Fetal Medicine Foundation reference ranges for umbilical artery and middle cerebral artery pulsatility index and cerebroplacental ratio

Role of myocardial performance index (MPI) and cerebro-placental ratio (CPR) in predicting adverse perinatal outcome

INTRODUCTION

This study aimed to evaluate the association of the Myocardial Performance Index (MPI) and Cerebro-Placental Ratio (CPR) in predicting adverse perinatal outcomes in fetuses who are appropriately-grown (AGA), small-for-gestational-age (SGA) and growth restricted (FGR).

METHODS

Singleton pregnancies were recruited after 24 weeks. The patients were recruited after having been classified as AGA (AC/EFW > 10th centile), SGA (AC/EFW-3rd-10th centile without doppler abnormalities), and FGR (AC/EFW < 3rd centile or 3rd-10th centile with doppler abnormalities). A total of 103 cases comprising 48 AGA, 11 SGA, and 44 FGRfetuses were recruited. The Pulsatility Index of the Umbilical artery, Middle cerebral artery, Ductus Venosus, and Aortic Isthmus was obtained. MPI and CPR were calculated too. The primary outcome was to evaluate the predictive value of MPI and CPR for the composite adverse perinatal outcome.

RESULTS

The mean gestational age of recruitment was 30 weeks. The OR for Composite Adverse Perinatal Outcome in FGR group for MPI > .47 and CPR < 1.67 was 3.48 (95% CI: 1.00-12.24, p-value < .05) with sensitivity and specificity of 65% each and 11.08 (95% CI: 2.62-46.83, p-value = .001) with the sensitivity of 82% and specificity of 70%, respectively. When combined together, MPI and CPR yielded an OR of 58.5 (95% CI: 4.58-746.57, p-value = .002) with a sensitivity of 56.5% and specificity of 95% in the FGR group.

CONCLUSIONS

MPI in conjunction with CPR can be used together to predict adverse perinatal outcomes in FGR.

Frontal lobe development in fetuses with growth restriction by using ultrasound: a case-control study

BACKGROUND

Fetal growth restriction (FGR) occurs in up to 10% of pregnancies and is a leading cause of perinatal mortality and neonatal morbidity. Three-dimensional ultrasonography of intracranial structure volume revealed significant differences between fetuses with FGR and appropriate for gestational age (AGA) fetuses. We aimed to compare the frontal lobe development between fetuses with FGR and appropriately grown fetuses and evaluate the impact of fetal circulatory redistribution (FCR) on frontal lobe development in fetuses with FGR.

METHODS

We performed a case-control study at our institution from August 2020 to April 2021. The frontal antero-posterior diameter (FAPD) and occipito-frontal diameter (OFD) were measured on the trans-ventricle view and we calculated the Z-scores for FAPD and OFD standardized for gestational age (GA) and transverse cerebellar diameter (TCD) by performing a standard regression analysis followed by weighted regression of absolute residual values in appropriately grown fetuses. We calculated the FAPD/OFD ratio as 100 × FAPD/OFD and FAPD/HC (head circumference) as 100 × FAPD/HC. To compare intracranial parameters, we randomly selected a control group of appropriately grown fetuses matched with the FGR group at the time of ultrasonography. We performed between-group comparisons of the FAPD Z-score, OFD Z-score, FAPD/OFD ratio and FAPD/HC. Similarly, we compared intracranial parameters between fetuses with FGR with and without FCR.

RESULTS

FAPD/OFD ratio was curvilinear related to all the independent variables (GA, BPD, FL, and TCD). Compared with appropriately grown fetuses, fetuses with FGR showed a significantly lower FAPD/OFD ratio, FAPD Z-score, and FAPD/HC. There was no significant difference in the FAPD Z-score, FAPD/OFD ratio, and FAPD/HC between FGR fetuses with and without FCR.

CONCLUSIONS

The FAPD/OFD ratio varied during pregnancy, with a mild reduction before and a mild increase after about 33 gestational weeks. Fetuses with FGR showed reduced frontal lobe growth; moreover, fetal frontal lobe development disorders were not significantly different in fetuses with FCR.

TRIAL REGISTRATION

Date: 09-27-2017; Number: [2017]239.

Maternal hemodynamics for the identification of early fetal growth restriction in normotensive pregnancies

We aimed at testing systemic vascular resistance (SVR) for the correct identification of early fetal growth restriction (FGR). 61 normotensive patients, gestational age 29 + 0-32 + 0, with suspected diagnosis of early FGR, were submitted to USCOM and to an ultrasound evaluation. 24 patients met the criteria of FGR, and 9 patients developed umbilical artery Doppler alterations. SVR>1006 dyn s·cm^-5 correctly identified patients with a subsequent diagnosis of FGR, whereas SVR>1222 dyn s·cm^-5 was related to FGR with subsequent umbilical artery Doppler alterations. These data might be important to introduce USCOM in the clinical practice to identify and treat FGR.

Fetal Doppler Echocardiographic Assessment Predicts Severe Postnatal Obstruction in Total Anomalous Pulmonary Venous Connection

BACKGROUND

Obstructed total anomalous pulmonary venous connection (TAPVC) is a form of critical congenital heart disease that usually requires urgent postnatal intervention. Knowing which patients have severe obstruction can aid delivery planning. The authors previously developed a novel quantitative metric of pulmonary venous flow, the pulmonary venous variability index (PVVI). The aim of this study was to test the hypothesis that fetal PVVI and vertical vein Doppler velocities are associated with severe pulmonary vein obstruction postnatally.

METHODS

A retrospective cohort study of neonates with prenatally diagnosed TAPVC was performed. Patients who underwent fetal echocardiography at the Children's Hospital of Philadelphia with Doppler interrogation of the vertical vein were included for analysis. Twenty-nine patients met criteria (21 with heterotaxy, 18 with supracardiac TAPVC). The latest gestation fetal echocardiogram was used. Severe pulmonary vein obstruction was defined as preoperative death or urgent surgery or catheter-based intervention (first day of life). Measurements of PVVI, defined as (maximum velocity - minimum velocity)/mean velocity, were made offline. Wilcoxon rank sum models were used to assess the associations of severe obstruction and PVVI and maximum, mean, and minimum velocities.

RESULTS

The mean gestational age at the latest fetal echocardiographic examination was 35 weeks (range, 30-39 weeks). Twelve of the 29 patients (41%) met criteria for severe pulmonary vein obstruction. Lower PVVI was associated with greater risk for severe pulmonary venous obstruction (P = .008). The maximum, mean, and minimum velocities in the vertical vein were all significantly associated with severe pulmonary venous obstruction (P = .03, P = .03, and P = .007, respectively). Qualitative assessment of obstruction was not significantly associated with the outcome. Interobserver reliability for all vertical vein Doppler metrics was high (intraclass correlation coefficient > 0.9).

CONCLUSIONS

Fetal PVVI and maximum, mean, and minimum velocities are associated with severe postnatal pulmonary vein obstruction in TAPVC. Accurate prediction of obstructed TAPVC could allow safer delivery planning. Further research with larger sample sizes is needed to identify the ideal cutoff values for these Doppler measures.

Middle cerebral artery to uterine artery pulsatility index ratios in pregnancy with fetal growth restriction regarding negative perinatal outcomes

Background/Aim: Fetal growth restriction (FGR) causes a high risk of perinatal morbidity and mortality, and the timing of the correct delivery time decision remains controversial. Cerebroplacental ratio (CPR), umbilical artery, uterine artery (UA) and middle cerebral artery (MCA) Doppler studies are used to predict adverse perinatal outcomes in FGR. However, since there is insufficient reliability for each separately and together, the search for new methods continues. This retrospective study was conducted to determine the degree of neonatal morbidity in fetuses suspected of having FGR by evaluating the MCA to UA pulsatility index (PI) ratios together with frequently used Doppler examinations. Methods: This was a retrospective cohort study conducted in a single-center hospital with the approval of the Medical Institutional Ethics Committee. A total of 424 pregnant women admitted to a tertiary hospital and diagnosed with FGR between July 2020 and December 2021 who were informed and approved were included in the study. Gestational age was confirmed by first trimester sonographic measurements of pregnancy. All pregnant women were examined by Doppler USG and umbilical artery, mean UA, fetal MCA, ductus venosus, CPR (MCA/umbilical artery pulsatility index ratio) and cerebrouterine ratio (MCA/UA) PI values were measured. Negative perinatal outcomes were recorded as blood gas level of the newborn at 7.2 and below, Apgar score of 7 and below at the fifth minute, and needing neonatal intensive care (NICU). Adverse perinatal and postnatal outcomes were recorded and compared with Doppler findings. If there were no signs of a negative perinatal outcome, it was considered a positive outcome. If at least one of the symptoms of adverse perinatal outcomes was present, it was considered a negative outcome Results: Decreased CPR and decreased MCA to UA PI were significantly and positively associated with an increased likelihood of exhibiting negative perinatal outcomes in pregnancies with FGR (P < 0.001, P < 0.001, respectively). The receiver operating characteristic (ROC) curve analysis showed that the optimal cut-off value for MCA to uterine artery PI was 1.41 to predict FGR with 57.37% sensitivity and 62.50% specificity (AUC: 0.629; 95% CI: 0.581–0.675). When the CPR cut-off value was taken as 1.2069, the sensitivity was 42.86% and the specificity 83.93% in predicting negative perinatal outcomes in CPR values below this value (P < 0.001). Conclusion: CPR is the most successful criterion in distinguishing between positive and negative perinatal outcomes. It has been demonstrated that the MCA to uterine artery PI ratio values after CPR can also be used for this distinction. MCA to UA PI ratio sensitivity was higher than CPR and umbilical artery. This situation shows that MCA to uterine artery PI ratio (alone or when evaluated together with PPV and NPV ratios) is a criterion that can be added to other Doppler examinations in predicting negative perinatal outcomes.

Role of the cerebro-placental-uterine ratio in predicting adverse perinatal outcome in low-risk pregnancies at term

PURPOSE

The cerebroplacental ratio (CPR) is associated with adverse perinatal outcome (APO) in low-risk pregnancies near term. A Doppler parameter, which also includes information from the uterine vessels could potentially improve detection of subclinical placental dysfunction. The aim of this study is to investigate the performance of cerebro-placental-uterine ratio (CPUR) related to APO prediction in low-risk term pregnancies in > 40 + 0 weeks.

METHODS

This is a retrospective cohort study. All low-risk pregnancies in which feto-maternal Doppler was examined from 40 + 0 weeks and an appropriate for gestational age fetus was present were included. ROC (receiver operating characteristic curves) analyses were performed to assess the predictive value of CPUR. The presence of at least one of the following outcome parameters was defined as composite APO (CAPO): operative delivery (OD) due to intrapartum fetal compromise (IFC), admission to the neonatal intensive care unit, umbilical cord arterial pH ≤ 7.15, 5 min APGAR ≤ 7.

