Review: Systematic review of the utility of the fetal cerebroplacental ratio measured at term for the prediction of adverse perinatal outcome

Peripartum fetal Doppler sonography and perinatal outcome: a systematic review and meta-analysis

OBJECTIVE

Systematically review and critically appraise the literature on the association between peripartum fetal Doppler sonography findings, i.e., acquired upon admission for spontaneous or induced labor, and perinatal outcome in term (37-42w) pregnancies.

METHODS

Medline, Embase, Web of Science, Cochrane Library, and clinicaltrials.gov databases were systematically searched from inception to 05/2024. Studies conducted in unselected populations of term (37-42w) pregnancies, admitted for spontaneous or induced labor, reporting the association between fetal Doppler findings and perinatal outcome, were eligible for inclusion. Study eligibility was assessed independently by two reviewers. Methodological quality was assessed using the Quality In Prognosis Studies (QUIPS)-tool. Effect estimates were pooled using random-effects meta-analyses. Summary Odds Ratios (ORs) and Mean Differences (MDs) are reported with 95% confidence intervals.

RESULTS

Thirty-seven studies, reporting on 11.505 women and neonates, were included. Fourteen studies reported on findings from the umbilical artery (UA), four on the middle cerebral artery (MCA), five on the umbilical vein (UV), and nine on the cerebroplacental ratio (CPR). An abnormal UA Doppler and CPR increased the odds of fetal distress (FD) during labor (UA: OR 3.67 [1.14, 11.78], I2 = 72% - CPR: OR 3.19 [2.68, 3.80], I2 = 0%) and subsequent operative delivery (ODFD) (UA: OR 3.65 [1.66, 8.04], I2 = 81% - CPR: OR 2.48 [1.66, 3.70], I2 = 57%). Likewise, the presence of UV pulsations was strongly associated with both outcomes (FD: OR 28.78 [11.21, 73.87], I2 = 0% - ODFD: OR 303.36 [11.11, 8279.82], I2 = 0%). Regarding neonatal outcome, an Apgar-score < 7 at 5 min and NICU admission occurred more frequently if Doppler findings were abnormal in the UA (Apgar: OR 3.65 [1.82, 7.34], I2 = 0% - NICU: OR 3.92 [2.36, 6.51], I2 = 0%), or in case of an abnormal CPR (Apgar: OR 3.64 [2.03, 6.54], I2 = 0% - NICU: OR 2.71 [1.15, 6.38], I2 = 0%). Neonatal birthweight was also lower in the presence of an abnormal UA or CPR result, with a MD of -630.61g ([-1234.29, -26.93], I2 = 80%) and -146.52g ([-285.03, -8.01], I2 = 0%) respectively. Most studies (70.3%) were at high risk of bias on one or more domains; only 11 studies had an overall low risk of bias score.

CONCLUSION

Doppler sonography in the peripartum period allows for the identification of fetuses at risk of adverse birth outcomes. Further research on optimal thresholds to define at-risk cases and subsequent management strategies is needed.

PROSPERO REGISTRATION NUMBER

CRD42023413264.

Placental biomarker and fetoplacental Doppler abnormalities are strongly associated with placental pathology in pregnancies with small-for-gestational-age fetus: prospective study

OBJECTIVE

Placental dysfunction can result in small-for-gestational age (SGA) or fetal growth restriction (FGR). The aim of this prospective cohort study was to assess the association of the cerebroplacental ratio (CPR) and other more conventional fetoplacental Doppler indices, circulating placental growth factor (PlGF) levels and soluble fms-like tyrosine kinase-1 (sFlt-1)/PlGF ratio, with specific placental abnormalities in a large cohort of pregnancies with an SGA/FGR fetus.

METHODS

This was a prospective cohort study of singleton pregnancies with a SGA/FGR fetus conducted at the Centre for Maternal and Fetal Medicine at the Mater Mother's Hospital, Queensland, Australia. Multivariable logistic regression with adjustment for pre-eclampsia was used to evaluate the effect of CPR < 5th centile, umbilical artery Doppler abnormality (defined as umbilical artery (UA) pulsatility index (PI) > 95th centile, or absent or reversed end-diastolic flow), mean uterine artery (UtA) PI > 95th centile and abnormal placental biomarkers (PlGF level < 100 ng/L and sFlt-1/PlGF ratio > 5.78 if gestational age < 28 weeks or > 38 if gestational age ≥ 28 weeks) on the following placental abnormalities, classified based on the Amsterdam Placental Workshop Group Consensus criteria: placental maternal vascular malperfusion (MVM), fetal vascular malperfusion (FVM), villitis of unknown etiology (VUE), chronic histiocytic intervillositis (CHI) and delayed villous maturation (DVM).

RESULTS

Among the 367 women included in this study, MVM was present in 159 (43.3%) placentae, FVM in 20 (5.4%), VUE in 49 (13.4%), DVM in 19 (5.2%) and CHI in six (1.6%). Compared to SGA controls with normal fetoplacental Doppler and placental biomarkers, CPR < 5th centile (adjusted odds ratio (aOR), 3.17 (95% CI, 1.95-5.16); P < 0.001), abnormal UA Doppler (aOR, 2.97 (95% CI, 1.80-4.90); P < 0.001) and mean UtA-PI > 95th centile (aOR, 5.42 (95% CI 2.75-10.70); P < 0.001) were associated with higher odds of placental abnormality. The odds of MVM specifically were significantly higher when CPR < 5th centile (aOR, 2.47 (95% CI, 1.64-4.33); P < 0.001), abnormal UA Doppler (aOR, 3.13 (95% CI, 1.91-5.12); P < 0.001) or mean UtA-PI > 95th centile (aOR, 4.01 (95% CI, 2.25-7.13); P < 0.001) was present. The odds of placental abnormality were also significantly higher if PlGF levels were < 100 ng/L (aOR, 3.66 (95% CI, 2.22-6.06); P < 0.001) or the sFlt-1/PlGF ratio was elevated (aOR, 3.74 (95% CI, 2.17-6.43); P < 0.001). The odds of MVM were also higher in women with PlGF < 100 ng/L (aOR, 2.89 (95% CI, 1.72-4.85); P < 0.001) and elevated sFlt-1/PlGF ratio (aOR, 3.15 (95% CI, 1.83-5.45); P < 0.001).

CONCLUSION

In pregnancies with SGA/FGR fetus, mean UtA-PI > 95th centile, abnormal UA Doppler, CPR < 5th centile, PlGF < 100 ng/L and elevated sFlt-1/PlGF ratio were all strongly associated with placental abnormality, particularly MVM. © 2025 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Prevalence and Doppler Indices of Late-Onset Fetal Growth Restriction at a Single University Hospital in Southern Thailand

OBJECTIVES

To evaluate the prevalence of late-onset fetal growth restriction (FGR), and comprehensively assess maternal and fetal Doppler indices by comparing the Doppler measurements of the uterine artery (UtA), umbilical artery (UA), umbilical vein (UV), middle cerebral artery (MCA), and ductus venosus (DV) between normal and FGR groups.

METHODS

This prospective study enrolled 306 singleton pregnant women at ≥ 32 weeks' gestation between June 1, 2023 and April 30, 2024. Fetal biometry and Doppler indices were measured via transabdominal ultrasonography by a single operator. The Mann-Whitney U test was used for statistical comparison.

RESULTS

Late-onset FGR prevalence was 4.9% (15/306). The FGR group had a significantly higher UtA pulsatility index (PI) and lower cerebroplacental ratio (CPR), cerebral-placental-uterine ratio (CPUR), and UV blood flow normalized for fetal abdominal circumference (UVBF/AC) compared to the normal group.

CONCLUSION

Late-onset FGR prevalence was approximately 5%. The higher UtA-PI and lower CPR, CPUR, and UVBF/AC in the FGR group indicated mild placental insufficiency.

Reproducibility of fetal ultrasound doppler parameters used for growth assessment

OBJECTIVES

To produce standards of references for quality control and assess the reproducibility of fetal ultrasound Doppler measurements commonly used for blood flow assessment in fetal growth.

METHODS

Women with singleton normal pregnancies were prospectively recruited at University College London Hospital, UK, between 24 and 41 weeks. Umbilical artery (UA), middle cerebral artery (MCA), and their pulsatility indices (PI), resistance indices (RI) and ratios such as cerebro-placental (CPR) and umbilical cerebral ratio (UCR) were obtained twice by two sonographers in training or after completion of training, blind to each other's measurements. Bland-Altman plots were generated, the mean differences and 95% limits of agreement (LOA) were calculated to assess intra- and interobserver reproducibility. Values were expressed as absolute values or as z-score.

RESULTS

One hundred ten women were recruited. Overall reproducibility was variable for absolute values and highly variable for z-scores, independently from vessel sampled, index or ratio used, intra- or interobserver reproducibility. The widest absolute values of 95% LOA were 0.3 for UA PI, 0.7 for MCA PI, 0.9 for CPR and 0.3 for UCR, respectively. Regarding z-score, the widest 95% LOA were 1.9 for UA PI, 2.1 for CPR and 1 for UCR. Reproducibility was slightly better for intra- compared with interobserver variability. There was significant difference in z-score reproducibility between MCA peak systolic velocity and CPR vs UCR.

CONCLUSIONS

Reference standards of reproducibility of fetal Doppler parameters are produced for standardization and quality-control purposes. Overall, the reproducibility for fetal Doppler parameters was variable independently from vessel sampled, Doppler index (PI or RI) or ratio used, intra- and interobserver comparison. UCR was the most reproducible parameter which should be recommended, together with UA PI, for clinical use and in research studies on fetal growth.

The importance of the cerebro-placental ratio at term for predicting adverse perinatal outcomes in appropriate for gestational age fetuses

OBJECTIVES

This study investigates the relationship between the cerebro-placental ratio (CPR) measured at 40+0 weeks' gestation and perinatal outcomes to determine a CPR cut-off that may justify induction of labor at term in appropriately grown fetuses (AGA). Although CPR is used for monitoring growth-restricted fetuses, its role in guiding labor induction decisions for AGA pregnancies at term remains unclear.

