiovascular adaptation. Perinatal morbidity and mortality rates are lower. The diagnosis of FGR may be clinical; however, an arterial and venous Doppler ultrasound examination is essential for diagnosis and follow-up. There are currently no treatments to control FGR; the time at which pregnancy is interrupted is of vital importance for protecting both the mother and fetus.

CONCLUSION

Early diagnosis of FGR is very important, because it enables the identification of the etiology of the condition and adequate monitoring of the fetal status, thereby minimizing risks of premature birth and intrauterine hypoxia.