RESULTS

A total of n = 114 cases were included. Mean gestational age at examination and delivery were 40 + 3 weeks and 40 + 6 weeks, respectively. Overall, CAPO occurred in 38 of 114 cases (33.3%). ROC analyses showed a significant association of CPUR (AUC = 0.67, p = 0.004) and CPR (AUC = 0.68, p = 0.002) with CAPO. Additionally, CPUR (AUC = 0.64, p = 0.040) showed a predictive value for OD due to IFC.

CONCLUSION

The CPUR in > 40 + 0 weeks showed a predictive value for CAPO and OD due to IFC in low-risk pregnancies. However, the extent to which CPUR can be used to optimize delivery management warrants further investigations in prospective interventional studies.

Intrauterine cannabis exposure and fetal and maternal blood flow: a case-control study

INTRODUCTION

Cannabis consumption during pregnancy increases the risk of pregnancy and neonatal complications. Since the underlying mechanism is unknown, the purpose of this study is to evaluate the changes in maternal and fetal blood flow in pregnancies exposed to cannabis, Δ9-tetrahydrocannabinol (THC).

MATERIAL AND METHODS

A case-control study between 2013 and 2020, included women with continued cannabis exposure during the pregnancies, defined by qualitative detection of THC in urine (Cannabis Group), and low-risk pregnancy women divided into tobacco smokers (Tobacco Group), and non-tobacco smokers (Control Group). We evaluated the association between cannabis consumption and maternal and fetal blood flow parameters measured by Doppler ultrasound: uterine artery at 11-14, 20-22 and 33-35 weeks, umbilical artery and middle cerebral artery at 33-35 weeks. Cerebral-placental ratio was calculated.

RESULTS

Overall, 275 participants were included, 60 in the Cannabis Group, 17 in the Tobacco Group and 198 in the Control Group. At 33-35 weeks, differences were found in the umbilical artery pulsatility index (PI) (1.05 ± 0.23, 1.06 ± 0.19, 0.93 ± 0.15, P < 0.01), middle cerebral artery PI (1.75 ± 0.35, 1.90 ± 0.45, 1.88 ± 0.34, P < 0.05), cerebral-placental ratio (1.69 ± 0.40, 1.85 ± 0.53, 2.07 ± 0.47, P < 0.05) and mean uterine artery PI (0.89 ± 0.26, 0.73 ± 0.19, 0.74 ± 0.20, P < 0.01), respectively. On logistic regression analysis, adjusted for maternal age, maternal body mass index, maternal weight and white ethnicity, both cannabis and tobacco were predictors for increased umbilical artery PI, but only cannabis was a predictor for a decreased cerebral-placental ratio and an increased uterine artery PI at 33-35 weeks.

CONCLUSIONS

Data from a large cohort of continuous cannabis exposure pregnancies show that cannabis is associated with maternal and fetal blood flow changes. However, it is not possible to disentangle the association of the tobacco and cannabis.

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.

Evaluation of the selected parameters of the fetal diastolic functions in normally grown or macrosomic fetuses of gestational diabetic mothers with poor glycaemic control

OBJECTIVE

This study aimed to investigate whether the third trimester fetal cardiac diastolic function measured by selected conventional Doppler indices is affected in appropriate-for-gestational-age or macrosomic fetuses of gestational diabetic mothers with poor glycaemic control.

METHODS

This cross-sectional study included 93 pregnant women divided into two groups. Group 1 included 45 appropriate-for-gestational-age or macrosomic fetuses from gestational diabetic mothers with poor glycaemic control (study group). Group 2 included 48 appropriate-for-gestational-age fetuses from gestational age-matched healthy mothers (control group). Functional fetal cardiac parameters and fetoplacental Doppler parameters were measured. Data were compared between the two groups.

RESULTS

Maternal characteristics did not differ significantly between the study and the control group. There were no significant differences in the early and late velocity, early/late velocity ratio of both mitral and tricuspid valves, the fetal pulmonary vein pulsatility index, and the ductus venosus pulsatility index between the study and the control group. Moreover, the rate of abnormal Doppler findings in pulmonary vein (pulmonary vein pulsatility index >95th centile), ductus venosus (ductus venosus pulsatility index >95th centile), and peripheral vessels (umbilical artery pulsatility index >95th centile, middle cerebral artery pulsatility index <5th centile, cerebra-placental index >95th centile) were comparable in both groups.

CONCLUSIONS

The third trimester fetal diastolic functions measured by selected conventional Doppler techniques do not seem to be altered in appropriate-for-gestational-age or macrosomic fetuses of gestational diabetic mothers who have poor glycaemic control.

Near-Term Cerebroplacental Doppler, Heart Morphology, and Neonatal Biometry in Hypoplastic Left Heart Syndrome

OBJECTIVES

To analyze near-term cerebroplacental Doppler, heart morphology, and neonatal biometry in isolated hypoplastic left heart syndrome (HLHS) relative to healthy controls.

METHODS

This retrospective study included 55 fetuses with HLHS (29 with mitral valve stenosis [MS]/aortic valve atresia [AA], 14 with MS/aortic valve stenosis, and 12 with mitral valve atresia [MA]/[AA]) diagnosed prenatally between 2010 and 2019 at 2 referral centers and 101 healthy controls. Ultrasound assessment included umbilical artery (UA), middle cerebral artery (MCA) pulsatility index (PI), and cerebroplacental ratio (CPR), with neonatal weight, length, head circumference (HC), Apgar score, and UA pH measured at birth.

RESULTS

In total, 32.7% of HLHS fetuses had abnormal MCA-PI and UA-PI, and 38.2% had CPRs below the fifth percentile before birth. All tested Doppler parameters differed from those of the healthy controls (P ≤ .01). Birth weight and length were comparable between HLHS and control fetuses, whereas birth HCs were smaller in the HLHS group than in the control group (P = .018). In both groups, increased UA-PI correlated with lower birth weight, but only HLHS fetuses with UA-PI > the 95th percentile had a lower median HC at birth than those with normal UA-PI (P = .045). The median UA-PI percentile was higher in fetuses with MA than in fetuses with MS (P = .015). The ascending aortic diameter correlated with birth weight (P = .036) and birth length (P = .039).

CONCLUSION

Abnormal cerebroplacental hemodynamics are evident in a high percentage of near-term fetuses with HLHS, and increased placental resistance may contribute to birth weight and HC. Moreover, heart morphology may impact placental circulation and neonatal biometry.

Ultrasound predictors of adverse outcome in pregnancy complicated by pre-existing and gestational diabetes

INTRODUCTION

Ultrasound assessment of fetuses subjected to hyperglycemia is recommended but, apart from increased size, little is known about its interpretation, and the identification of which large fetuses of diabetic pregnancy are at risk is unclear. Newer markers of adverse outcomes, abdominal circumference growth velocity and cerebro-placental ratio, help to predict risk in non-diabetic pregnancy. Our study aims to assess their role in pregnancies complicated by diabetes.

MATERIAL AND METHODS

This is a retrospective analysis of a cohort of singleton, non-anomalous fetuses of women with pre-existing or gestational diabetes mellitus, and estimated fetal weight at the 10th centile or above. Gestational diabetes was diagnosed by selective screening of at risk groups. A universal ultrasound scan was offered at 20 and 36 weeks of gestation. Estimated fetal weight, abdominal circumference growth velocity, presence of polyhydramnios, and cerebro-placental ratio were evaluated at the 36-week scan. A composite adverse outcome was defined as the presence of one or more of perinatal death, arterial cord pH less than 7.1, admission to Neonatal Unit, 5-minute Apgar less than 7, severe hypoglycemia, or cesarean section for fetal compromise. A chi-squared test was used to test the association of estimated fetal weight at the 90th centile or above, polyhydramnios, abdominal circumference growth velocity at the 90th centile or above, and cerebro-placental ratio at the 5th centile or below with the composite outcome. Logistic regression was used to assess which ultrasound markers were independent risk factors. Odds ratios of composite adverse outcome with combinations of independent ultrasound markers were calculated.

RESULTS

A total of 1044 pregnancies were included, comprising 87 women with pre-existing diabetes mellitus and 957 with gestational diabetes. Estimated fetal weight at the 90th centile or above, abdominal circumference growth velocity at the 90th centile or above, cerebro-placental ratio at the 5th centile or below, but not polyhydramnios, were significantly associated with adverse outcomes: odds ratios (95% confidence intervals) 1.85 (1.21-2.84), 1.54 (1.02-2.31), 1.92 (1.21-3.30), and 1.53 (0.79-2.99), respectively. Only estimated fetal weight at the 90th centile or above and cerebro-placental ratio at the 5th centile or below were independent risk factors. The greatest risk (odds ratio 6.85, 95% confidence interval 2.06-22.78) was found where both the estimated fetal weight is at the 90th centile or above and the cerebro-placental ratio is at the 5th centile or below.

CONCLUSIONS

In diabetic pregnancies, a low cerebro-placental ratio, particularly in a macrosomic fetus, confers additional risk.

Cerebroplacental Ratio Versus Nonstress Test in Predicting Adverse Perinatal Outcomes in Hypertensive Disorders of Pregnancy: A Prospective Observational Study

Introduction: In developing countries, nonstress test (NST) is the most widely used method for antenatal fetal surveillance.Lately, cerebroplacental ratio (CPR) has emerged as a predictor for adverse perinatal outcomes, especially in hypertensive disorders in pregnancy (HDP). Against this background, the present study was conducted with the primary objective of quantifying the diagnostic accuracy of cerebroplacental ratio (CPR) versus nonstress test (NST) in predicting adverse perinatal outcomes in women with HDP.

Methods: This was a prospective observational cohort study conducted in a tertiary care institute in eastern India. All consecutive women with hypertension in pregnancy at a gestational age of ≥32 weeks were recruited into the study. Both CPR and NST were performed at baseline and repeated weekly till delivery. The parameters obtained within one week of delivery were entered for analysis.

Results: Sixty-two of the 65 women completed the study. There were 22 women (35.5%) in group A (both CPR and NST normal), 17 (27.4%) in group B (CPR abnormal, NST normal), 14 (22.6%) in group C (CPR normal and NST abnormal), and nine (14.5%) in group D (both CPR and NST abnormal). CPR had greater sensitivity (93.33% versus 46.67%), with higher positive predictive value (53.85% versus 30.43%), specificity (74.47% versus 65.91%), and negative predictive value (97.22% versus 79.49%) than NST for predicting neonatal intensive care unit admission. CPR also had higher sensitivity (84.62% versus 61.54%) and specificity (91.34% versus 69.39%) than NST in predicting neonatal complications. The negative predictive value (NPV) of CPR was 100% for predicting requirement of bag and mask ventilation and continuous positive airway pressure.