METHODS

A retrospective cohort study was conducted using data from 491 singleton pregnancies with intended vaginal deliveries between 2015 and 2021. CPR was assessed at the actual estimated date of delivery (40+0 weeks' gestation). Adverse pregnancy outcome (APO) as the primary endpoint was defined by admission to neonatal intensive care unit (NICU), umbilical cord blood pH<7.1, 5-min APGAR<7 or interventions-due-to-fetal-distress during labor (IDFD=vaginal-operative delivery or emergency caesarean section).

RESULTS

APO nearly doubled (adjOR 1.7; CI 1.007-2.905) when CPR was below our calculated cut-off of 1.269 (18.4 vs. 32.3 %, p=0.002) and NICU admissions (4.8 vs. 11.1 %, p=0.020) and IDFD (12.5 vs. 21.2 %, p=0.027) significantly increased. The positive predictive value for the presence of APO using our cut-off was 32.4 %, and the negative predictive value 81.6 %.

CONCLUSIONS

Our data confirm a predictive value of a reduced CPR at term with impaired perinatal outcome. The cut-off of CPR<1.269 may guide decision-making regarding induction of labor. Further prospective studies are needed to confirm these findings.

Effect of the maternal sleep disturbances and obstructive sleep apnea on feto-placental Doppler: A systematic review

Literature evidenced an association of maternal sleep disturbances and maternal obstructive sleep apnea with significant obstetric complications. Moreover, the maternal sleep disturbances effect on feto-placental circulation had not been extensively examined. Our objective is to explore the possible maternal sleep disturbances impact on the feto-placental indices evaluated through the Doppler study. A systematic review of the following databases was performed: PubMed, EMBASE, Cochrane Library and Google Scholar from the beginning to June 2024. Only studies that enrolled pregnant women with signs and symptoms of maternal sleep disturbances or obstructive sleep apnea diagnosis, which analysed the feto-placental Doppler parameters, were considered eligible (PROSPERO ID: CRD42024553926). We included a total of four studies with 1715 cases of pregnant women. Various instrumental and non-instrumental diagnostic methods were adopted for detection of maternal sleep disturbances. The ultrasound exam was performed mainly in the third trimester of pregnancies, and all the studies explored the uterine Doppler parameters. Only two studies explore the foetal Doppler parameters. Only one study disclosed that maternal sleep disturbances are related to altered uterine Doppler indices with probable placental dysfunction. This review did not evidence a significant influence of maternal sleep disturbances and obstructive sleep apnea on foetal Doppler indices. Moreover, one large prospective study showed a possible impact of maternal sleep disturbances on uterine Doppler with a potential impairment of the placentation function. Additional studies with detailed data and larger samples are needed to throw light on this relationship and its impact on the foetal outcomes.

Prediction of low birth weight from fetal ultrasound and clinical characteristics: a comparative study between a low- and middle-income and a high-income country

INTRODUCTION

Adverse perinatal outcomes (APO) pose a significant global challenge, particularly in low- and middle-income countries (LMICs). This study aims to analyse two cohorts of high-risk pregnant women for APO to comprehend risk factors and improve prediction accuracy.

METHODS

We considered an LMIC and a high-income country (HIC) population to derive XGBoost classifiers to predict low birth weight (LBW) from a comprehensive set of maternal and fetal characteristics including socio-demographic, past and current pregnancy information, fetal biometry and fetoplacental Doppler measurements. Data were sourced from the FeDoC (Fetal Doppler Collaborative) study (Pakistan, LMIC) and theIMPACT (Improving Mothers for a Better PrenAtal Care Trial) study (Spain, HIC), and included 520 and 746 pregnancies assessed from 28 weeks gestation, respectively. The models were trained on varying subsets of the mentioned characteristics to evaluate their contribution in predicting LBW cases. For external validation, and to highlight potential differential risk factors for LBW, we investigated the generalisation of these models across cohorts. Models' performance was evaluated through the area under the curve (AUC), and their interpretability was assessed using SHapley Additive exPlanations.

RESULTS

In FeDoC, Doppler variables demonstrated the highest value at predicting LBW compared with biometry and maternal clinical data (AUCDoppler, 0.67; AUCClinical, 0.65; AUCBiometry, 0.63), and its combination with maternal clinical data yielded the best prediction (AUCClinical+Doppler, 0.71). In IMPACT, fetal biometry emerged as the most predictive set (AUCBiometry, 0.75; AUCDoppler, 0.70; AUCClinical, 0.69) and its combination with Doppler and maternal clinical data achieved the highest accuracy (AUCClinical+Biometry+Doppler, 0.81). External validation consistently indicated that biometry combined with Doppler data yielded the best prediction.

CONCLUSIONS

Our findings provide new insights into the predictive role of different clinical and ultrasound descriptors in two populations at high risk for APO, highlighting that different approaches are required for different populations. However, Doppler data improves prediction capabilities in both settings, underscoring the value of standardising ultrasound data acquisition, as practiced in HIC, to enhance LBW prediction in LMIC. This alignment contributes to bridging the health equity gap.

Term planned delivery based on fetal growth assessment with or without the cerebroplacental ratio in low-risk pregnancies (RATIO37): an international, multicentre, open-label, randomised controlled trial

BACKGROUND

The cerebroplacental ratio is associated with perinatal mortality and morbidity, but it is unknown whether routine measurement improves pregnancy outcomes. We aimed to evaluate whether the addition of cerebroplacental ratio measurement to the standard ultrasound growth assessment near term reduces perinatal mortality and severe neonatal morbidity, compared with growth assessment alone.

METHODS

RATIO37 was a randomised, open-label, multicentre, pragmatic trial, conducted in low-risk pregnant women, recruited from nine hospitals over six countries. The eligibility criteria were designed to be broad; participants were required to be 18 years or older, with an ultrasound-dated confirmed singleton pregnancy in the first trimester, an alive fetus with no congenital malformations at the routine second-trimester ultrasound, an absence of adverse medical or obstetric history, and the capacity to give informed consent. Women were randomly assigned in a 1:1 ratio (block size 100) using a web-based system to either the concealed group or revealed group. In the revealed group, the cerebroplacental ratio value was known by clinicians, and if below the fifth centile, a planned delivery after 37 weeks was recommended. In the concealed group, women and clinicians were blinded to the cerebroplacental ratio value. All participants underwent ultrasound at 36 + 0 to 37 + 6 weeks of gestation with growth assessment and Doppler evaluation. In both groups, planned delivery was recommended when the estimated fetal weight was below the tenth centile. The primary outcome was perinatal mortality from 24 weeks' gestation to infant discharge. The study is registered at ClinicalTrials.gov (NCT02907242) and is now closed.

FINDINGS

Between July 29, 2016, and Aug 3, 2021, we enrolled 11 214 women, of whom 9492 (84·6%) completed the trial and were eligible for analysis (4774 in the concealed group and 4718 in the revealed group). Perinatal mortality occurred in 13 (0·3%) of 4774 pregnancies in the concealed group and 13 (0·3%) of 4718 in the revealed group (OR 1·45 [95% CI 0·76-2·76]; p=0·262). Overall, severe neonatal morbidity occurred in 35 (0·73%) newborns in the concealed group and 18 (0·38%) in the revealed group (OR 0·58 [95% CI 0·40-0·83]; p=0·003). Severe neurological morbidity occurred in 13 (0·27%) newborns in the concealed group and nine (0·19%) in the revealed group (OR 0·56 [95% CI 0·25-1·24]; p=0·153). Severe non-neurological morbidity occurred in 23 (0·48%) newborns in the concealed group and nine (0·19%) in the revealed group (0·58 [95% CI 0·39-0·87]; p=0·009). Maternal adverse events were not collected.

INTERPRETATION

Planned delivery at term based on ultrasound fetal growth assessment and cerebroplacental ratio at term was not followed by a reduction of perinatal mortality although significantly reduced severe neonatal morbidity compared with fetal growth assessment alone.

FUNDING

La Caixa foundation, Cerebra Foundation for the Brain Injured Child, Agència per la Gestió d'Ajuts Universitaris i de Recerca, and Instituto de Salud Carlos III.

Correlation between cerebroplacental doppler ratio and neonatal respiratory disorders: A reference marker of fetal lung maturation

OBJECTIVE

The aim of this study was to investigate the role of cerebroplacental ratio (CPR) in the final prenatal care for neonatal respiratory diseases and to analyze the risk of relevant factors associated with neonatal respiratory disorders.

METHODS

A prospective cohort study of 795 singleton pregnancies was conducted. The pulsatility indices (PI) of the umbilical artery (UA) and the middle cerebral artery (MCA) were measured, and the MCA to UA ratio (CPR) was determined. The severity of the case is determined by whether or not the newborn has respiratory problems. Compare the CPR correlation between the two groups and examine the illness prediction factors through a binary logistic regression method.

RESULTS

Of the 795 participants, 124 had neonatal respiratory disorders. The mean values of CPR between neonatal respiratory diseases group and control group were 1.78±0.6, 1.97±0.9, respectively (P < 0.001). Maternal age, abortion history, cesarean section history, placental thickness, placental maturity, and amniotic fluid index (AFI) were determined to have no significant link between the two groups after comparison analysis (P > 0.05). It could be found that compared with the control group, CPR MoM indicators of neonatal respiratory distress syndrome, neonatal pneumonia and wet lung disease all show significant decreases. In binary logistic regression analysis, among the variables included in the model, CPR (OR:2.90, P = 0.015), fetal heart monitoring (OR:5.26, P < 0.001), delivery mode (OR:2.86, P < 0.001) and gestational age of delivery (OR:0.92, P < 0.001) were statistically significant in both groups.

CONCLUSION

The findings of this study showed that infant respiratory problems were substantially related to CPR value. The correlation indicates that CPR was a powerful reference marker for respiratory disorders.

