Utility of the cerebro-placental-uterine ratio in predicting composite adverse perinatal outcomes in pregestational diabetes: A prospective cohort study.

PURPOSE: To examine the cerebro-placental-uterine ratio (CPUR) in pregnant women with pregestational diabetes and determine its role in predicting adverse prenatal outcomes. METHODS: This prospective, cohort study conducted at a tertiary hospital included 65 patients with pregestational diabetes (25 with type1 diabetes, 40 with type2 diabetes) and 130 low-risk patients in the control group. The cerebroplacental (CPR) ratio and the CPUR were calculated. Composite adverse perinatal outcome (CAPO) is defined as the presence of any of the following: (1) Neonatal intensive care unit (NICU) admission, (2) Apgar at 5 min <7, and (3) umbilical cord arterial pH <7.10. The relationship of CPR and CPUR with CAPO was investigated. RESULTS: CPR and CPUR were significantly lower in the pregestational diabetes group than in the control group. The NICU admission was higher in the case group. In receiver operating characteristic analyses, the optimal cut-off value of CPUR was 1.46 (AUC = 0.72, p = 0.003, 80% sensitivity, and 69% specificity) to predict CAPO and the optimal cut-off value of CPUR was 1.50 for NICU admission (AUC = 0.70, p = 0.013, 77% sensitivity, and 66% specificity). CONCLUSION: Low CPUR values were found to be associated with adverse perinatal outcomes in women with pregestational diabetes. With the increasing number of studies, CPUR is expected to be utilized more widely in routine obstetric practice.

Longitudinal change in cerebro-placental ratio (CPR) between 37 and 40 weeks of pregnancy is associated with non-reassuring fetal status and increased risk of cesarean section.

OBJECTIVE: To evaluate in low-risk pregnancies if longitudinal change in cerebro-placental ratio (CPR) between 37 and 40 weeks of pregnancy is associated with cesarean section (CS) for non-reassuring fetal status (NRFS) during labor. METHODS: This is a prospective observational study of women with singleton low-risk pregnancies who underwent an ultrasound scan at 36 + 0 to 37 + 6 and 39 + 0 to 41 + 6 weeks of pregnancy, when the CPR was calculated from the middle cerebral artery (MCA) and umbilical artery (UA) pulsatility indices. Managing professionals were kept blinded to the Doppler results. The association of the longitudinal change between both CPR (z-velocity) to CS for NRFS was evaluated by logistic regression. RESULTS: A total of 401 pregnancies were included. The mean time interval between both CPR evaluations was 21 days (SD 7). A CS for fetal distress was performed in 7% of pregnancies. Independent of the CPR at 37 weeks, the likelihood of CS for fetal distress was significantly decreased by the longitudinal changes from 37 to 40 weeks (OR 0.61, 95%CI 0.4-0.92; p=.018). This association remained significant after further adjustment for potential confounders (nulliparity, maternal weight at booking and estimated fetal weight at 37): (OR 0.64, 95%CI 0.41-0.98; p=.044). CONCLUSIONS: The longitudinal change of CPR between 37 and 40 weeks is associated with the need for CS for NRFS during labor.

Reduced fetal growth velocity and weight loss are associated with adverse perinatal outcome in fetuses at risk of growth restriction.