Conclusion: CPR had greater diagnostic accuracy in terms of both higher sensitivity and greater specificity than NST in predicting adverse perinatal outcomes in women with hypertensive disorders of pregnancy.

Fetal and Neonatal Middle Cerebral Artery Hemodynamic Changes and Significance under Ultrasound Detection in Hypertensive Disorder Complicating Pregnancy Patients with Different Severities

Colour Doppler ultrasound was applied for monitoring the hemodynamic parameters of fetal uterine artery (UtA), umbilical artery (UA), and middle cerebral artery (MCA) during pregnancy. In hypertension disease complicating pregnancy, these hemodynamic measures and their therapeutic applicability value were reviewed (HDCP). 120 singleton pregnant women were chosen, with 40 cases of mild preeclampsia (mild group), 40 cases of severe preeclampsia (severe group), and 40 normal control pregnant women (control group). The hemodynamic parameters of UtA, MCA, and UA were monitored in the three groups, including pulsatility index (PI), resistance index (RI), and the systolic/diastolic velocity (S/D). The parameters PI, RI, S/D, and venous catheter shunt rate (Qdv/Quv) of UtA and UA in the severe group were higher than those in the normal group and the mild group, showing the differences statistically significant ( $P<0.05$ ). The PI, RI, and S/D of MCA in the severe group were lower than those in the normal group and the mild group ( $P<0.05$ ). The changing trends of PI, RI, and S/D in the severe group were all first increased and then decreased in the early, middle, and later pregnancy ( $P<0.05$ ). The area under the curve (AUC) was 0.98 in the receiver operating characteristic (ROC) curve created using a combination of hemodynamic measures and pregnancy outcomes, and the sensitivity and specificity for predicting bad outcomes were 94.7 percent and 96.4 percent, respectively. Colour Doppler ultrasound may accurately detect changes in the PI, RI, and S/D of UtA, MCA, and UA in pregnant women and serve as a reference for determining the intrauterine state of the fetuses and predicting bad pregnancy outcomes. In particular, the parameters in later pregnancy were higher worthy of diagnostic value for adverse pregnancy outcomes. The combination of various parameters could make an improvement of the diagnostic accuracy and provide a basis for guiding treatment as well as determining the optimal timing of delivery.

Prenatal Prediction of Fetal Growth Restriction and Postnatal Outcomes by Ultrasound Assessment of Fetal Myocardial Performance Index and Blood Flow Spectrum

Objective

Fetal growth restriction (FGR) affects 5% to 10% of newborns and is a major determinant of perinatal morbidity and mortality. Myocardial performance index (MPI), also known as the Tei index, is a useful, noninvasive, and Doppler-derived myocardial performance tool for fetal cardiac function evaluation. The purpose of the study is to evaluate ultrasonic prediction on FGR and postnatal outcomes using MPI and blood flow spectrum.

Methods

This retrospective study included 240 pregnant women developing FGR and 240 healthy pregnant women. The blood flow spectrum of middle cerebral artery (MCA), umbilical artery (UA), and ductus venous including systolic to diastolic ratio (S/D), resistant index (RI), pulse index (PI), and peak ventricular systolic velocity/atrial contraction valley velocity (S/a) were examined using the GE Voluson E8 ultrasound system.

Results

The MPI, S/D, RI, PI of UA, and S/a were all higher but S/D, RI, and PI of MCA were lower in the FGR group than those in the control group (P < 0.001). The MPI, S/D, RI, PI of UA, S/D, RI, PI of MCA, and ductus venous S/a yielded AUC of 0.813, 0.835, 0.791, 0.804, 0.789, 0.796, 0.803, and 0.784 when they were used to predict the incidence of FGR. Of note, the pregnant women with poor pregnancy outcomes exhibited higher values of MPI, S/D, RI, PI of UA, and S/a with lower scores of 1 min Apgar concomitant with lower values regarding S/D, RI, and PI of MCA than those with favorable pregnancy outcomes (P < 0.001). The MPI (r = -0.623), S/D (r = -0.660), RI (r = -0.601), PI (r = -630) of UA, and S/a (r = -0.573) shared negative correlations with 1 min Apgar scores (P < 0.001). Of note, the S/D (r = 0.562), RI (r = 0.597), and PI (r = 0.619) of MCA were positively correlated with 1 min Apgar scores (P < 0.001). It was revealed that the MPI, S/D, RI, PI of UA, S/D, RI, PI of MCA, and ductus venous S/a yielded AUC of 0.806, 0.833, 0.774, 0.788, 0.807, 0.729, 0.748, and 0.770 when they were used to predict the incidence of poor pregnancy outcomes for pregnant women developing FGR.

Conclusion

Our study demonstrates good ultrasonic prediction on FGR and postnatal outcomes using MPI and blood flow spectrum.

Evaluating the predictive value of fetal Doppler indices and neonatal outcome in late-onset preeclampsia with severe features: a cross-sectional study in a resource-limited setting

Background

Preeclampsia constitutes a major health problem with substantial maternal and perinatal morbidity and mortality. The aim of this study was to detect the diagnostic efficacy of fetal Doppler in predicting adverse outcomes in severe late onset preeclampsia (LOP).

Methods

A prospective study was conducted among childbearing women who presented with severe LOP and matched controls. Umbilical artery (UA) and middle cerebral artery (MCA) Doppler indices including pulsatility index (PI), resistance index (RI), systolic/diastolic ratio (S/D) and cerebroplacental ratio (CPR) were measured.

Results

All UA indices were significantly higher in the case group compared to the controls (p < 0.001). UA PI and RI were significantly correlated with all neonatal adverse outcomes except cord pH status (p < 0.05). Abnormal CPR was the most sensitive index that positively correlated with intrauterine growth retardation (IUGR), low 5- minute Apgar score and neonatal intensive care unit admission (79, 72.8 and 73.3%, respectively). In the same context, Abnormal UA PI and RI represented the most specific tool for predicting IUGR, low 1- and 5- minutes Apgar score with positive predictive values were 52, 87 and 57%, respectively.

Conclusion

In severe LOP, UA Doppler remains the preferential indicator for adverse birth outcomes with CPR is the best index that could be solely used for predicting such outcome.

Role of placental, fetal and maternal cardiovascular markers in predicting adverse outcome in women with suspected or confirmed pre-eclampsia

OBJECTIVE

To assess the performance of placental, fetal and maternal cardiovascular markers in the prediction of adverse perinatal and maternal outcomes in women with suspected or confirmed pre-eclampsia.

METHODS

This was a prospective prognostic accuracy study of women with suspected or confirmed pre-eclampsia who underwent a series of investigations to measure maternal hemodynamic indices, mean arterial pressure, augmentation index, ophthalmic artery peak systolic velocity (PSV) ratio, uterine artery pulsatility index (UtA-PI), fetal biometric and Doppler parameters, soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF). The performance of these markers, individually or in combination, in predicting adverse perinatal and maternal outcomes was then assessed using receiver-operating-characteristics (ROC)-curve analysis. Adverse maternal outcome was defined as one or more of severe hypertension, admission to the intensive care unit, eclampsia, placental abruption, HELLP syndrome, disseminated intravascular coagulation, platelets < 100 × 109 /L, creatinine > 90 μmol/L and alanine aminotransferase > 100 U/L. Adverse perinatal outcome was defined as one or more of preterm birth at or before 34 + 0 weeks, neonatal intensive care unit admission for > 48 h, respiratory distress syndrome, intraventricular hemorrhage, hypoxic ischemic encephalopathy, necrotizing enterocolitis, retinopathy of prematurity and confirmed fetal infection.

RESULTS

We recruited 126 women with suspected (n = 31) or confirmed (n = 95) pre-eclampsia at a median gestational age of 33.9 weeks (interquartile range, 30.9-36.3 weeks). Pregnancies with adverse perinatal outcome compared to those without had a higher median UtA-PI (1.3 vs 0.8; P < 0.001), ophthalmic artery PSV ratio (0.8 vs 0.7; P = 0.01) and umbilical artery PI percentile (82.0 vs 68.5; P < 0.01) and lower median estimated fetal weight percentile (4.0 vs 43.0; P < 0.001), abdominal circumference percentile (4.0 vs 63.0; P < 0.001), middle cerebral artery PI percentile (28.0 vs 58.5; P < 0.001) and cerebroplacental ratio percentile (18.0 vs 46.5; P < 0.001). Pregnancies with adverse perinatal outcome also had a higher median sFlt-1 (8208.0 pg/mL vs 4508.0 pg/mL; P < 0.001), lower PlGF (27.2 pg/mL vs 76.3 pg/mL; P < 0.001) and a higher sFlt-1/PlGF ratio (445.4 vs 74.4; P < 0.001). The best performing individual marker for predicting adverse perinatal outcome was the sFlt-1/PlGF ratio (area under the ROC curve (AUC), 0.87 (95% CI, 0.81-0.93)), followed by estimated fetal weight (AUC, 0.81 (95% CI, 0.73-0.89)). Women who experienced adverse maternal outcome had a higher median sFlt-1 level (7471.0 pg/mL vs 5131.0 pg/mL; P < 0.001) and sFlt-1/PlGF ratio (204.3 vs 93.3; P < 0.001) and a lower PlGF level (37.0 pg/mL vs 66.1 pg/mL; P = 0.01) and estimated fetal weight percentile (16.5 vs 37.0; P = 0.04). All markers performed poorly in predicting adverse maternal outcome, with sFlt-1 (AUC, 0.69 (95% CI, 0.60-0.79)) and sFlt-1/PlGF ratio (AUC, 0.69 (95% CI, 0.59-0.78)) demonstrating the best individual performance. The addition of cardiovascular, fetal or other placental indices to the sFlt-1/PlGF ratio did not improve the prediction of adverse maternal or perinatal outcomes.

CONCLUSIONS

The sFlt-1/PlGF ratio performs well in predicting adverse perinatal outcomes but is a poor predictor of adverse maternal outcomes in women with suspected or diagnosed pre-eclampsia. The addition of cardiovascular or fetal indices to the model is unlikely to improve the prognostic performance of the sFlt-1/PlGF ratio. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Doppler Ultrasound of the Umbilical Artery: Clinical Application

OBJECTIVE

 To provide a survey of relevant literature on umbilical artery Doppler ultrasound use in clinical practice, technical considerations and limitations, and future perspectives.

METHODS

 Literature searches were conducted in PubMed and Medline, restricted to articles written in English. Additionally, the references of all analyzed studies were searched to obtain necessary information.