Diastolic deceleration area in the fetal MCA: a new Doppler parameter

Objective: Doppler velocimetry has been widely used throughout the years as a valuable tool in the follow-up and prognosis of various pregnancy complications. Numerous Doppler indices have been introduced to qualitatively describe fetal blood flow. Currently, the Pulsatility index (PI) is the most widely used index for this purpose. In current clinical practice, middle cerebral artery (MCA) PI measurement is commonly used to assess fetal well-being, especially in late-onset fetal growth restriction (FGR). However, existing evidence suggests that MCA PI alone is inferior to the ratio between MCA and umbilical artery (UA) pulsatility indices in predicting adverse perinatal and neonatal outcomes. When comparing normal and abnormal MCA Doppler waveforms, it is evident that most changes appear in the diastolic part of the heart cycle. Therefore, the PI, which contains elements from both systole (peak systolic velocity-PSV) and diastole (end-diastolic velocity), may not be the most effective tool for quantifying fetal brain sparing (BS).Methods: We hypothesize that another measurement modality that focuses predominantly on the diastole could be more efficient for evaluating the amount of vasodilatation. In ultrasound velocimetry of larger blood vessels, there is a well-known phenomenon called "dicrotic notch" (DN), which appears on the declining part of each Doppler waveform and can be used to precisely pinpoint the end of systole and the start of diastole. We hypothesized that the extent of cerebral vasodilation can be more accurately assessed by measuring the area between the dicrotic notch (DN) and the end-diastolic velocity (which we refer to as the "diastolic deceleration area-DDA"). In this study, we introduced a new Doppler parameter along with a rationale for DDA measurement in the fetal MCA. We also defined third-trimester nomograms and provided a preliminary assessment of the correlation between DDA and fetal oxygen deficiency.Results: Our findings suggest that the DDA may serve as an independent instrument for identifying hypoxia during late pregnancy, either on its own or in conjunction with other Doppler and cardiotocography modalities.Conclusion: However, before incorporating DDA into clinical practice, it is crucial to conduct further research and validation studies with larger sample sizes and more diverse populations. This would help assess the generalizability of the results and establish optimal cutoff points for DDA in various clinical settings. It is also important to prospectively study the role of DDA in early- and late-onset fetal growth restriction (FGR), Rh-isoimmunization/anemia, preeclampsia, gestational diabetes, and other pregnancy complications. In fact, we believe that the concept of measuring specific areas in arterial Doppler velocimetry indices could have significant implications not only in fetal medicine and obstetrics, but also in other areas of human and veterinary medicine.

Routine third trimester ultrasonography in predicting adverse perinatal outcomes: a prospective cohort study at a tertiary-care hospital in Eastern India

AIMS

Fetal growth restriction (FGR) may go undetected in the antenatal period with subjective clinical evaluation, and there is a growing propensity to perform a third-trimester scan, especially in the developed countries. The literature on the importance of the same in developing countries like ours, is scant. Hence, this study was undertaken to evaluate the role of routine third-trimester ultrasonography along with Doppler in predicting adverse perinatal outcome.

METHODS

A prospective cohort study was conducted at a tertiary-care hospital, in which routine third-trimester ultrasonography was performed for 265 antenatal women, and included estimation of amniotic fluid index (AFI), estimated fetal-weight (EFW), and cerebroplacental ratio (CPR). Women were categorized as having normal parameters or having at least one abnormal parameter. Post-natal adverse perinatal outcomes including low birth-weight, hypoglycemia, poor Apgar scores, prolonged hospital stay, need for ventilatory support, neonatal asphyxia, neonatal sepsis and early neonatal death were recorded. Prediction analyses for sensitivity, specificity, positive and negative predictive values were done. Receiver Operating Characteristic (ROC) curves were plotted for threshold for each parameter for adverse outcome.

RESULTS

Out of 260 women that were analyzed, 47.5% had no clinically identifiable risk factors, and 52.5% had at least one abnormal parameter. Sensitivity and negative predictive value for adverse outcome were highest for composite ultrasound finding (85.4% and 90.4% respectively). Specificity, positive predictive value and diagnostic accuracy were highest for CPR (97.8%, 86.7% and 76.9% respectively).

CONCLUSION

Routine third trimester ultrasonography, including Doppler, can help in risk-stratification of otherwise clinically low-risk pregnancies.

Association of maternal, fetal and labor variables with a low Apgar score in the fifth minute in term pregnancy: a case-control study

PURPOSE

To search for maternal, labor-related and fetal variables associated with low Apgar in the fifth minute in term pregnancy.

METHODS

A retrospective case-control study with term births was conducted in a public teaching hospital from 2013 to 2020. Cases were term births with Apgar score less than 7 in the fifth minute, and controls, the next one or two births following a case, with Apgar of 7 or more. Non-cephalic presentations, multiples and malformations were excluded. We accessed 100 cases and 190 controls. We considered significant values of p < 0.05.

RESULTS

Were accessed 27 variables which could be risk factors, from which 12 were associated with the outcome. We found a protective effect of prelabor cesarean for the outcome, odds ratio (OR) 0.38, p = 0.013. Consequently, we conducted two sets of analyses: in the whole group and in the group of laboring women. The values of OR were in general greater in the group of laboring women, compared with the whole group. We conducted multivariate analysis within the group of women in labor. The variables which fitted best in the model were nulliparity, male sex of the fetus, less than six prenatal visits and abnormal cardiotocography; all remained significant. An association of rupture of membranes more than 360 min with the outcome, even after controlling fpr duration of labor, was found; adjusted OR 2.45, p = 0.023.

CONCLUSION

Twelve variables were associated with the outcome. Prelabor cesarean had a protective effect. The time of ruptured membranes was associated with low Apgar.

Predictive utility of the fetal cerebroplacental ratio for hypoxic ischaemic encephalopathy, severe neonatal morbidity and perinatal mortality in late-preterm and term infants

AIMS

The aim of this study was to evaluate the association of a low cerebroplacental ratio (CPR) with hypoxic ischaemic encephalopathy (HIE), severe neonatal morbidity (SNM) and perinatal mortality (PNM).

METHODS

This was a retrospective cohort study of late-preterm and term births at Mater Mothers' Hospital, Brisbane, between 2016 and 2020. Study outcomes were HIE, PNM and SNM (a composite of severe acidosis, Apgar score less than four at 5 min, severe respiratory distress or need for significant cardiopulmonary resuscitation at birth). Univariate and multivariable logistic regressions were used to determine if a low CPR was associated with HIE, SNM or PNM.

RESULTS

A total of 51 870 births met the inclusion criteria. Of these, 216 (0.42%) were complicated by HIE, 10 224 (19.7%) had SNM and 251 (0.48%) had PNM. Rates of low CPR (<10th and <5th centile) were significantly higher in the SNM cohort (20.1 and 13.2%, respectively) and PNM cohort (21.1 and 15.1%, respectively) compared to the overall cohort. A low CPR was associated with significantly increased adjusted odds for SNM but not for HIE or PNM. The area under the receiver operating characteristic curve for CPR <10th centile was greatest for SNM (0.768) and lowest for HIE (0.595). Predictive margins of a low CPR for HIE, SNM and PNM were significant only for SNM at late-preterm gestations.

CONCLUSIONS

A low CPR is associated with increased odds of SNM in infants born >34 weeks' gestation but not for HIE or PNM.

Uterine artery Doppler in early labor and perinatal outcome in low-risk term pregnancy: prospective multicenter study

OBJECTIVE

The prediction of adverse perinatal outcomes in low-risk pregnancies is poor, mainly owing to the lack of reliable biomarkers. Uterine artery (UtA) Doppler is closely associated with placental function and may facilitate the peripartum detection of subclinical placental insufficiency. The objective of this study was to evaluate the association of mean UtA pulsatility index (PI) measured in early labor with obstetric intervention for suspected intrapartum fetal compromise and adverse perinatal outcome in uncomplicated singleton term pregnancies.

METHODS

This was a prospective multicenter observational study conducted across four tertiary maternity units. Low-risk term pregnancies with spontaneous onset of labor were included. The mean UtA-PI was recorded between uterine contractions in women admitted for early labor and converted into multiples of the median (MoM). The primary outcome of the study was the occurrence of obstetric intervention, i.e. Cesarean section or instrumental delivery, for suspected intrapartum fetal compromise. Secondary outcomes were the occurrence of adverse perinatal outcomes, including 5-min Apgar score < 7, low cord arterial pH, raised cord arterial base excess, admission to the neonatal intensive care unit (NICU) and postnatal diagnosis of small-for-gestational-age fetus. Composite adverse perinatal outcome was defined as the occurrence of at least one of the following: acidemia in the umbilical artery, defined as pH < 7.10 and/or base excess > 12 mmol/L, 5-min Apgar score < 7 or admission to the NICU.

RESULTS

Overall, 804 women were included, of whom 40 (5.0%) had abnormal mean UtA-PI MoM. Women who had an obstetric intervention for suspected intrapartum fetal compromise were more frequently nulliparous (72.2% vs 53.6%; P = 0.008), had a higher frequency of increased mean UtA-PI MoM (13.0% vs 4.4%; P = 0.005) and had a longer duration of labor (456 ± 221 vs 371 ± 192 min; P = 0.01). On logistic regression analysis, only increased mean UtA-PI MoM (adjusted odds ratio (aOR), 3.48 (95% CI, 1.43-8.47); P = 0.006) and parity (aOR, 0.45 (95% CI, 0.24-0.86); P = 0.015) were independently associated with obstetric intervention for suspected intrapartum fetal compromise. Increased mean UtA-PI MoM was associated with a sensitivity of 0.13 (95% CI, 0.05-0.25), specificity of 0.96 (95% CI, 0.94-0.97), positive predictive value of 0.18 (95% CI, 0.07-0.33), negative predictive value of 0.94 (95% CI, 0.92-0.95), positive likelihood ratio of 2.95 (95% CI, 1.37-6.35) and negative likelihood ratio of 0.91 (95% CI, 0.82-1.01) for obstetric intervention for suspected intrapartum fetal compromise. Pregnancies with increased mean UtA-PI MoM also showed a higher incidence of birth weight < 10th percentile (20.0% vs 6.7%; P = 0.002), NICU admission (7.5% vs 1.2%; P = 0.001) and composite adverse perinatal outcome (15.0% vs 5.1%; P = 0.008).

CONCLUSION

Our study, conducted in a cohort of low-risk term pregnancies enrolled in early spontaneous labor, showed an independent association between increased mean UtA-PI and obstetric intervention for suspected intrapartum fetal compromise, albeit with moderate capacity to rule in, and poor capacity to rule out, this condition. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Prognostic Accuracy of Antenatal Doppler Ultrasound Measures in Predicting Adverse Perinatal Outcomes for Pregnancies Complicated by Diabetes: A Systematic Review

OBJECTIVE

This study aimed to assess the prognostic accuracies of Doppler ultrasound measures in predicting adverse perinatal outcomes for pregnancies complicated with preexisting or gestational diabetes mellitus.

DATA SOURCES

An online database search of MEDLINE, Cochrane, Embase, CINAHL, Scopus, and Emcare from inception to April 2022 was conducted.

STUDY ELIGIBILITY CRITERIA

Studies reporting singleton, nonanomalous fetuses of women with either preexisting (type 1 or 2 diabetes mellitus) or gestational diabetes mellitus during pregnancy were included. In addition, the included studies assessed cerebroplacental ratio and middle cerebral artery and/or umbilical artery pulsatility index in the prediction of either: preterm birth, cesarean delivery for fetal distress, APGAR (Appearance, Pulse, Grimace, Activity, and Respiration) score <7 at 5 minutes, neonatal intensive care unit admission (>24 hours), acute respiratory distress syndrome, jaundice, hypoglycemia, hypocalcemia, or neonatal death.

METHODS

The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed and 610 articles were identified, of which 15 were included. Two authors independently extracted prognostic data from each article and assessed the study applicability and risk of bias using the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2) scoring criteria.

RESULTS

A total of 15 studies were included in the review and comprised prospective (n=10; 66%) and retrospective (n=5; 33%) cohorts. Sensitivity and positive predictive values varied widely across each Doppler measurement. Umbilical artery sensitivities were higher than those of cerebroplacental ratio and middle cerebral artery for hypoglycemia, jaundice, neonatal intensive care unit admission, respiratory distress, and preterm birth. Cerebroplacental ratio was the most reported index test; however, prognostic accuracy was worse than that of umbilical artery and middle cerebral artery Doppler across all adverse perinatal outcomes. Significant risk of bias was present in 14 (94%) studies, with substantial heterogeneity observed across studies in terms of study design and outcomes assessed.

CONCLUSION

Abnormal umbilical artery pulsatility index may be of more clinical value in predicting adverse perinatal outcomes compared with cerebroplacental ratio and middle cerebral artery pulsatility index in diabetic pregnancies. Further evaluation of umbilical artery Doppler measurements in diabetic pregnancies using standardized variables across studies is required for broader clinical application. The significant association between abnormal Doppler measurement and hypoglycemia may warrant further investigation.

Maternal, obstetric, and fetal Doppler characteristics in a high-risk population: prediction of adverse perinatal outcomes and of cesarean section due to intrapartum fetal compromise

Objective

To evaluate the capacity of fetal Doppler, maternal, and obstetric characteristics for the prediction of cesarean section due to intrapartum fetal compromise (IFC), a 5-min Apgar score < 7, and an adverse perinatal outcome (APO), in a high-risk population.

Materials and Methods

This was a prospective cohort study involving 613 singleton pregnant women, admitted for labor induction or at the beginning of spontaneous labor, who underwent Doppler ultrasound within the last 72 h before delivery. The outcome measures were cesarean section due to IFC, a 5-min Apgar score < 7, and any APO.

Results

We found that maternal characteristics were neither associated with nor predictors of an APO. Abnormal umbilical artery (UA) resistance index (RI) and the need for intrauterine resuscitation were found to be significant risk factors for cesarean section due to IFC (p = 0.03 and p < 0.0001, respectively). A UA RI > the 95th percentile and a cerebroplacental ratio (CPR) < 0.98 were also found to be predictors of cesarean section due to IFC. Gestational age and a UA RI > 0.84 were found to be predictors of a 5-min Apgar score < 7 for newborns at < 29 and ≥ 29 weeks, respectively. The UA RI and CPR presented moderate accuracy in predicting an APO, with areas under the ROC curve of 0.76 and 0.72, respectively.

Conclusion

A high UA RI appears to be a significant predictor of an APO. The CPR seems to be predictive of cesarean section due to IFC and of an APO in late preterm and term newborns.

Evaluación integrada del bienestar en un feto apropiado para la edad gestacional (AGA) e insuficiencia placentaria aguda debido a corioamnionitis histológica: Reporte de caso

Introducción. La insuficiencia vascular útero placentaria aguda es una causa de desenlace fetal adverso en fetos con crecimiento adecuado para la edad gestacional. Caso clínico. Paciente de 24 años, con 37 semanas de edad gestacional acude al Instituto Nacional Materno Perinatal de Lima, Perú, por referir escaso sangrado vía vaginal. En la evaluación clínica, se encontró una PA 90/60 mmHg, altura uterina 32 cm, latidos cardiacos fetales en 152. A la evaluación ecográfica, a 1 hora de la admisión se reportó feto de 2902 gramos (percentil 34 Hadlock), un Perfil Biofísico Fetal 6/8 por movimientos corporales disminuidos, Índice de líquido amniótico 11cm, placenta fúndica posterior grado III, IP Doppler de Arteria Cerebral Media 1.18, IP Doppler de la arteria umbilical 0.56, IP ductus venoso 0.26 e Istmo Aórtico con diástole ausente. La prueba estresante a las 3 horas de la admisión fue reportada en 5 puntos con movimientos fetales disminuidos, variabilidad disminuida y aceleraciones ausentes. Se indicó cesárea de emergencia obteniéndose recién nacido masculino de 2846 gr, talla 47.5 cm, Apgar 8 – 9. Se encontró líquido meconial de aspecto sanguinolento oscuro. Al corte de la placenta, se observó parénquima con infartos vellosos: recientes 10% y antiguos 5%. Vellosidades coriales hipoplásicas con espacios intervellosos amplios e infiltrado inflamatorio agudo en corion y amnios, correspondientes a Corioamnionitis aguda y funisitis aguda en el cordón umbilical. Conclusiones. La vigilancia integrada de fetos AEG permiten detectar a fetos en riesgo de desenlace adverso por una insuficiencia placentaria aguda secundaria a corioamnionitis histológica o subclínica.

Added prognostic value of Doppler ultrasound for adverse perinatal outcomes: A pooled analysis of three cohort studies

BACKGROUND

Fetal growth restriction (FGR) is an obstetric complication associated with adverse perinatal outcomes. Doppler ultrasound can improve perinatal outcomes through monitoring at-risk fetuses and helping time delivery.

AIM

To investigate the prognostic value of different Doppler ultrasound measurements for adverse perinatal outcomes.

MATERIALS

Individual participant data.

METHODS

We performed a pooled analysis on individual participant data. We compared six prognostic models using multilevel logistic regression, where each subsequent model added a new variable to a base model that included maternal characteristics. Estimated fetal weight (EFW) and four Doppler ultrasound measurements were added in turn: umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI), cerebroplacental ratio (CPR), and mean uterine artery pulsatility index (mUtA PI). The primary outcome was a composite adverse perinatal outcome, defined as perinatal mortality, emergency caesarean delivery for fetal distress, or neonatal admission. Discriminative ability was quantified with area under the curve (AUC).

RESULTS

Three data sets (N = 3284) were included. Overall, the model that included EFW and UA PI improved AUC from 0.650 (95% CI 0.624-0.676) to 0.673 (95% CI 0.646-0.700). Adding more ultrasound measurements did not improve further the discriminative ability. In subgroup analysis, the addition of EFW and UA PI improved AUC in both preterm (AUC from 0.711 to 0.795) and small for gestational age pregnancies (AUC from 0.729 to 0.770), but they did not improve the models in term delivery or normal growth subgroups.

CONCLUSIONS

Umbilical artery pulsatility index added prognostic value for adverse perinatal outcomes to the already available information, but the combination of other Doppler ultrasound measurements (MCA PI, CPR or UtA PI) did not improve further prognostic performance.

Pregnancy, birth and neonatal outcomes associated with reduced fetal movements: A systematic review and meta-analysis of non-randomised studies

PROBLEM

Maternal perception of reduced fetal movements (RFM) is identified as an important alarm signal for possible risk of impending adverse perinatal outcomes.

BACKGROUND

Perinatal outcomes associated with RFM are increasingly being investigated in non-randomised studies with several associated outcomes, including stillbirth, preterm birth, fetal growth restriction and neonatal death being reported. Findings from studies, however, are conflicting.

AIM

To synthesise the findings of published studies regarding pregnancy, birth and neonatal outcomes in women who presented with RFM.

METHODS

PubMed, EMBASE, CINAHL complete, Maternity and Infant Care, PsycINFO, and Science Citation Index databases were searched up to 8th July 2021 and updated again on 8th September 2022. Non-randomised studies involving pregnant women ≥24 weeks' gestation, who presented with a primary complaint of RFM compared to women who did not present with RFM were included. Data were meta-analysed using a random-effects model and presented as Odds Ratios (OR) or Standard Mean Differences (SMD) with 95% Confidence Intervals (CI).

FINDINGS

Thirty-nine studies were included. Women with RFM had increased odds of stillbirth (OR 3.44, 95% CI 2.02-5.88) and small for gestational age (OR 1.37, 95% CI 1.16-1.61) when compared with women who did not have RFM. Associations were also found for induction of labor, instrumental birth and caesarean section but not for preterm birth (OR 0.92, 95% CI 0.71-1.19) or neonatal death (OR 0.99; 95% CI 0.52-1.90).

CONCLUSION

This review revealed that RFM is associated with increased odds of stillbirth, small for gestational age, induction of labor, instrumental birth and caesarean section but not preterm birth or neonatal death.

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.

Systematic review evaluating the efficacy of the cerebroplacental ratio (CPR) in saving babies lives

Introduction

The aim of this systematic review is to critically assess the efficacy of the cerebroplacental ratio performed in the third trimester at predicting adverse perinatal outcomes and reducing stillbirth rates.

Method

The literature search was performed using CINAHL, EMBASE, EMCARE, MEDLINE and PubMed including systematic reviews, retrospective and prospective studies from inception until July 2020 utilising the PRISMA checklist and flowchart. Data displaying sensitivities, specificity and odds ratios (OR) to include 95% confidence interval (CI) were extracted and synthesised.

Findings

Initially, 1226 studies were identified, and nine studies met the inclusion criteria. Sample sizes ranged from 491 to 9772 pregnancies. The cerebroplacental ratio had the strongest diagnostic accuracy of all of the independent variables for detecting fetal demise (mean sensitivity and specificity; 79% and 78%). The cerebroplacental ratio, however, did not perform as favourably at predicting operative delivery (mean sensitivity and specificity; 59% and 82%) or anticipating admission to the neonatal intensive care unit (mean sensitivity and specificity; 55% and 74%).