RESULTS

 The use of this technique as a routine surveillance method is only recommended for high-risk pregnancies with impaired placentation. Meta-analyses of randomized trials have established that obstetric management guided by umbilical artery Doppler findings can improve perinatal mortality and morbidity. The values of the indices of Umbilical artery Doppler decrease with advancing gestational age; however, a lack of consensus on reference ranges prevails.

CONCLUSION

 Important clinical decisions are based on the information obtained with umbilical artery Doppler ultrasound. Future efforts in research are imperative to overcome the current limitations of the technique.

Cerebroplacental ratio and neonatal outcome in low-risk pregnancies with reduced fetal movement: A prospective study

Objective

To evaluate the effectiveness of the cerebroplacental ratio (CPR) in predicting poor outcomes in low-risk pregnancies with reduced fetal movements (RFMs).

Study Design

This prospective study included singleton pregnancies at 28–40 weeks, presenting with RFM but no additional risk factors. Sub analysis was performed for pregnancies between 36 and 40 weeks. Umbilical artery (UA) and middle cerebral artery (MCA) pulsatility indices (PIs) were measured, and the MCA-PI to UA-PI ratio (CPR) was calculated. Mode of delivery, gestational age, fetal monitoring category, Apgar score at 1 and 5 min, birth weight, presence of meconium, umbilical artery pH, and neonatal intensive care unit (NICU) admission were recorded. Women with good and poor outcomes were compared with doppler indices and pregnancy characteristics.

Results

Of 96 women, 86 had good outcomes. There was no significant difference in UA-PI (0.871 ± 0.171 vs. 0.815 ± 0.179, P = 0.446), MCA-PI (1.778 ± 0.343 vs. 1.685 ± 0.373, P = 0.309), or CPR (2.107 ± 0.635 vs. 2.09 ± 0.597, P = 0.993) between the poor and good outcome groups. No difference was found in the location of the placenta, biophysical profile (BPP) score, fetal sex, or amniotic fluid index (AFI) at the time of presentation. The proportion of nulliparous patients in the poor outcome group was higher than that of multiparous patients. Sub analysis for 36–40 weeks revealed the same results; no significant difference in UA-PI (0.840 ± 0.184 Vs 0.815 ± 0.195, P = 0.599), MCA-PI (1.724 ± 0.403 vs. 1.626 ± 0.382, P = 0.523), or CPR (2.14 ± 0.762 vs. 2.08 ± 0.655, P = 0.931) between poor and good outcome groups.

Conclusions

CPR is not predictive of neonatal outcome in low-risk pregnancies with RFM. However, a higher proportion of poor outcomes in nulliparous women warrants further investigation.

Ophthalmic artery Doppler at 35-37 weeks' gestation in pregnancies with small or growth-restricted fetuses

OBJECTIVES

First, to compare the ophthalmic artery peak systolic velocity (PSV) ratio at 35-37 weeks' gestation among women who delivered small-for-gestational-age (SGA) or growth-restricted (FGR) neonates in the absence of hypertensive disorders, women who developed pre-eclampsia (PE) or gestational hypertension (GH) and those without SGA, FGR, PE or GH. Second, to examine the association of PSV ratio with placental growth factor (PlGF) and mean arterial pressure (MAP). Third, to assess the associations of PSV ratio, PlGF and MAP with birth-weight Z-score and percentile.

METHODS

This was a prospective observational study in women attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination of fetal anatomy and growth, and measurement of maternal ophthalmic artery PSV ratio, first (PSV1) and second (PSV2) peaks of systolic velocity, MAP and serum PlGF. The values of PSV ratio, MAP and PlGF were converted to multiples of the median (MoM) or delta values, and the median MoM or delta of these variables in the SGA, FGR, PE and GH groups were compared with those in the unaffected group. Regression analysis was used to examine the relationship of PSV ratio delta, PlGF MoM and MAP MoM with birth-weight Z-score after exclusion of PE and GH cases. Regression analysis was also used to examine the association of PSV ratio delta with log₁₀ PlGF MoM and log₁₀ MAP MoM.

RESULTS

The study population included 2287 pregnancies, of which 1954 (85.4%) were not affected by FGR, SGA, PE or GH, 49 (2.1%) were complicated by FGR in the absence of PE or GH, 160 (7.0%) had SGA in the absence of FGR, PE or GH, 60 (2.6%) had PE and 64 (2.8%) had GH. Compared with unaffected pregnancies, in both the FGR and SGA groups, the means of PSV ratio delta (0.042 (95% CI, 0.007-0.076) and 0.032 (95% CI, 0.016-0.049), respectively) and MAP MoM (1.028 (95% CI, 1.006-1.050) and 1.048 (95% CI, 1.035-1.060), respectively) were increased, while the mean of PlGF MoM was decreased (0.495 (95% CI, 0.393-0.622) and 0.648 (95% CI, 0.562-0.747), respectively). However, the magnitude of these changes was smaller than in the PE and GH groups. Ophthalmic artery waveform analysis revealed that the predominant feature of pregnancies complicated by SGA in the absence of hypertensive disorders was a reduction in PSV1, whereas, in those with hypertensive disorders, there was an increase in PSV2. In non-hypertensive pregnancies, there were linear inverse associations of PSV ratio delta and MAP MoM with birth-weight Z-score, with increased values in small neonates and decreased values in large neonates. There was a quadratic relationship between PlGF MoM and birth-weight Z-score, with low PlGF levels in small neonates and high PlGF levels in large neonates. There was a significant correlation of ophthalmic artery PSV ratio delta with both log₁₀ MAP MoM (0.124 (95% CI, 0.069-0.178)) and log₁₀ PlGF MoM (-0.238 (95% CI, -0.289 to -0.185)).

CONCLUSION

Assuming that the ophthalmic artery PSV ratio is a reflection of the interplay between cardiac output and peripheral vascular resistance, the linear association between PSV ratio and birth-weight Z-score in non-hypertensive pregnancies suggests the presence of a continuous physiological relationship between fetal size and cardiovascular response rather than a dichotomous relationship between high peripheral resistance and low cardiac output in small compared with non-small fetuses. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

The heart after surviving twin-to-twin transfusion syndrome

BACKGROUND

The persistent changes in cardiac structure and function in children who survived twin-to-twin transfusion syndrome remain a matter of concern and controversy. Current fetal echocardiographic parameters and their postnatal evolution can help improve our understanding of the subject.

OBJECTIVE

To describe the echocardiographic changes of monochorionic fetuses affected by twin-to-twin transfusion syndrome, the recipient and the donor, before and after laser photocoagulation and to determine their evolution in the third trimester and during their first year of life.

STUDY DESIGN

An observational study was conducted including 55 uncomplicated monochorionic diamniotic twins and 78 pairs with twin-to-twin transfusion syndrome, 44 stage I-II and 34 stage III-IV, prospectively enrolled from 2015 until 2018. Comprehensive echocardiography was performed at 4 time periods: before laser photocoagulation, at 24 to 72 hours after surgery, at 28 to 30 weeks of gestation, and at 6 to 12 months after birth. Echocardiographic parameters were transformed to z-scores or indexed for heart area, estimated fetal weight, or body mass surface.

RESULTS

At diagnosis, recipients in all stages presented larger hearts (cardiothoracic ratio z-score: 2.77 [0.8] vs controls: -0.03 [0.5]; P<.001) and signs of ventricular hypertrophy (left end-diastolic ventricle wall thickness: 2.68 [0.7] vs controls -0.03 [0.7]; P<.001), along with systolic (cardiac index recipients: 317 [114] mL/min/kg vs controls: 400 [120] mL/min/kg, P<.001) and diastolic impairment (isovolumetric relaxation time z-score: 2.76 [0.6] vs controls: 0.05 [0.6]; P<.001). Donors presented smaller ventricular areas and diameters when compared with controls (left end-diastolic ventricle area z-score: -1.48 [1] vs 0.03 [0.9]; P<.001), along with decreased longitudinal motion (tricuspid annular plane systolic excursion z-score: -0.9 [1] vs controls -0.04 [1]; P<.001) and shorter ejection time z-score (-1.5 [0.7] vs controls: 0.0 [0.7]; P<.001). After surgery, an improvement in functional parameters was observed in both fetuses, whereas most morphometric changes prevailed in donors and recipients in the prenatal period. Postnatally, cardiac remodeling persisted in recipients (left relative wall thickness: 0.34 [0.02] vs controls: 0.30 [0.02]; P<.001), whereas donors mainly presented a decreased longitudinal motion in infancy (tricuspid annular plane systolic excursion z-score: -0.72 [0.7] vs controls: 0.23 [0.9]; P<.05).

CONCLUSION

Cardiac remodeling is present in both fetuses at the twin-to-twin transfusion syndrome diagnosis, whereas diastolic dysfunction is only significant in the recipient. Fetal therapy improves most echocardiographic parameters, although postnatally, the echocardiographic changes persist in both fetuses.

Management of fetal Growth Restriction at term by Angiogenic Factors versus feto-maternal Doppler (GRAFD) to avoid adverse perinatal outcomes: multicenter open-label randomized controlled trial study protocol (Preprint)

Background

Fetal smallness affects 10% of pregnancies. Small fetuses are at a higher risk of adverse outcomes. Their management using estimated fetal weight and feto-maternal Doppler has a high sensitivity for adverse outcomes; however, more than 60% of fetuses are electively delivered at 37 to 38 weeks. On the other hand, classification using angiogenic factors seems to have a lower false-positive rate. Here, we present a protocol for the Fetal Growth Restriction at Term Managed by Angiogenic Factors Versus Feto-Maternal Doppler (GRAFD) trial, which compares the use of angiogenic factors and Doppler to manage small fetuses at term.

Objective

The primary objective is to demonstrate that classification based on angiogenic factors is not inferior to estimated fetal weight and Doppler at detecting fetuses at risk of adverse perinatal outcomes.

Methods

This is a multicenter, open-label, randomized controlled trial conducted in 20 hospitals across Spain. A total of 1030 singleton pregnancies with an estimated fetal weight ≤10th percentile at 36+0 to 37+6 weeks+days will be recruited and randomly allocated to either the control or the intervention group. In the control group, standard Doppler-based management will be used. In the intervention group, cases with a soluble fms-like tyrosine kinase to placental growth factor ratio ≥38 will be classified as having fetal growth restriction; otherwise, they will be classified as being small for gestational age. In both arms, the fetal growth restriction group will be delivered at ≥37 weeks and the small for gestational age group at ≥40 weeks. We will assess differences between the groups by calculating the relative risk, the absolute difference between incidences, and their 95% CIs.

Results

Recruitment for this study started on September 28, 2020. The study results are expected to be published in peer-reviewed journals and disseminated at international conferences in early 2023.

Conclusions

The angiogenic factor–based protocol may reduce the number of pregnancies classified as having fetal growth restriction without worsening perinatal outcomes. Moreover, reducing the number of unnecessary labor inductions would reduce costs and the risks derived from possible iatrogenic complications. Additionally, fewer inductions would lower the rate of early-term neonates, thus improving neonatal outcomes and potentially reducing long-term infant morbidities.

Trial Registration

ClinicalTrials.gov NCT04502823; https://clinicaltrials.gov/ct2/show/NCT04502823

International Registered Report Identifier (IRRID)

DERR1-10.2196/37452

The utility of foetal splenic artery Doppler measurement in the diagnosis of late-onset foetal growth restriction

We aimed to examine the contribution of splenic artery (SA) Doppler parameters in the detection of foetuses with late-onset foetal growth restriction (LO-FGR) and to evaluate its power in predicting adverse perinatal outcomes. Within the study's scope, 52 cases in the LO-FGR group and 92 cases in the control group were evaluated. The criteria determined in the Delphi procedure by an international consensus were used to define the LO-FGR. Middle cerebral artery (MCA) pulsatility index (PI) and SA PI were significantly lower in the LO-FGR group (p: .002, p<.001, respectively). Likewise, cerebroplacental ratio (CPR) was significantly lower in the LO-FGR group (p<.001). Decreased CPR and decreased SA PI were significantly and positively associated with an increased likelihood of exhibiting adverse obstetric outcome (p<.001, p: .012, respectively). The receiver operating characteristic (ROC) curve analysis showed that the optimal cut-off value for SA PI was 1.41 to predict LO-FGR with 70.7% sensitivity and 61.5% specificity (AUC = 0.684; 95% CI, 0.594-0.774).Impact StatementWhat is already known on this subject? The main clinical difficulty in late-onset foetal growth restriction (LO-FGR) is the detection of the disease.What do the results of this study add? The splenic artery (SA) pulsatility index (PI) may contribute to both diagnostic and the prediction of adverse perinatal outcomes in LO-FGR cases. Our results showed that the SA PI value, as well as cerebroplacental ratio (CPR), can be a useful parameter in predicting negative outcomes.What are the implications of these findings for clinical practice and/or further research? Various degrees of uteroplacental insufficiency in foetuses with LO-FGR may be associated with abnormalities in SA Doppler velocimetry. Splenic artery Doppler velocimetry can be used for the clinical management of LO-FGR.

Syncytiotrophoblast stress in preeclampsia: the convergence point for multiple pathways

Preeclampsia evolves in 2 stages: a placental problem that generates signals to the mother to cause a range of responses that comprise the second stage (preeclampsia syndrome). The first stage of early-onset preeclampsia is poor placentation, which we here call malplacentation. The spiral arteries are incompletely remodeled, leading to later placental malperfusion, relatively early in the second half of pregnancy. The long duration of the first stage (several months) is unsurprisingly associated with fetal growth restriction. The first stage of late-onset preeclampsia, approximately 80% of total cases, is shorter (several weeks) and part of a process that is common to all pregnancies. Placental function declines as it outgrows uterine capacity, with increasing chorionic villous packing, compression of the intervillous space, and fetal hypoxia, and causes late-onset clinical presentations such as "unexplained" stillbirths, late-onset fetal growth restriction, or preeclampsia. The second stages of early- and late-onset preeclampsia share syncytiotrophoblast stress as the most relevant feature that causes the maternal syndrome. Syncytiotrophoblast stress signals in the maternal circulation are probably the most specific biomarkers for preeclampsia. In addition, soluble fms-like tyrosine kinase-1 (mainly produced by syncytiotrophoblast) is the best-known biomarker and is routinely used in clinical practice in many locations. How the stress signals change over time in normal pregnancies indicates that syncytiotrophoblast stress begins on average at 30 to 32 weeks' gestation and progresses to term. At term, syncytiotrophoblast shows increasing markers of stress, including apoptosis, pyroptosis, autophagy, syncytial knots, and necrosis. We label this phenotype the "twilight placenta" and argue that it accounts for the clinical problems of postmature pregnancies. Senescence as a stress response differs in multinuclear syncytiotrophoblast from that of mononuclear cells. Syncytiotrophoblast irreversibly acquires part of the senescence phenotype (cell cycle arrest) when it is formed by cell fusion. The 2 pathways converge on the common pathologic endpoint, syncytiotrophoblast stress, and contribute to preeclampsia subtypes. We highlight that the well-known heterogeneity of the preeclampsia syndrome arises from different pathways to this common endpoint, influenced by maternal genetics, epigenetics, lifestyle, and environmental factors with different fetal and maternal responses to the ensuing insults. This complexity mandates a reassessment of our approach to predicting and preventing preeclampsia, and we summarize research priorities to maximize what we can learn about these important issues.

A machine-learning-based algorithm improves prediction of preeclampsia-associated adverse outcomes

BACKGROUND

Preeclampsia presents a highly prevalent burden on pregnant women with an estimated incidence of 2% to 5%. Preeclampsia increases the maternal risk of death 20-fold and is one of the main causes of perinatal morbidity and mortality. Novel biomarkers, such as soluble fms-like tyrosine kinase-1 and placental growth factor in addition to a wide span of conventional clinical data (medical history, physical symptoms, laboratory parameters, etc.), present an excellent basis for the application of early-detection machine-learning models.

OBJECTIVE

This study aimed to develop, train, and test an automated machine-learning model for the prediction of adverse outcomes in patients with suspected preeclampsia.

STUDY DESIGN

Our real-world dataset of 1647 (2472 samples) women was retrospectively recruited from women who presented to the Department of Obstetrics at the Charité - Universitätsmedizin Berlin, Berlin, Germany, between July 2010 and March 2019. After standardization and data cleaning, we calculated additional features regarding the biomarkers soluble fms-like tyrosine kinase-1 and placental growth factor and sonography data (umbilical artery pulsatility index, middle cerebral artery pulsatility index, mean uterine artery pulsatility index), resulting in a total of 114 features. The target metric was the occurrence of adverse outcomes throughout the remaining pregnancy and 2 weeks after delivery. We trained 2 different models, a gradient-boosted tree and a random forest classifier. Hyperparameter training was performed using a grid search approach. All results were evaluated via a 10 × 10-fold cross-validation regimen.

RESULTS

We obtained metrics for the 2 naive machine-learning models. A gradient-boosted tree model was performed with a positive predictive value of 88%±6%, a negative predictive value of 89%±3%, a sensitivity of 66%±5%, a specificity of 97%±2%, an overall accuracy of 89%±3%, an area under the receiver operating characteristic curve of 0.82±0.03, an F1 score of 0.76±0.04, and a threat score of 0.61±0.05. The random forest classifier returned an equal positive predictive value (88%±6%) and specificity (97%±1%) while performing slightly inferior on the other available metrics. Applying differential cutoffs instead of a naive cutoff for positive prediction at ≥0.5 for the classifier's results yielded additional increases in performance.

CONCLUSION

Machine-learning techniques were a valid approach to improve the prediction of adverse outcomes in pregnant women at high risk of preeclampsia vs current clinical standard techniques. Furthermore, we presented an automated system that did not rely on manual tuning or adjustments.

Brain-Derived Neurotrophic Factor Levels in Cord Blood from Growth Restricted Fetuses with Doppler Alteration Compared to Adequate for Gestational Age Fetuses

Background and Objectives: Fetal growth restriction (FGR) is a severe obstetric disease characterized by a low fetal size entailing a set of undesired consequences. For instance, previous studies have noticed a worrisome association between FGR with an abnormal neurodevelopment. However, the precise link between FGR and neurodevelopmental alterations are not yet fully understood yet. Brain-derived neurotrophic factor (BDNF) is a critical neurotrophin strongly implicated in neurodevelopmental and other neurological processes. In addition, serum levels of BDNF appears to be an interesting indicator of pathological pregnancies, being correlated with the neonatal brain levels. Therefore, the aim of this study is to analyze the blood levels of BDNF in the cord blood from fetuses with FGR in comparison to those with weight appropriate for gestational age (AGA). Materials and Methods: In this study, 130 subjects were recruited: 91 in group A (AGA fetuses); 39 in group B (16 FGR fetuses with exclusively middle cerebral artery (MCA) pulsatility index (PI) < 5th percentile and 23 with umbilical artery (UA) PI > 95th percentile). Serum levels of BDNF were determined through ELISA reactions in these groups. Results: Our results show a significant decrease in cord blood levels of BDNF in FGR and more prominently in those with UA PI >95th percentile in comparison to AGA. FGR fetuses with exclusively decreased MCA PI below the 5th percentile also show reduced levels of BDNF than AGA, although this difference was not statistically significant. Conclusions: Overall, our study reports a potential pathophysiological link between reduced levels of BDNF and neurodevelopmental alterations in fetuses with FGR. However, further studies should be conducted in those FGR subjects with MCA PI < 5th percentile in order to understand the possible implications of BDNF in this group.

Comparison of fetal lung maturation in fetuses with intrauterine growth restriction with control group, using lung volume, lung/liver and lung/muscle signal intensity and apparent diffusion coefficient ratios on different magnetic resonance imaging sequences

PURPOSE

To compare lung volume, lung apparent diffusion coefficient (ADC) and signal intensity ratio (SIR) on different magnetic resonance imaging (MRI) sequences between intrauterine growth restriction (IUGR) fetuses and the control group.

MATERIALS AND METHODS

49 IUGR and 58 non-IUGR fetuses were imaged using 3 Tesla MRI units. Total lung volume (TLV), lung/liver SIR (LLSIR) and lung/muscle SIR (LMSIR) in T1 and T2-weighted sequences and lung/liver ADC ratio (LLADCR) and lung/muscle ADC ratio (LMADCR) were assessed.

RESULTS

LLSIR and LMSIR were significantly higher in the T1-weighted sequence (p-value: .03) and LLADCR and LMADCR were significantly lower on diffusion-weighted imaging (DWI) in IUGR fetuses compared to the control group (p-value: .01). There was no significant difference in SIRs in the T2-weighted sequence between the two groups. Although TLV was increased with gestational age in both groups, it was significantly lower in the IUGR group (mean: 82 ± 22.7 ml vs. 110.8 ± 18 ml, p-value: <.001).

CONCLUSION

The T1-weighted sequence and DWI seem to be better than the T2-weighted sequence for assessing the faint difference of lung maturity between groups. However, SIR differences were not as meaningful as TLV differences and this could be related to the complex maturation process in IUGR fetuses as the effect of higher endogenous corticosteroids.