Discussion

The results from this study showed that the cerebroplacental ratio within third trimester pregnancies has been proven to have moderate to high diagnostic value when detecting adverse perinatal outcomes, in particular fetal demise.

Conclusion

Cerebroplacental ratio has the potential as a diagnostic tool to reduce adverse perinatal outcomes, in particular fetal demise and help reduce stillbirth rates. The main study limitation involved heterogeneity within the included studies, in particular with a regard to blinding.

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.

New Markers for Placental Dysfunction at Term - Potential for More

The remaining placental reserve capacity at term plays a decisive role in the perinatal morbidity of mother and child. Considering advances made in the field of fetal monitoring, the routine examination methods currently used at term or late term may be insufficient to detect subclinical placental dysfunction (PD). The aim of this study is to offer an up-to-date, narrative review of the literature in the context of detecting PD at term using complementary ultrasound markers and biomarkers. Parameters of fetomaternal Doppler ultrasound and fetal cardiac function, as well as (anti-)angiogenic factors in maternal serum are potential PD markers. These may help identify patients that may benefit from an elective, early induction of labor at term, thereby potentially reducing morbidity and mortality. However, their value in terms of the optimal date of delivery must first be determined in randomized controlled trials on a large number of cases.

Modeling Pulsatility Index nomograms from different maternal and fetal vessels by quantile regression at 24-40 weeks of gestation: a prospective cross-sectional study

OBJECTIVE

Recent evidences highlight a considerable heterogeneity in the methodology of previously published studies reporting reference ranges for maternal and fetal Dopplers, which may have relevant implications in clinical practice. In view of these limitations, a standardized methodology to construct Doppler charts has been proposed. The aim of this study was to develop charts for pulsatility index (PI) of maternal and fetal Dopplers based upon the recently proposed standardized methodology and using quantile regression.

METHODS

Prospective cross-sectional study including 2516 low-risk singleton pregnancies between 24 and 40 weeks of gestation. The mean uterine, umbilical (UA), middle cerebral (MCA) and their ratio (cerebroplacental ratio, CPR) centile values were established by quantile regression in the considered gestational interval. Interclass correlation coefficient (ICC) of each maternal and fetal vessel was also computed to assess the intra- and inter-observer agreement of the results.

RESULTS

There was a good intra- and inter-observer agreement for each of the explored vessels (ICC >0.92 and >0.91 for a single and two observers, respectively). The 5th, 10th, 50th, 90th and 95th centiles of the reference range for gestation were constructed by quantile regression and compared to previously established reference charts. All the Doppler indices significantly changed with gestation. Second-degree polynomial regression models better described the changes with gestation in PCR and MCA PI values while a linear model better predicted the changes of other Doppler indices with advancing gestation. When compared to other studies reporting reference ranges for maternal and fetal Dopplers, the present charts showed similar median values but different distribution from the median.

CONCLUSIONS

We provided prospective charts of maternal and fetal Dopplers based upon a previously proposed standardized methodology and using quantile regression. When compared to previously published studies, these new charts showed similar median values but different deviations from the median which may help in better differentiating cases at higher risk of placental insufficiency and adverse perinatal outcome.

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.

Cerebroplacental ratio for prediction of adverse intrapartum and neonatal outcomes in a term uncomplicated pregnancy

Background

Fetal hypoxia is one of the major causes of high perinatal morbidity and mortality rates. Doppler ultrasound tests such as cerebroplacental ratio (CPR) evaluation are commonly used to assess blood flow disturbances in placento-umbilical and feto-cerebral circulations. A low cerebroplacental ratio has been shown to be associated with an increased risk of stillbirth regardless of the gestation or fetal weight. We conducted this study to assess the fetal cerebroplacental ratio in prediction of adverse intrapartum and neonatal outcomes in a term, uncomplicated pregnancy to reduce fetal and neonatal morbidity and mortality.

Results

It was found that neonates with CPR ≤1.1 had significantly higher frequencies of cesarean delivery (CS) for intrapartum fetal compromise compared to those with CPR >1.1 (p=0.043). Neonates with CPR ≤1.1 had significantly lower Apgar score at 1 min and 5 min than those with CPR >1.1 (p=0.004) and (p=0.003), respectively. Neonates with CPR ≤1.1 had significantly higher rates of NICU admission than those with CPR <1.1 (p=0.004).

Conclusion

The cerebroplacental ratio shows the highest sensitivity in the prediction of fetal heart rate abnormalities and adverse neonatal outcome in uncomplicated pregnancies at term. The cerebroplacental ratio index is useful in clinical practice in antenatal monitoring of these women in order to select those at high risk of intra- and postpartum complications.

Diagnostic Accuracy of Doppler Ultrasound in Predicting Perinatal Outcome in Appropriate for Gestational Age Fetuses: A Prospective Study

OBJECTIVE

 To elucidate the role of Doppler ultrasound in predicting perinatal outcome in appropriate for gestational age (AGA) fetuses at term.

MATERIAL AND METHODS

 Prospective study carried out in a dedicated research ultrasound clinic. The inclusion criterion was AGA fetuses, defined as those with an estimated fetal weight between the 10th and 90th percentile, at 36 + 0-37 + 6 weeks of gestation. The primary outcome was a composite score of adverse perinatal outcome including either adverse intrapartum events or abnormal acid-base status at birth. Secondary outcomes were the individual components of the primary outcome. The Doppler parameters explored were umbilical artery (UA) PI, middle cerebral artery (MCA) PI, uterine arteries (UtA) PI and cerebroplacental ratio (CPR). Attending clinicians were blinded to Doppler findings. Logistic regression and ROC curve analyses were used to analyze the data.

RESULTS

 553 AGA fetuses were included. There was no difference in mean UA PI (p = 0.486), MCA PI (p = 0.621), CPR (p = 0.832) and UtA PI (p = 0.611) between pregnancies complicated by composite perinatal morbidity compared to those not complicated by composite perinatal morbidity. In pregnancies complicated by adverse intrapartum outcome, the mean MCA PI (1.47 ± 0.4 vs 1.61 ± 0.4, p = 0.0039) was lower compared to the control group, while there was no difference in UA PI (p = 0.758), CPR (p = 0.108), and UtA PI (p = 0.177). Finally, there was no difference in any of the Doppler parameters explored between AGA fetuses with abnormal acid-base status at birth compared to those without abnormal acid-base status at birth. In the logistic regression analysis, UA PI, MCA PI, CPR, UtA PI, EFW and AC percentiles were not independently associated with composite adverse outcome, adverse intrapartum outcome or abnormal acid-base status at birth in non-SGA fetuses. The diagnostic performance of all of these Doppler parameters for predicting composite adverse outcome, adverse intrapartum outcome and abnormal acid-base status was poor.

CONCLUSION

 Cerebroplacental and maternal Doppler is not associated with or predictive of adverse pregnancy outcome in AGA fetuses close to term.

Middle cerebral artery Doppler pulsatility index as a predictor of intrapartum meconium release in prolonged pregnancies

OBJECTIVES

The aim of this study was to asses the correlation of middle cerebral artery pulsatility index (MCA-PI) and perinatal outcomes in prolonged pregnancies.

STUDY DESIGN

This was a prospective study of all consecutive pregnant women beyond 41 weeks' gestation attending for obstetric surveillance during a two years period. We evaluated the predictive value of MCA-PI lower than the 5th percentile (<p5) and the occurrence of: cesarean delivery for fetal distress, 5-min Apgar score <7, arterial cord pH < 7.15, presence of thick meconium at delivery, need for admission to the neonatal intensive care and/or neonatal death.

RESULTS

Three hundred and one pregnancies met the inclusion criteria and were managed expectantly. Of them, 31 (10.3%) fetuses had an MCA-PI < p5, which showed a significant relationship with the presence of thick meconium at birth (p < 0.001), but was not related to any of the other perinatal outcomes.

CONCLUSION

In prolonged pregnancies, the finding of MCA-PI < p5 is related to meconium emission at the time of delivery, but is not associated with an increased risk of adverse perinatal outcome.

The fetal cerebroplacental ratio in pregnancies complicated by hypertensive disorders of pregnancy

BACKGROUND

Hypertensive disorder in pregnancy is common and the optimal ultrasound surveillance of the fetus in this setting is unclear.

AIM

The aim of this study is to assess the relationship between the fetal cerebroplacental ratio (CPR) and perinatal outcomes in pregnancies complicated by maternal hypertension.

MATERIALS AND METHODS

A retrospective cohort study was performed over ten years at a single centre. All women who had an ultrasound scan between 34 and 37 weeks gestation with a non-anomalous singleton pregnancy were included. The hypertensive cohorts were compared to a non-hypertensive cohort. Each cohort was divided into low CPR for gestational age, or normal/high CPR and these were correlated with intrapartum and perinatal outcomes.

RESULTS

A low CPR in a hypertensive pregnancy is associated with an increased risk of induction of labour, emergency caesarean section and poor perinatal outcome. This significance persists when adjusted for gestational age and birth weight. The diagnosis of pre-eclampsia combined with a low CPR markedly increases the risk of poor perinatal outcome, with 52.6% (P < 0.001) of fetuses in this group having either neonatal intensive care unit admission, respiratory distress, low Apgar score, or acidosis. The odds ratio of a fetus with low CPR in a woman with pre-eclampsia having a poor composite outcome is 4.09 (95% CI: 1.85-9.06).

CONCLUSION

There is an association between low CPR and the perinatal outcomes of pregnancies complicated by a hypertensive disorder. This association appears to be stronger in pregnancies complicated by pre-eclampsia than in other types of hypertensive disorders.

Comparing the cerebro-placental to umbilico-cerebral Doppler ratios for the prediction of adverse neonatal outcomes in pregnancies complicated by fetal growth restriction

OBJECTIVE

The cerebroplacental ratio (CPR) has shown utility as a surrogate marker for fetal growth restriction and can be used to stratify the risk for adverse perinatal outcomes in affected pregnancies. However, recent studies suggest that its inverse, the umbilico-cerebral ratio (UCR), may be a better predictor of such outcomes. The aim of this study was to compare the prognostic accuracy of CPR to that of UCR Doppler in predicting short-term adverse perinatal outcomes in growth-restricted fetuses.