Reference values for fetal Doppler-based cardiocirculatory indices in monochorionic-diamniotic twin pregnancy

Background

Placental anastomoses in monochorionic diamniotic (MCDA) twin pregnancy have a major impact on fetal circulation. This study was designed to define reference ranges of cardiac and vascular Doppler indices in MCDA twin pregnancies.

Methods

This cross-sectional study included 442 uncomplicated MCDA twin fetuses undergoing Doppler ultrasonography at 18–35 weeks of gestation. Left and right myocardial performance index (LV-MPI, RV-MPI), E/A ratio of atrioventricular valves, pulsatility indices of umbilical artery, middle cerebral artery (MCA), and ductus venosus (DV), cerebroplacental ratio, peak systolic velocity of MCA, S/a ratio of DV, and early diastolic filling time of ductus venosus (DV-E) were evaluated under standardized settings. The equation models between Doppler indices and gestational age (GA) were fitted. After adjustment for GA, the correlations between MPI and fetal heart rate (FHR), and between MPI and DV indices were analyzed.

Results

Estimated centiles of Doppler indices were derived as a function of GA, being distinct in values from those of singletons. There was no correlation between GA-adjusted MPI and FHR. DV-E was inversely related to LV-MPI.

Conclusions

MCDA twins showed significant changes in some Doppler indices throughout gestation with quantitative differences from singletons, emphasizing the importance of MC twin-specific reference values for clinical application. Further adjustment of MPI for FHR was unnecessary. DV-E is a vascular index indirectly representing fetal diastolic function.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04255-w.

Analysis of Proteomic Characteristics of Peripheral Blood in Preeclampsia and Study of Changes in Fetal Arterial Doppler Parameters Based on Magnetic Nanoparticles

Background

Traditional mass spectrometry detection methods have low detection efficiency for low-abundance proteins, thus limiting the application of proteomic analysis in the diagnosis of preeclampsia. Magnetic nanomaterials have good superparamagnetism and have obvious advantages in the field of biological separation and enrichment.

Aim

The objective of this study is to explore the value of superparamagnetic iron oxide nanoparticles in the proteomic analysis of preeclampsia.

Materials and Methods

42 patients and 40 normal pregnant women were selected in this study for analysis. Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed to evaluate the function of these differential proteins. Proteomic analysis was used to analyze the differential proteins. Color Doppler ultrasound technology was used to detect changes in the blood flow of the fetal umbilical artery and cerebral artery.

Results

16 differential proteins in the serum of pregnant women with preeclampsia and normal pregnant women were detected. The 16 proteins are mainly related to angiogenesis and endothelial function proteins, coagulation cascade proteins, placental growth factor, and so on. Biological function analysis revealed that these proteins are mainly enriched in the nuclear factor kB (NF-κB) signaling pathway. Moreover, our data suggested that compared with the fetus in the uterus of normal pregnant women, the umbilical artery S/D, PI, and RI of the fetus in preeclampsia were greatly increased, and the cerebral artery S/D, PI, and RI were greatly decreased.

Conclusion

Biological function analysis revealed that 16 proteins are mainly enriched in the NF-κB signaling pathway. Compared with the normal group, the umbilical artery S/D, PI, and RI of the preeclampsia group were greatly increased, and the cerebral artery S/D, PI, and RI were all greatly reduced. Our findings provided a more comprehensive reference for us to study the mechanism of preeclampsia at the molecular level and also provide data support for the screening of relevant markers for early diagnosis of preeclampsia.

Uterine Artery Doppler Reference Ranges in a Twin Caucasian Population Followed Longitudinally From 17 to 37 Weeks Gestation Compared to That of Singletons

OBJECTIVES

The primary aim was to measure uterine artery (UtA) indices in twin pregnancies of Polish Caucasian women and compare it with a previously published study by Geipel et al for DC twins (2011). The secondary aim was to find differences in UtA indices in MC, DC twins, and singletons.

METHODS

A prospective longitudinal evaluation of UtA Doppler indices in 1462 examinations of twins and 5766 examinations of singletons between 17 and 37 gestational age (GA). Pulsatility index (PI) and resistance index (RI) were calculated.

RESULTS

UtA PI and RI are lower in the twins than singletons but the analyzed mean values throughout gestation are higher than the study presented by Geipel et al. Obtained curves for DC twins and singletons had the same form as Geipel's curves. In MC twins, curves are flatter and characterized by lower differences throughout pregnancy than Geipel's curves for DC twins. They tend to be more similar about 32 weeks of gestations, resulting from different placenta structure in MC than DC twin pregnancies.

CONCLUSIONS

UtA Doppler indices in twin pregnancies are lower than in singletons. Obtained data have higher values for twins than reference charts proposed by Geipel's for dichorionic twins. We observed some differences between monochorionic and dichorionic twins' curves throughout pregnancy, but they were not significant.

Fetal cerebral blood-flow redistribution: analysis of Doppler reference charts and association of different thresholds with adverse perinatal outcome

OBJECTIVES

First, to compare published Doppler reference charts of the ratios of flow in the fetal middle cerebral and umbilical arteries (i.e. the cerebroplacental ratio (CPR) and umbilicocerebral ratio (UCR)). Second, to assess the association of thresholds of CPR and UCR based on these charts with short-term composite adverse perinatal outcome in a cohort of pregnancies considered to be at risk of late preterm fetal growth restriction.

METHODS

Studies presenting reference charts for CPR or UCR were searched for in PubMed. Formulae for plotting the median and the 10^th percentile (for CPR) or the 90^th percentile (for UCR) against gestational age were extracted from the publication or calculated from the published tables. Data from a prospective European multicenter observational cohort study of singleton pregnancies at risk of fetal growth restriction at 32 + 0 to 36 + 6 weeks' gestation, in which fetal arterial Doppler measurements were collected longitudinally, were used to compare the different charts. Specifically, the association of UCR and CPR thresholds (CPR < 10^th percentile or UCR ≥ 90^th percentile and multiples of the median (MoM) values) with composite adverse perinatal outcome was analyzed. The association was also compared between chart-based thresholds and absolute thresholds. Composite adverse perinatal outcome comprised both abnormal condition at birth and major neonatal morbidity.

RESULTS

Ten studies presenting reference charts for CPR or UCR were retrieved. There were large differences between the charts in the 10^th and 90^th percentile values of CPR and UCR, respectively, while median values were more similar. In the gestational-age range of 28-36 weeks, there was no relationship between UCR or CPR and gestational age. From the prospective observational study, 856 pregnancies at risk of late-onset preterm fetal growth restriction were included in the analysis. The association of abnormal UCR or CPR with composite adverse perinatal outcome was similar for percentile thresholds or MoM values, as calculated from the charts, and for absolute thresholds, both on univariable analysis and after adjustment for gestational age at measurement, estimated fetal weight MoM and pre-eclampsia. The adjusted odds ratio for composite adverse perinatal outcome was 3.3 (95% CI, 1.7-6.4) for an absolute UCR threshold of ≥ 0.9 or an absolute CPR threshold of < 1.11 (corresponding to ≥ 1.75 MoM), and 1.6 (95% CI, 0.9-2.9) for an absolute UCR threshold of ≥ 0.7 to < 0.9 or an absolute CPR threshold of ≥ 1.11 to < 1.43 (corresponding to ≥ 1.25 to < 1.75 MoM).

CONCLUSIONS

In the gestational-age range of 32 to 36 weeks, adjustment of CPR or UCR for gestational age is not necessary when assessing the risk of adverse outcome in pregnancies at risk of fetal growth restriction. The adoption of absolute CPR or UCR thresholds, independent of reference charts, is feasible and makes clinical assessment simpler than if using percentiles or other gestational-age normalized units. The high variability in percentile threshold values among the commonly used UCR and CPR reference charts hinders reliable diagnosis and clinical management of late preterm fetal growth restriction. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Serum Activin A as Brain Injury Biomarker in the First Three Days of Life. A Prospective Case-Control Longitudinal Study in Human Premature Neonates

Disruption of normal intrauterine brain development is a significant consequence of premature birth and may lead to serious complications, such as neonatal brain injury (NBI). This prospective case-control longitudinal study aimed at determining the levels and prognostic value of serum activin A during the first three days of life in human premature neonates which later developed NBI. It was conducted in a single tertiary hospital and eligible participants were live-born premature (<34 weeks) neonates. Each case (n = 29) developed NBI in the form of an intraventricular haemorrhage, or periventricular leukomalacia, and was matched according to birth weight and gestational age to one neonate with normal head ultrasound scans. Serum activin A levels in both groups showed a stable concentration during the first three days of life as no difference was observed within the two groups from the first to the third day. Neonates diagnosed with NBI had significantly higher activin A levels during the first two days of life compared to control neonates and its levels correlated to the severity of NBI during the second and third day of life. Although serum activin A on the second day was the best predictor for neonates at risk to develop NBI, the overall predictive value was marginally fair (area under the ROC-curve 69.2%). Activin A, in combination with other biomarkers, may provide the first clinically useful panel for the early detection of premature neonates at high risk of NBI.

Effect of Maternal and Fetal Characteristics in Feto-Placental Doppler and Impact of Using Adjusted Standards in the Definition of Fetal Growth Restriction at Term

INTRODUCTION

This study aimed to determine the effect and clinical impact of physiological characteristics on the 95th/5th centile of the umbilical artery (UA) Doppler and the cerebroplacental ratio (CPR), at 36+ weeks.

METHODS

From the multicenter randomized trial "Ratio37," we selected 4,505 low-risk pregnant women between June 2016 and January 2020. We registered physiological characteristics and the pulsatility indexes (PI) of the UA and middle cerebral artery (36-39 weeks). The 95th/5th centile of the UA PI and CPR was modeled by quantile regression. To evaluate the clinical impact of adjusting Doppler, we retrospectively applied gestational age (GA) and fully adjusted standards to 682 small for gestational age (SGA)-suspected fetuses (37 weeks) from a cohort of consecutive patients obtained between January 2010 and January 2020.

RESULTS

Several physiological characteristics significantly influenced the 95th/5th centile of the UA and CPR PI. The fully adjusted 95th centile of the UA was higher, and the 5th centile of the CPR was lower than GA-only-adjusted standards. Of the 682 SGA fetuses, 150 (22%) were classified as late fetal growth restricted only by GA and 112 (16.4%) when we adjusted Doppler. These 38 fetuses had similar perinatal outcome than the SGA group.

DISCUSSION

The 95th/5th centile of the UA and CPR PI is significantly influenced by physiological characteristics. Adjusting Doppler standards could differentiate better between FGR and SGA.