METHODS

We conducted a secondary analysis using data from a prospective study on women referred for fetal growth ultrasounds between 26 and 36 weeks of gestation and with an EFW < 10th percentile by Hadlock standard. The CPR and UCR were converted into Z-scores adjusted for gestational age at ultrasound. Abnormal CPR was defined as Z-score below the 10th percentile for the gestational age and abnormal UCR as Z-score above the 90th percentile. We calculated sensitivity and specificity of the two Doppler parameters for predicting composite adverse perinatal outcome (APO) defined as the presence of any one of the following: umbilical cord arterial pH <7.10, Apgars at 5 min <7, NICU admission,grade III/IV intraventricular hemorrhage (IVH), neonatal seizure and death. Logistic regression analysis was performed, ROC curves plotted and the area under the ROC curve (AUC) were compared between CPR and UCR.

RESULTS

Over the study period, there were 197 women meeting inclusion criteria, of which 27 (13.7%) had a composite adverse neonatal outcome. The sensitivity using CPR Z-score for predicting the composite APO was higher thanwas similar to using UCR Z-score (39.3% compared with 37%) for a similar specificity (94.7 versus 94.1), respectively. However, the positive predictive value (PPV) was higher for CPR (55% vs UCR 50%) and the negative predictive values (NPV) were similar. For a fixed false positive rate of 10%, the detection rates for adverse neonatal outcomes were 40% using either CPR or UCR. The AUC for CPR and UCR were 0.70 and 0.68, respectively.

CONCLUSION

This study did not find any advantage in utilizing the UCR over the CPR.

Universal late pregnancy ultrasound screening to predict adverse outcomes in nulliparous women: a systematic review and cost-effectiveness analysis

BACKGROUND

Currently, pregnant women are screened using ultrasound to perform gestational aging, typically at around 12 weeks' gestation, and around the middle of pregnancy. Ultrasound scans thereafter are performed for clinical indications only.

OBJECTIVES

We sought to assess the case for offering universal late pregnancy ultrasound to all nulliparous women in the UK. The main questions addressed were the diagnostic effectiveness of universal late pregnancy ultrasound to predict adverse outcomes and the cost-effectiveness of either implementing universal ultrasound or conducting further research in this area.

DESIGN

We performed diagnostic test accuracy reviews of five ultrasonic measurements in late pregnancy. We conducted cost-effectiveness and value-of-information analyses of screening for fetal presentation, screening for small for gestational age fetuses and screening for large for gestational age fetuses. Finally, we conducted a survey and a focus group to determine the willingness of women to participate in a future randomised controlled trial.

DATA SOURCES

We searched MEDLINE, EMBASE and the Cochrane Library from inception to June 2019.

REVIEW METHODS

The protocol for the review was designed a priori and registered. Eligible studies were identified using keywords, with no restrictions for language or location. The risk of bias in studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Health economic modelling employed a decision tree analysed via Monte Carlo simulation. Health outcomes were from the fetal perspective and presented as quality-adjusted life-years. Costs were from the perspective of the public sector, defined as NHS England, and the costs of special educational needs. All costs and quality-adjusted life-years were discounted by 3.5% per annum and the reference case time horizon was 20 years.

RESULTS

Umbilical artery Doppler flow velocimetry, cerebroplacental ratio, severe oligohydramnios and borderline oligohydramnios were all either non-predictive or weakly predictive of the risk of neonatal morbidity (summary positive likelihood ratios between 1 and 2) and were all weakly predictive of the risk of delivering a small for gestational age infant (summary positive likelihood ratios between 2 and 4). Suspicion of fetal macrosomia is strongly predictive of the risk of delivering a large infant, but it is only weakly, albeit statistically significantly, predictive of the risk of shoulder dystocia. Very few studies blinded the result of the ultrasound scan and most studies were rated as being at a high risk of bias as a result of treatment paradox, ascertainment bias or iatrogenic harm. Health economic analysis indicated that universal ultrasound for fetal presentation only may be both clinically and economically justified on the basis of existing evidence. Universal ultrasound including fetal biometry was of borderline cost-effectiveness and was sensitive to assumptions. Value-of-information analysis indicated that the parameter that had the largest impact on decision uncertainty was the net difference in cost between an induced delivery and expectant management.

LIMITATIONS

The primary literature on the diagnostic effectiveness of ultrasound in late pregnancy is weak. Value-of-information analysis may have underestimated the uncertainty in the literature as it was focused on the internal validity of parameters, which is quantified, whereas the greatest uncertainty may be in the external validity to the research question, which is unquantified.

CONCLUSIONS

Universal screening for presentation at term may be justified on the basis of current knowledge. The current literature does not support universal ultrasonic screening for fetal growth disorders.

FUTURE WORK

We describe proof-of-principle randomised controlled trials that could better inform the case for screening using ultrasound in late pregnancy.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42017064093.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 15. See the NIHR Journals Library website for further project information.

The role of abnormal cerebroplacental ratio in predicting adverse fetal outcome in pregnancies with scheduled induction of labor

OBJECTIVE

To investigate the role of abnormal cerebroplacental ratio (CPR) in predicting adverse fetal outcome in pregnancies with induction of labor.

METHODS

This prospective observational study conducted at Medeniyet University Göztepe Training and Research Hospital between December 1, 2018 and October 31, 2019 enrolled women with scheduled induction of labor at or beyond 37 weeks of pregnancy. Women with singleton non-anomalous fetuses with cephalic presentation and who had Bishop scores of 5 or less in pelvic examination were included in the study. Exclusion criteria were the presence of uterine scar history, non-cephalic presentation, multiple pregnancy, vacuum- or forceps-assisted delivery, and shoulder dystocia. Using fetal Doppler ultrasound, CPR was calculated (the ratio of umbilical artery to middle cerebral artery pulsatility index) and categorized into abnormal CPR (<1) and normal CPR (≥1). Data on maternal and delivery characteristics, fetal birth weight, and fetal complications were compared between the groups.

RESULTS

A total of 145 women were included, 28 in the abnormal CPR group and 117 in the normal CPR group. Multivariate analysis revealed labor induction at a later week of pregnancy (odds ratio [OR] 10.33, P = 0.001), lack of intrauterine growth restriction (IUGR) (OR 13.21, P = 0.001), fetal distress (OR 8.14, P = 0.003) or meconium aspiration (OR 159.91, P = 0.001), and umbilical artery pH values greater than 7.31 (OR 17.51, P = 0.015) to be associated with an increased likelihood of having normal (≥1) CPR values. Receiver operating characteristic analysis revealed association of normal CPR values with later labor induction (cut-off value of >38.3 weeks, P = 0.001), higher birth weight (cut-off value of >2460 g, P = 0.022) and higher umbilical artery pH (cut-off value of >7.31, P = 0.007).

CONCLUSION

Our findings revealed the significant role of abnormal CPR in predicting adverse fetal outcome in singleton pregnancies with scheduled induction of labor.

Shipp TD, Zelop CM, Maturen KE, Deshmukh SP, Dudiak KM, Henrichsen TL, Oliver ER, Poder L, Sadowski EA, Simpson L, Weber TM, Winter T, Glanc P. ACR Appropriateness Criteria® Growth Disturbances-Risk of Fetal Growth Restriction

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

Sex-specific reference ranges of cerebroplacental and umbilicocerebral ratios: longitudinal study

OBJECTIVES

Observational studies have shown that low cerebroplacental ratio (CPR) values predict an increased risk of adverse perinatal outcome. The inverse ratio, i.e. the umbilicocerebral ratio (UCR), has been suggested to be a better predictor as it rises with increasing degree of fetal compromise. However, longitudinal reference ranges for UCR have not been established, and whether gestational-age-dependent changes in CPR or UCR differ between male and female fetuses has not been studied. Thus, the aims of this study were to investigate sex-specific, gestational-age-associated serial changes in CPR and UCR during the second half of pregnancy and to establish longitudinal reference ranges.

METHODS

This was a secondary analysis of prospectively collected data from a dual-center longitudinal observational cohort study of low-risk singleton pregnancies. Doppler blood-flow velocity waveforms were obtained serially from the umbilical artery (UA) and fetal middle cerebral artery (MCA) from 19-41 weeks' gestation, and pulsatility indices (PIs) were determined. CPR and UCR were calculated as the ratios MCA-PI/UA-PI and UA-PI/MCA-PI, respectively. The course and outcome of pregnancies were recorded, and the sex of the fetus was determined after delivery. Reference intervals for CPR and UCR were constructed using multilevel modeling, and gestational-age-specific Z-scores in male and female fetuses were compared.

RESULTS

Of a total of 299 pregnancies enrolled, 284 (148 male and 136 female fetuses) were included in the final analysis, and 979 paired measurements of UA-PI and MCA-PI were used to construct sex-specific longitudinal reference intervals. The relationship of both CPR and UCR with gestational age was U-shaped, but in opposite directions. There was a small but significant difference in Z-scores of CPR and UCR between male and female fetuses throughout the second half of pregnancy (P = 0.007).

CONCLUSIONS

We have established longitudinal reference ranges for CPR and UCR suitable for serial monitoring, with the possibility of refining assessment by using fetal sex-specific ranges and conditioning by a previous measurement. The clinical significance of such refinements needs further evaluation. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Prescriptive Reference Standards of Third-Trimester Cerebroplacental Ratio and Its Physiological Determinants

OBJECTIVE

To construct valid reference standards reflecting optimal cerebroplacental ratio and to explore its physiological determinants.

METHODS

A cohort of 391 low-risk pregnancies of singleton pregnancies of nonmalformed fetuses without maternal medical conditions and with normal perinatal outcomes was created. Doppler measurements of the middle cerebral artery and umbilical artery were performed at 24-42 weeks. Reference standards were produced, and the influence of physiological determinants was explored by nonparametric quantile regression. The derived standards were validated in a cohort of 200 low-risk pregnancies.

RESULTS

Maternal body mass index was significantly associated with the 5th centile of the cerebroplacental ratio. For each additional unit of body mass index, the 5th centile was on average 0.014 lower. The derived 5th, 10th, and 50th centiles selected in the validation cohort were 5, 9.5, and 51% of the measurements.

CONCLUSIONS

This study provides methodologically sound prescriptive standards and suggests that maternal body mass index is a determinant of a cutoff commonly used for decision-making.

Cerebroplacental ratio in predicting adverse perinatal outcome: a meta-analysis of individual participant data

Objective

To investigate if cerebroplacental ratio (CPR) adds to the predictive value of umbilical artery pulsatility index (UA PI) alone – standard of practice – for adverse perinatal outcome in singleton pregnancies.

Design and setting

Meta‐analysis based on individual participant data (IPD).

Population or sample

Ten centres provided 17 data sets for 21 661 participants, 18 731 of which could be included. Sample sizes per data set ranged from 207 to 9215 individuals. Patient populations varied from uncomplicated to complicated pregnancies.

Methods

In a collaborative, pooled analysis, we compared the prognostic value of combining CPR with UA PI, versus UA PI only and CPR only, with a one‐stage IPD approach. After multiple imputation of missing values, we used multilevel multivariable logistic regression to develop prediction models. We evaluated the classification performance of all models with receiver operating characteristics analysis. We performed subgroup analyses according to gestational age, birthweight centile and estimated fetal weight centile.

Main outcome measures

Composite adverse perinatal outcome, defined as perinatal death, caesarean section for fetal distress or neonatal unit admission.

Results

Adverse outcomes occurred in 3423 (18%) participants. The model with UA PI alone resulted in an area under the curve (AUC) of 0.775 (95% CI 0.709–0.828) and with CPR alone in an AUC of 0.778 (95% CI 0.715–0.831). Addition of CPR to the UA PI model resulted in an increase in the AUC of 0.003 points (0.778, 95% CI 0.714–0.831). These results were consistent across all subgroups.

Conclusions

Cerebroplacental ratio added no predictive value for adverse perinatal outcome beyond UA PI, when assessing singleton pregnancies, irrespective of gestational age or fetal size.

Tweetable abstract

Doppler measurement of cerebroplacental ratio in clinical practice has limited added predictive value to umbilical artery alone.

Doppler measurement of cerebroplacental ratio in clinical practice has limited added predictive value to umbilical artery alone.

Sleep in the Supine Position during Pregnancy Is Associated with Fetal Cerebral Redistribution

The supine sleep position in late pregnancy is a major risk factor for stillbirth, with a population attributable risk of 5.8% and one in four pregnant women reportedly sleeping in a supine position. Although the mechanisms linking the supine sleep position and late stillbirth remain unclear, there is evidence that it exacerbates pre-existing maternal sleep disordered breathing, which is another known risk factor for adverse perinatal outcomes. Given that maternal sleep position is a potentially modifiable risk factor, the aim of this study was to characterize and correlate uteroplacental and fetal hemodynamics, including cardiac function, in a cohort of women with apparently uncomplicated pregnancies with their nocturnal sleep position. This was a prospective observational cohort study at an Australian tertiary obstetric hospital. Women were asked to complete a series of questions related to their sleep position in late pregnancy after 35 weeks of completed gestation. They also underwent an ultrasound assessment where Doppler indices of various fetoplacental vessels and fetal cardiac function were measured. Regional cerebral perfusion was also assessed. Pregnancy outcome data was extracted from the electronic hospital database for analysis. A total of 274 women were included in the final analysis. Of these, 78.1% (214/274) reported no supine sleep, and 21.9% (60/274) reported going to sleep in a supine position. The middle cerebral artery, anterior cerebral artery, and vertebral artery pulsatility indices were all significantly lower in the supine sleep cohort, as was the cerebroplacental ratio. There were no significant differences in the mode or indication for delivery or in serious neonatal outcomes, including 5-min Apgar score < 7, acidosis, and neonatal intensive care unit admission between cohorts. Women in the supine cohort were more likely to have an infant with a BW > 90th centile (p = 0.04). This data demonstrates fetal brain sparing in association with the maternal supine sleep position in a low-risk population. This data contributes to the growing body of literature attempting to elucidate the etiological pathways responsible for the association of late stillbirth with the maternal supine sleep position.

Cerebroplacental ratio (CPR) and reduced fetal movement: predicting neonatal outcomes

Objective: The aim of this study was to evaluate the role of cerebroplacental ratio (CPR) in term pregnancies with reduced fetal movements (RFM) and appropriate for gestational age (AGA)fetuses to predict poor neonatal outcomes.Methods: A prospective cohort study was performed on 150 singleton pregnancies with gestational age of 37-41 weeks and multiple episodes of RFM (case group) and 150 pregnancies within the same criteria only without RFM (control group). Both groups had appropriate for gestational age (AGA)fetuses. Umbilical artery (UA) and middle cerebral artery (MCA) pulsatility indices (PI) were measured, and MCA to UA ratio (CPR) was calculated. Doppler indices and neonatal outcomes were compared between the two groups. Independent prediction role of CPR MoM was evaluated through a binary logistic regression method.Results: The RFM group had significantly higher UA- PI MoM (1.01 ± 0.19 versus 0.86 ± 0.05, p < .001), lower MCA MoM (1.28 ± 0.20 versus 1.40 ± 0.13, (p < .001)) and lower CPR MoM (0.98 ± 0.24 versus 1.23 ± 0.12, (p < .001)) compared to the control group. Mean umbilical artery pH was lower in the RFM group and the frequency of neonatal UA cord pH <7.2 was higher in the RFM group. In RFM group, CPR MoM showed a significant linear correlation with birth weight centiles (r = 0.244, p = .003), umbilical artery pH (r = 0.319, p < .001) and Apgar score at minute 1 (r = 0.332, p < .001). CPR MoM exhibited negative correlation with duration of NICU stay (r= -0.187, p = .022). No similar correlation was observed in the control group. In binary logistic regression analysis, CPR MoM was adjusted for the results of NST; and it was concluded that CPR MoM was the only significant predictor of Apgar score minute 1 = <7 (OR: 0.004; 95% CI: 0.0002-0.0673, p < .001), umbilical artery ph <7.2 (OR: 0.019; 95% CI: 0.00005-0.0423, p < .001) and NICU admission (OR: 0.116; 95% CI: 0.018-0.744, p = .023). In multivariate binary logistic regression analysis included parity, history of abortion and ART, AFI, BPP and CPR MoM; the AFI (OR: 0.976; 95% CI: 0.957-0.995, p = .014), BPP (OR: 0.306; 95% CI: 0.172-0.545, p < .001) and CPR MoM (OR: 0.00005 95% CI: 0.000003-0.00061, p < .001) were the significant predictor of RFM. Area under the curve in receiver operating characteristics (ROC) curve was calculated as 0.828 for CPR MoM as a predictor of RFM (SE: 0.024, p < .001), yielding sensitivity and specificity estimates of 80.0% and 65.0%, respectively, using an optimal cutoff level of = < 1.19.Conclusion: This study concluded that reduced fetal movement was significantly related to low CPR MOM. Also, it showed the independent role of CPR MoM for prediction of lower neonatal umbilical artery pH, lower Apgar score minute 1 and higher rate of NICU admission in AGA term fetuses without considering NST results. Also, AFI, BPP and CPR MoM are significant predictors of RFM.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Feto-placental Dopplers are not altered in women with obstructive sleep apnoea symptoms

BACKGROUND

Snoring, gasping or choking during sleep are common symptoms of sleep-disordered breathing and are associated with multiple adverse maternal and obstetric outcomes. The mechanisms responsible remain unknown; however, placental dysfunction is suspected.

AIMS

The aim of this study was to investigate feto-placental and fetal cardiac function in women with pregnancies complicated by obstructive sleep apnoea symptoms.

MATERIALS AND METHODS

This was a prospective observational cohort study at a large tertiary obstetric hospital in Australia. Women were asked to complete a questionnaire relating to the presence and severity of obstructive sleep apnoea symptoms. They also underwent an ultrasound scan where Doppler indices of various feto-placental vessels and fetal cardiac function were measured. Regional cerebral perfusion was also assessed.

RESULTS

A total of 255 women were included in the final analysis. Of these, 36.1% (92/255) of women reported no obstructive sleep apnoea symptoms; 63.9% (163/255) reported they experienced some form of obstructive sleep apnoea symptoms that included any frequency of snoring or choking/gasping, while 42.0% (107/255) complained of severe obstructive sleep apnoea symptoms (snoring ≥ 3 times a week or choking/gasping). There were no significant differences in feto-placental Dopplers or fetal cardiac function parameters in women with obstructive sleep apnoea symptoms. There were also no differences in regional cerebral blood flow between groups, or any correlation with severity of symptoms.

CONCLUSIONS

Our data challenge the current perspective that adverse perinatal outcomes in women with obstructive sleep apnoea symptoms are related primarily to placental dysfunction and fetal compromise.

Bioethics of Translating Limited Evidence into Clinical Practice: Case Study of the Cerebroplacental Ratio

Bioethics can help address the challenges of translating research into clinical practice in the twenty-first century. The cerebroplacental ratio in obstetrical ultrasound provides a case study of how bioethical principles can help advance practical approaches when evidence is limited. This can help clinicians use cerebroplacental ratio when additional risk factors are present in critical cases that warrant increased surveillance; disclose limited information appropriately; allocate resources; and weigh benefits against risks. Balancing the key ethical principles of respect for autonomy, beneficence, non-maleficence, and justice within this context illuminates how bioethics can assist health care providers as well as help set a research agenda. Such analyses are essential to improving clinical care, given the rapid pace at which medicine is evolving.

A Radiologist's Guide to the Performance and Interpretation of Obstetric Doppler US

Doppler US provides a unique window to the fetoplacental circulation, allowing assessment of fetal well-being. Doppler US of the umbilical artery is an integral component of managing the fetus with growth restriction; and Doppler US of the middle cerebral artery, as a noninvasive means of detecting fetal anemia, has revolutionized the management of pregnancies complicated by alloimmunization. Serial use of amniocentesis, with its attendant risks, has been replaced by serial Doppler US examinations. Invasive procedures are now reserved for the treatment of anemia with intrauterine transfusion. Technique is critical to obtain the best waveforms for ease of shape assessment, velocity measurement, and calculation of various ratios. In this article, the safety of Doppler US is reviewed, the fetal circulation is described, and the role of Doppler US is demonstrated in first-trimester screening and in the evaluation of growth restriction, anemia, and other causes of fetal compromise in the second and third trimesters. Sampling technique is explained, and normal and abnormal waveforms are illustrated for the ductus venosus, umbilical artery, umbilical vein, middle cerebral artery, and uterine artery. Some examples of clinical cases are provided to illustrate how the results are used in clinical practice. Clinical examples of velamentous insertion and vasa previa are also provided to aid the practicing radiologist with recognition of these entities. In particular, vasa previa is considered a critical finding; it alters pregnancy management, requiring hospital admission, administration of steroid therapy, and planned early cesarean delivery. ^©RSNA, 2019.