Prognostic Value of Angiogenic Markers in Pregnant Women With Chronic Hypertension

Background

Women with chronic hypertension face a 5‐ to 6‐fold increased risk of developing preeclampsia compared with normotensive women. Angiogenic markers, especially soluble fms‐like kinase 1 (sFlt‐1) and placental growth factor (PlGF), were identified as clinically useful markers predicting the development of preeclampsia, but data on the prediction of superimposed preeclampsia are scarce. Therefore, we aimed to evaluate the predictive value of the sFlt‐1/PlGF ratio for delivery because of superimposed preeclampsia in women with chronic hypertension.

Methods and Results

This retrospective study included 142 women with chronic hypertension and suspected superimposed preeclampsia. Twenty‐seven women (19.0%) delivered because of maternal indications only, 17 women (12.0%) because of fetal indications primarily, and 98 women (69.0%) for other reasons. Women who both delivered because of maternal indications and for fetal indications had a significantly higher sFlt‐1/PlGF ratio (median 99.9 and 120.2 versus 7.3, respectively, P<0.001 for both) and lower PlGF levels (median 73.6 and 53.3 versus 320.0 pg/mL, respectively, P<0.001 for both) compared with women who delivered for other reasons. SFlt‐1/PlGF ratio and PlGF were strong predictors for delivery because of superimposed preeclampsia, whether for maternal or fetal indications (P<0.05). Half of women with angiogenic imbalance (sFlt‐1/PlGF ratio ≥85 or PlGF levels <100 pg/mL) delivered because of maternal or fetal indications within 1.6 weeks (95% CI, 1.0–2.4 weeks).

Conclusions

Angiogenic marker imbalance in women with suspected superimposed preeclampsia can predict delivery because of maternal and fetal indications related to superimposed preeclampsia and is associated with a significantly shorter time to delivery interval.

Stillbirth Following Normal Ultrasound Findings and Maternal Placental Growth Factor Levels

BACKGROUND

Attempts to reduce the current rate of antepartum stillbirth in the late third trimester have largely focused on the accurate identification of fetal growth restriction. Universal ultrasound significantly increases detection, especially when combined with maternal angiogenic growth factors, but this screening strategy is not well suited to identify umbilical cord pathology. While this poses unique challenges to pregnancy care, the recurrence risk of cord obstruction is low in comparison with many intrinsic placental diseases.

CASE

A 30-year-old woman with normal uterine artery Doppler waveforms, fetal growth ultrasounds, and circulating placental growth factor experienced an unexpected third-trimester stillbirth. Placental pathology demonstrated fetal vascular malperfusion and cord hyper-coiling.

CONCLUSION

Despite normal placental function, the otherwise healthy fetus is at risk of antepartum stillbirth due to cord-related pathology.

Ultrasound and Doppler findings in pregnant women with SARS-CoV-2 infection

OBJECTIVES

To describe and compare ultrasound and Doppler findings in pregnant women who were positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with findings in those who were SARS-CoV-2-negative, evaluated during the pandemic period.

METHODS

In this retrospective case-control study, we analyzed data from 106 pregnant women who tested positive for SARS-CoV-2 at the time of, or within 1 week of, an ultrasound scan between 1 May and 31 August 2020. Scans were either performed for routine fetal evaluation or indicated due to a positive SARS-CoV-2 test. Forty-nine women were symptomatic and 57 were asymptomatic. For comparison, we analyzed data from 103 pregnant women matched for maternal age, parity, body mass index and gestational age at the time of the ultrasound scan. These control women did not report symptoms of SARS-CoV-2 infection at the time of the ultrasound scan or at the time of admission for delivery and had a negative SARS-CoV-2 test at admission for delivery. Fetal biometry, fetal anatomy, amniotic fluid volume and Doppler parameters, including umbilical and fetal middle cerebral artery pulsatility indices, cerebroplacental ratio and biophysical profile (BPP), were evaluated as indicated. Biometric and Doppler values were converted to Z-scores for comparison. Our primary outcome, an adverse prenatal composite outcome (APCO) included any one or more of: small-for-gestational-age (SGA) fetus, oligohydramnios, abnormal BPP, abnormal Doppler velocimetry and fetal death. Comorbidities, delivery information and neonatal outcome were compared between the two groups.

RESULTS

Eighty-seven (82.1%) women who were positive for SARS-CoV-2 had a body mass index > 25 kg/m2 . SARS-CoV-2-positive women had a higher prevalence of diabetes (26/106 (24.5%) vs 13/103 (12.6%); P = 0.03), but not of pre-eclampsia (21/106 (19.8%) vs 11/103 (10.7%); P = 0.08), compared with controls. The prevalence of APCO was not significantly different between SARS-CoV-2-positive women (19/106 (17.9%)) and controls (9/103 (8.7%)) (P = 0.06). There were no differences between SARS-CoV-2-positive women and controls in the prevalence of SGA fetuses (12/106 (11.3%) vs 6/103 (5.8%); P = 0.17), fetuses with abnormal Doppler evaluation (8/106 (7.5%) vs 2/103 (1.9%); P = 0.08) and fetuses with abnormal BPP (4/106 (3.8%) vs 0/103 (0%); P = 0.14). There were two fetal deaths in women who were positive for SARS-CoV-2 and these women had a higher rate of preterm delivery ≤ 35 weeks of gestation (22/106 (20.8%) vs 9/103 (8.7%); odds ratio, 2.73 (95% CI, 1.19-6.3); P = 0.01) compared with controls.

CONCLUSIONS

There were no significant differences in abnormal fetal ultrasound and Doppler findings observed between pregnant women who were positive for SARS-CoV-2 and controls. However, preterm delivery ≤ 35 weeks was more frequent among SARS-CoV-2-positive women. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Second trimester cerebroplacental ratio versus umbilicocerebral ratio for the prediction of adverse perinatal outcomes

INTRODUCTION

An abnormal third trimester cerebroplacental ratio has been previously associated with adverse perinatal outcome. The less studied inverse of the cerebroplacental ratio, the umbilicocerebral ratio, has been proposed as a better predictor of adverse perinatal outcome. However, little is known about the implication of either an abnormal cerebroplacental ratio or umbilicocerebral ratio in the second trimester. The objective of this study was to evaluate the relationship between an abnormal second trimester cerebroplacental ratio and adverse perinatal outcome and provide comparison to an abnormal second trimester umbilicocerebral ratio.

MATERIALS AND METHODS

This retrospective cohort study in a single tertiary referral center utilized data from all non-anomalous singleton pregnancies that underwent Doppler assessment of the cerebroplacental ratio between 20 and 28 weeks gestation. The study period was 1 January 2015 to 31 July 2018. Abnormal cerebroplacental ratio was defined as less than the 5th percentile for gestational age. If patients had more than one ultrasound during the study period (i.e. for serial assessment of fetal growth), the lowest value of the cerebroplacental ratio was recorded. The primary outcome was a composite of clinically relevant adverse perinatal outcomes including preterm delivery, small for gestational age, and neonatal intensive care unit admission. Secondary outcomes included urgent delivery for fetal distress (operative vaginal delivery or cesarean section) and hypertensive disorders of pregnancy. An abnormal umbilicocerebral ratio was defined as greater than 95th percentile for gestational age. Areas under the curve were calculated and compared for cerebroplacental ratio and umbilicocerebral ratio.

RESULTS

2326 pregnancies met inclusion criteria. Of these, 91 (3.9%) had an abnormal second trimester cerebroplacental ratio. Fetuses with an abnormal second trimester cerebroplacental ratio had a 2.3-fold (95% CI 1.5-3.6, p < .05) increased risk of adverse perinatal outcome after adjusting for potential confounders such as chronic hypertension, pregestational diabetes, and smoking during pregnancy. Significantly increased risks of preterm delivery (OR 2.0, 95% CI 1.1-38, p < .05) and neonatal intensive care unit admission (OR 2.1, 95% CI 1.2-3.6, p < .05) were also seen in a subgroup analysis of abnormal cerebroplacental ratio in appropriate for gestational age infants. 132 (5.7%) fetuses had an abnormal second trimester umbilicocerebral ratio, and these fetuses had a 2.0-fold (95% CI 1.4-3.0, p < .05) increased risk of adverse perinatal outcome. The area under the curve for CPR and UCR for prediction of the primary outcome was 0.6 for both (95% CI 0.57-0.61 and 0.57-0.62, respectively, both p < .05).

CONCLUSION

An abnormal second trimester cerebroplacental ratio or umbilicocerebral ratio is associated with adverse perinatal outcome. However, the predictive ability of either ratio remains suboptimal.

Influence of Cerebral Vasodilation on Blood Reelin Levels in Growth Restricted Fetuses

Fetal growth restriction (FGR) is one of the most important obstetric pathologies. It is frequently caused by placental insufficiency. Previous studies have shown a relationship between FGR and impaired new-born neurodevelopment, although the molecular mechanisms involved in this association have not yet been completely clarified. Reelin is an extracellular matrix glycoprotein involved in development of neocortex, hippocampus, cerebellum and spinal cord. Reelin has been demonstrated to play a key role in regulating perinatal neurodevelopment and to contribute to the emergence and development of various psychiatric pathologies, and its levels are highly influenced by pathological conditions of hypoxia. The purpose of this article is to study whether reelin levels in new-borns vary as a function of severity of fetal growth restriction by gestational age and sex. We sub-grouped fetuses in: normal weight group (Group 1, n = 17), FGR group with normal umbilical artery Doppler and cerebral redistribution at middle cerebral artery Doppler (Group 2, n = 9), and FGR with abnormal umbilical artery Doppler (Group 3, n = 8). Our results show a significant association of elevated Reelin levels in FGR fetuses with cerebral blood redistribution compared to the normal weight group and the FGR with abnormal umbilical artery group. Future research should focus on further expanding the knowledge of the relationship of reelin and its regulated products with neurodevelopment impairment in new-borns with FGR and should include larger and more homogeneous samples and the combined use of different in vivo techniques in neonates with impaired growth during their different adaptive phases.

Distinction between SGA and FGR by means of fetal umbilical vein flow and maternal hemodynamics

OBJECTIVES

To improve identification of fetal growth restriction (FGR) by means of umbilical venous flow (QUV) and maternal hemodynamics, including systemic vascular resistance (SVR) and cardiac output (CO), in order to distinguish between FGR and SGA.

METHODS

We enrolled 68 pregnancies (36 SGA, 8 early FGR and 24 late FGR) who underwent a complete fetal hemodynamic examination including QUV and a noninvasive maternal hemodynamics assessment by means of USCOM.

RESULTS

In comparison with SGA, QUV and corrected for estimated fetal weight QUV (cQUV) were significantly lower in early and late-FGR. In addition, maternal CO was lower in early and late-FGR, while SVR was lower only in early-onset FGR. According to ROC analysis, cQUV centile (AUC 0.92, 0.72) was the best parameter for the prediction of SGA before and after 32 weeks, followed by SVR and CO. For all parameters, the prediction was always better in the case of early-onset FGR <32 weeks.