Maternal sleep disordered breathing assessed by Epworth Sleepiness Scale and abnormal feto-placental Dopplers

Objective: Excessive daytime sleepiness is a frequently described phenomenon in pregnant women. The Epworth Sleepiness Scale (ESS) is a self reported standardized method of assessing sleep propensity and has been used extensively within pregnant populations. An elevated score is associated with sleep disordered breathing, as well as adverse obstetric and neonatal outcomes which may be indicative of a degree of placental dysfunction. Thus the aim of this study was to prospectively assess women using the Epworth questionnaire in conjunction with an ultrasound in both the second and third trimesters to determine if there was a difference in ESS scores across gestation and if a mid or late gestation assessment was correlated with Doppler ultrasound measures of fetal well-being.Materials and methods: Participants were prospectively recruited from a tertiary obstetric hospital and completed both an Epworth questionnaire and ultrasound examination in the second and third trimesters.Results: A total of 302 women took part in this cohort study. There was a statistically significant (p = .02) increase in ESS score across gestation. There was however no correlation identified in either the second or third trimester between ESS score and umbilical artery pulsatility index, middle cerebral artery pulsatility index, cerebroplacental ratio, umbilical venous flow, uterine artery pulsatility index or estimated fetal weight. A higher birth weight is associated with a higher ESS score in the second trimester but not in the third trimester (p = .03).Conclusions: Maternal sleep disordered breathing assessed by the ESS score is only correlated with increased birth weight but not with fetal Doppler parameters in low risk pregnancies.

The value of fetal Doppler indices as predictors of perinatal outcome in women with preeclampsia with severe features

Objective: To evaluate the diagnostic performance of Doppler sonography of umbilical artery (UA), fetal middle cerebral artery (MCA), ductus venosus (DV) & umbilical vein (UV) for prediction of adverse perinatal outcome.Material and Methods: A prospective cohort study conducted on 60 women diagnosed  with preeclampsia with severe features divided into two groups based on adverse perinatal outcome.Results: Statistically Significant differences were demonstrated UA PI (1.28 ± 0.23 vs. 0.96 ± 0.21, P <0.001), UA RI (0.78 ± 0.09 vs. 0.62 ± 0.09, P <0.001), MCA PI (1.27 ± 0.28 vs. 1.45±0.20, P 0.005), MCA RI (0.67 ± 0.10 vs. 0.76 ± 0.08, P<0.001), Cerebroplacental ratio (1.01 ± 0.36 vs. 1.57 ± 0.35, P <0.001), DV PVIV (0.67 ± 0.20 vs. 0.51 ± 0.14, P= 0.004), DV PSV (54.74 ± 17.11 vs. 42.15 ± 9.42, P= 0.004)  and abnormal DV a wave (23.8 vs. 0%, P = 0.004) in women with adverse and normal perinatal outcome respectively. UA PI and CPR had the highest specificity while UA RI had the highest sensitivity for detection of adverse perinatal outcome.Conclusion: CPR < 1 can be used to identify fetuses at risk of morbidity and mortality among such cases.

Impact of low-dose aspirin on adverse perinatal outcome: meta-analysis and meta-regression

OBJECTIVE

To perform a meta-analysis and meta-regression of randomized controlled trials (RCTs) to evaluate the impact of low-dose aspirin (LDA) on perinatal outcome, independent of its effect on pre-eclampsia (PE), preterm birth and low birth weight.

METHODS

An electronic search of EMBASE, PubMed, CENTRAL, PROSPERO and Google Scholar databases was performed to identify RCTs assessing the impact of LDA in pregnancy, published in English prior to May 2019, which reported perinatal outcomes of interest (placental abruption, delivery mode, low 5-min Apgar score, neonatal acidosis, neonatal intensive care unit admission, periventricular hemorrhage and perinatal death). Risk ratios (RR) and 95% CI were calculated and pooled for analysis. Analysis was stratified according to gestational age at commencement of treatment (≤ 16 weeks vs > 16 weeks) and subgroup analysis was performed to assess the impact of aspirin dose (< 100 mg vs ≥ 100 mg). Meta-regression was used to assess the impact of LDA on perinatal outcome, independent of the reduction in PE, preterm birth and low birth weight.

RESULTS

Forty studies involving 34 807 participants were included. When LDA was commenced ≤ 16 weeks' gestation, it was associated with a significant reduction in the risk of perinatal death (RR, 0.47; 95% CI, 0.25-0.88; P = 0.02; number needed to treat, 92); however, this risk reduction was only seen when a daily dose of ≥ 100 mg was administered. If commenced > 16 weeks' gestation, LDA was associated with a significant reduction in 5-min Apgar score < 7 (RR, 0.75; 95% CI, 0.58-0.96; P = 0.02) and periventricular hemorrhage (RR, 0.68; 95% CI, 0.47-0.99; P = 0.04), but a trend towards an increase in the risk of placental abruption (RR, 1.20; 95% CI, 1.00-1.46; P = 0.06) was also noted. LDA was not associated with any significant increase in adverse events if commenced ≤ 16 weeks gestation. LDA had no effect on delivery mode, irrespective of the gestational age at which it was started. Meta-regression confirmed that the effect of LDA on perinatal death, when treatment was started ≤ 16 weeks' gestation, was independent of any reduction in the rate of PE and preterm birth.

CONCLUSION

LDA improves some important perinatal outcomes, without increasing adverse events such as placental abruption or periventricular hemorrhage, and its utility, if commenced prior to 16 weeks' gestation, may be considered in a wider context beyond the prevention of PE or fetal growth restriction. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Diagnostic accuracy of Doppler ultrasound in predicting perinatal outcome in pregnancies at term: A prospective longitudinal study

INTRODUCTION

To explore the strength of association and the diagnostic accuracy of umbilical (UA), middle cerebral (MCA), uterine arteries pulsatility index (PI) and the cerebroplacental ratio in predicting an adverse outcome when applied to singleton pregnancies at term.

MATERIAL AND METHODS

Prospective study carried out in a dedicated research ultrasound clinic. Attended clinicians were blinded to Doppler findings. Inclusion criteria were consecutive singleton pregnancies between 36+0 and 37+6  weeks of gestation. The primary outcome was a composite score of adverse perinatal outcome. Logistic regression and ROC curve analyses were used to analyze the data.

RESULTS

In all, 600 consecutive singleton pregnancies from 36 weeks of gestation were included in the study. Mean MCA PI (1.1 ± 0.2 vs 1.5 ± 0.4, P < 0.001) and cerebroplacental ratio (1.4 ± 0.4 vs 1.9 ± 0.6, P < 0.001) were lower, whereas uterine arteries PI (0.8 ±0.2 vs 0.7 ±0.3, P = 0.001) was higher in pregnancies experiencing than in those not experiencing composite adverse outcome. Conversely, there was no difference in either UA PI (P = 0.399) or estimated fetal weight centile (P = 0.712) between the two groups, but AC centile was lower in fetuses experiencing composite adverse outcome (45.4 vs 53.2, P = 0.040). At logistic regression analysis, MCA PI (odds ratio [OR] 0.1, 95% CI 0.01-.2, P = 0.001), uterine arteries PI (OR 1.4, 95% CI 1.2-1.6, P = 0.001), abdominal circumference centile (OR 1.12, 95% CI 1.1-1.4, P = 0.001) and gestational age at birth (OR 1.6, 95% CI 1.2-2.1, P = 0.004) were independently associated with composite adverse outcome. Despite this, the diagnostic accuracy of Doppler in predicting adverse pregnancy outcome at term was poor.

CONCLUSIONS

MCA PI and cerebroplacental ratio are associated with adverse perinatal outcome at term. However, their predictive accuracy for perinatal compromise is poor, and thus their use as standalone screening test for adverse perinatal outcome in singleton pregnancies at term is not supported.

Association between the fetal cerebroplacental ratio and biomarkers of hypoxia and angiogenesis in the maternal circulation at term

OBJECTIVES

A low fetal cerebroplacental ratio (CPR) in late pregnancy is a marker of a fetus that has failed to reach its growth potential and is associated with a variety of perinatal and pregnancy complications. It is not known if it is also correlated with aberrations in angiogenic, hypoxia-responsive or inflammatory cytokine levels in the maternal circulation. We investigated if there were any differences in levels of biomarkers of angiogenesis, endothelial cell dysfunction, hypoxia and/or inflammation in term pregnancies with a low fetal CPR compared to controls. We hypothesized that as the CPR is a marker of suboptimal growth, this would be reflected in a shift towards upregulation of hypoxia-responsive factors even in non-small for gestational age fetuses.

STUDY DESIGN

We used Multiplex ELISA to measure a panel of 28 candidate biomarkers of angiogenesis and/or hypoxia in pre-labour maternal plasma from 113 women at term, stratified for CPR <10th centile vs. CPR >10th centile. Plasma levels of the biomarkers were measured using 2 multiplex Luminex assays - a commercially available human angiogenesis/growth factor panel (R&D Systems®), comprising 15 analytes and an in-house custom panel of a further 13 candidate biomarkers.

RESULTS

Of the 28 candidate biomarkers investigated, we found significantly elevated levels of Carbonic Anhydrase 9 and soluble Fms-like tyrosine kinase (Vascular Endothelial Growth Factor Receptor 1), and lower levels of Placental Growth Factor in plasma from women with a low fetal CPR. The soluble Fms-like tyrosine kinase-1/Placental Growth Factor ratio was also markedly elevated in this cohort. We also demonstrated significant inverse correlations between the fetal CPR and Carbonic Anydrase 9, soluble Fms-like tyrosine kinase and Hepatocyte Growth Factor.

CONCLUSIONS

A low fetal CPR is associated with changes in some hypoxia-responsive and angiogenesis factors in the maternal circulation in pregnancies with normally grown fetuses.