CONCLUSIONS

UV flow and maternal hemodynamics examination are useful tools to accurately discern between SGA and FGR.

Perinatal Outcome of Selective Intrauterine Growth Restriction in Monochorionic Twins: Evaluation of a Retrospective Cohort in a Developing Country

Selective intrauterine growth restriction (sIUGR) in monochorionic twin pregnancies is associated with greater morbidity and mortality for both fetuses when compared to singleton and dichorionic pregnancies. This retrospective cohort study aimed to assess the perinatal outcomes of monochorionic twin pregnancies affected by this disorder and conducted expectantly, by analyzing the results according to the end-diastolic flow in the umbilical artery Doppler of the smaller twin (type I: persistently forward/type II: persistently absent or reversed/type III: intermittently absent or reversed). Seventy-five monochorionic diamniotic twin pregnancies with sIUGR were included in this study. sIUGR was defined by estimated fetal weight below the 3rd centile for gestational age, or below the 10th centile, when associated with at least one of the following three criteria: abdominal circumference below the 10th percentile, umbilical artery pulsatility index of the smaller twin above the 95th percentile, or estimated fetal weight discordance of 25% or more. Perinatal outcomes were analyzed from the prenatal period to hospital discharge and included perinatal death, neurological injury, retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), and sepsis. The mortality rate was 1.33% in this cohort. The overall morbidity rate was lower in type I twin pregnancies. In conclusion, this study shows that sIUGR type I has lower morbidity than types II and III in expectant management.

Fetal Umbilical Vein Flow in the Classification of Fetuses with Growth Restriction

Objectives: To assess umbilical vein (UV) blood flow in fetal growth restriction (FGR) and in pregnancy with small for gestational age (SGA) fetus. To evaluate the predictive capacity of UV blood flow (QUV) in the discrimination of SGA fetuses from FGR before and after 32 weeks of pregnancy. Methods: Sixty-five women with a recent diagnosis of FGR or SGA fetuses were enrolled and underwent a complete fetal Doppler examination comprehending QUV. We collected SGA (n = 34), early-FGR (n = 9), and late-FGR (n = 22) fetuses. Results: UV diameter was lower in early and late-FGR compared to SGA, while time-averaged maximum velocity (TAMXV) was lower only in early-FGR. UV blood flow (QUV) and QUV corrected for estimated fetal weight (cQUV) were significantly lower in early-FGR and late-FGR compared to SGA. The receiver operating characteristic (ROC) curves analysis of cQUV showed a significant predictive capacity for SGA diagnosis before and after 32 weeks. Conclusions: The evaluation of UV blood flow allows distinguishing SGA fetuses from FGR. The assessment of UV flow should be taken into consideration in future research of new parameters to differentiate SGA from FGR.

Fetal cardiac function at 35-37 weeks' gestation in pregnancies that subsequently develop pre-eclampsia

OBJECTIVE

To compare fetal cardiac morphology and function between pregnancies that subsequently developed pre-eclampsia (PE) and those that remained normotensive.

METHODS

This was a prospective observational study in 1574 pregnancies at 35-37 weeks' gestation, including 76 that subsequently developed PE. We carried out comprehensive assessment of fetal cardiac morphology and function including novel imaging modalities, such as speckle-tracking echocardiography, and measured uterine artery pulsatility index, mean arterial pressure (MAP), serum placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and cerebroplacental ratio (CPR). The findings in the group that subsequently developed PE were compared to those in pregnancies that remained normotensive.

RESULTS

In fetuses of mothers who subsequently developed PE, compared to those from normotensive pregnancies, there was a more globular right ventricle, as shown by reduced right ventricular sphericity index, reduced right ventricular systolic contractility, as shown by reduced global longitudinal strain, and reduced left ventricular diastolic function, as shown by increased E/A ratio. On multivariable regression analysis, these indices demonstrated an association with PE, independent of maternal characteristics and fetal size. In pregnancies that subsequently developed PE, compared to those that remained normotensive, MAP, sFlt-1 and the incidence of low birth weight were higher, whereas serum PlGF, CPR and the interval between assessment and delivery were lower. These findings demonstrate that, in pregnancies that develop PE, there is evidence of impaired placentation, reflected in low PlGF and reduced birth weight, placental ischemia, evidenced by increased sFlt-1 which becomes apparent in the interval of 2-4 weeks preceding the clinical onset of PE, and consequent fetal hypoxia-induced redistribution in the fetal circulation, reflected in the low CPR.

CONCLUSION

Although the etiology of the observed fetal cardiac changes in pregnancies that subsequently develop PE remains unclear, it is possible that the reduction in right-heart systolic function is the consequence of high afterload due to increased placental resistance, whilst the early left ventricular diastolic changes could be due to fetal hypoxia-induced redistribution in the fetal circulation. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

The ability of various cerebroplacental ratio thresholds to predict adverse neonatal outcomes in term fetuses exhibiting late-onset fetal growth restriction

OBJECTIVES

Our primary aim was to evaluate the ability of various cerebroplacental ratio (CPR) reference values suggested by the Fetal Medicine Foundation to predict adverse neonatal outcomes in term fetuses exhibiting late-onset fetal growth restriction (LOFGR). Our secondary aim was to evaluate the effectiveness of other obstetric Doppler parameters used to assess fetal well-being in terms of predicting adverse neonatal outcomes.

METHODS

This was a retrospective cohort study of 317 pregnant women diagnosed with LOFGR at 37-40 weeks of gestation between January 1, 2016, and September 1, 2019. Receiver operating characteristic (ROC) curves were drawn to determine the predictive performance of CPR <1, CPR <5th or <10th percentile, and umbilical artery pulsatility (PI) >95th percentile in terms of predicting adverse neonatal outcomes.

RESULTS

Pregnant women exhibiting LOFGR who gave birth in our clinic during the study period at a mean of 38 gestational weeks (minimum 37+0; maximum 40+6 weeks); the median CPR was 1.51 [interquartile range (IQR) 1.12-1.95] and median birthweight 2,350 g (IQR 2,125-2,575 g). The CPR <5th percentile best predicted adverse neonatal outcomes [area under the curve (AUC) 0.762, 95% confidence interval (CI) 0.672-0.853, p<0.0001] and CPR <1 was the worst predictor (AUC 0.630, 95% CI 0.515-0.745, p=0.021). Of other Doppler parameters, neither the umbilical artery systole/diastole ratio nor the mid-cerebral artery to peak systolic velocity ratio (MCA-PSV) predicted adverse neonatal outcomes (AUC 0.598, 95% CI 0.480-0.598, p=0.104; AUC 0.521, 95% CI 0.396-0.521, p=0.744 respectively).

CONCLUSIONS

The CPR values below the 5th percentile better predicted adverse neonatal outcomes in pregnancies complicated by LOFGR than the UA PI and CPR <1 by using Fetal Medicine Foundation reference ranges.

Is the Cerebro-Placental Ratio Sufficient to Predict Adverse Neonatal Outcome in Small for Gestational Age Fetuses > 34 Weeks of Gestation?

Fetuses with an estimated weight (EFW) below the 10th percentile are at risk for adverse perinatal outcome and clinical management remains a challenge. We examined EFW and cerebro-placental ratio (CPR) with regard to their predictive capability in the management and outcome of such cases. Fetuses were first diagnosed as small after 34 weeks of gestation with an actual EFW below the 10th percentile at our tertiary academic center. We determined the optimum cutoff value for CPR and EFW in predicting adverse neonatal outcome. Mean gestational age at diagnosis was 36 weeks. One hundred and two cases were included in our study. We determined a CPR of 1.4 and an EFW of 2152 g to be the best cutoff value for predicting adverse fetal outcome, with an area under the curve (AUC) of 0.65 (95% CI 0.54–0.76); p = 0.009, and 0.76 (95% CI 0.66–0.86); p < 0.0001, respectively. However, when comparing EFW with CPR, EFW seems to be slightly better in predicting adverse fetal outcome in our group. While the use of CPR alone for the management of small fetuses is not sufficient, it is an important additional tool that may be of value in the clinical setting.

Longitudinal changes in maternal left atrial volume index and uterine artery pulsatility indices in uncomplicated pregnancy

BACKGROUND

Data on the relationship between longitudinal changes in maternal volume-dependent echocardiographic parameters and placentation in uncomplicated pregnancy are limited.

OBJECTIVE

This study aimed to evaluate changes in volume-dependent echocardiographic parameters in uncomplicated pregnancy to test the hypothesis of the existence of an association between volume-dependent echocardiographic parameters and Doppler ultrasound parameters of fetal circulation and the uterine artery in uncomplicated pregnancy and to establish which of the volume-dependent echocardiographic parameters best depicts volume changes and correlates best with Doppler ultrasound of fetal circulation and the uterine artery in healthy pregnancy.

STUDY DESIGN

Data from 60 healthy pregnant women were analyzed. A complete echocardiographic study was performed at 11 to 13, 20 to 22, and 30 to 32 weeks' gestation: left ventricular end-diastolic volume, early diastolic peak flow velocity, late diastolic peak flow velocity, left atrial area, and left atrial volume index were assessed. Obstetrical assessment was performed including fetal growth and uterine artery pulsatility index. Fetal well-being was assessed by umbilical and middle cerebral artery blood flow. Serum pregnancy-associated plasma protein A and free β-human chorionic gonadotropin were assessed during the routine first-trimester scan (11-13 weeks' gestation).

RESULTS

Left ventricular end-diastolic volume and left atrial area increased significantly between 11 to 13 and 20 to 22 weeks' gestation but not between 20 to 22 and 30 to 32 weeks' gestation. Left atrial volume index measured at 30 to 32 weeks' gestation correlated with uterine artery pulsatility indices in 3 trimesters. Changes in the left atrial volume index between the third and first trimesters correlated significantly with the uterine artery pulsatility index measured at 20 to 22 weeks' gestation (r=-0.345; P=.020) and at 30 to 32 weeks' gestation (r=-0.452; P=.002). Changes in the left atrial volume index between the second and first trimesters significantly correlated with the uterine artery pulsatility index measured in the first trimester (r=-0.316; P=.025).

CONCLUSION

Our study showed that in an uncomplicated pregnancy, among volume-dependent echocardiographic parameters, left atrial volume index increased between both the first and second trimesters and the second and third trimesters and correlated with parameters of Doppler ultrasound of the fetal circulation and the uterine artery. Our results expand on the previous observation on the relationship between maternal cardiovascular adaptation and placentation in women with heart diseases to the population of healthy women with uncomplicated pregnancy.