BACKGROUND: Although fetal size is associated with adverse perinatal outcome, the relationship between fetal growth velocity and adverse perinatal outcome is unclear. OBJECTIVE: This study aimed to evaluate the relationship between fetal growth velocity and signs of cerebral blood flow redistribution, and their association with birthweight and adverse perinatal outcome. STUDY DESIGN: This study was a secondary analysis of the TRUFFLE-2 multicenter observational prospective feasibility study of fetuses at risk of fetal growth restriction between 32+0 and 36+6 weeks of gestation (n=856), evaluated by ultrasound biometry and umbilical and middle cerebral artery Doppler. Individual fetal growth velocity was calculated from the difference of birthweight and estimated fetal weight at 3, 2, and 1 week before delivery, and by linear regression of all available estimated fetal weight measurements. Fetal estimated weight and birthweight were expressed as absolute value and as multiple of the median for statistical calculation. The coefficients of the individual linear regression of estimated fetal weight measurements (growth velocity; g/wk) were plotted against the last umbilical-cerebral ratio with subclassification for perinatal outcome. The association of these measurements with adverse perinatal outcome was assessed. The adverse perinatal outcome was a composite of abnormal condition at birth or major neonatal morbidity. RESULTS: Adverse perinatal outcome was more frequent among fetuses whose antenatal growth was <100 g/wk, irrespective of signs of cerebral blood flow redistribution. Infants with birthweight <0.65 multiple of the median were enrolled earlier, had the lowest fetal growth velocity, higher umbilical-cerebral ratio, and were more likely to have adverse perinatal outcome. A decreasing fetal growth velocity was observed in 163 (19%) women in whom the estimated fetal weight multiple of the median regression coefficient was <-0.025, and who had higher umbilical-cerebral ratio values and more frequent adverse perinatal outcome; 67 (41%; 8% of total group) of these women had negative growth velocity. Estimated fetal weight and umbilical-cerebral ratio at admission and fetal growth velocity combined by logistic regression had a higher association with adverse perinatal outcome than any of those parameters separately (relative risk, 3.3; 95% confidence interval, 2.3-4.8). CONCLUSION: In fetuses at risk of late preterm fetal growth restriction, reduced growth velocity is associated with an increased risk of adverse perinatal outcome, irrespective of signs of cerebral blood flow redistribution. Some fetuses showed negative growth velocity, suggesting catabolic metabolism.

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

INTRODUCTION: This study aimed to evaluate the association of the Myocardial Performance Index (MPI) and Cerebro-Placental Ratio (CPR) in predicting adverse perinatal outcomes in fetuses who are appropriately-grown (AGA), small-for-gestational-age (SGA) and growth restricted (FGR). METHODS: Singleton pregnancies were recruited after 24 weeks. The patients were recruited after having been classified as AGA (AC/EFW > 10th centile), SGA (AC/EFW-3rd-10th centile without doppler abnormalities), and FGR (AC/EFW < 3rd centile or 3rd-10th centile with doppler abnormalities). A total of 103 cases comprising 48 AGA, 11 SGA, and 44 FGRfetuses were recruited. The Pulsatility Index of the Umbilical artery, Middle cerebral artery, Ductus Venosus, and Aortic Isthmus was obtained. MPI and CPR were calculated too. The primary outcome was to evaluate the predictive value of MPI and CPR for the composite adverse perinatal outcome. RESULTS: The mean gestational age of recruitment was 30 weeks. The OR for Composite Adverse Perinatal Outcome in FGR group for MPI > .47 and CPR < 1.67 was 3.48 (95% CI: 1.00-12.24, p-value < .05) with sensitivity and specificity of 65% each and 11.08 (95% CI: 2.62-46.83, p-value = .001) with the sensitivity of 82% and specificity of 70%, respectively. When combined together, MPI and CPR yielded an OR of 58.5 (95% CI: 4.58-746.57, p-value = .002) with a sensitivity of 56.5% and specificity of 95% in the FGR group. CONCLUSIONS: MPI in conjunction with CPR can be used together to predict adverse perinatal outcomes in FGR.

Utilidad de la ecografía Doppler en el diagnóstico, el pronóstico y el manejo de la restricción del crecimiento fetal: situación en Chile / Usefulness of Doppler ultrasound for the diagnosis, prognosis and management of fetal growth restriction: situation in Chile

INTRODUCCIÓN: La restricción del crecimiento fetal (RCF) se define como la disminución patológica de la tasa de crecimiento fetal, generalmente asociada a insuficiencia placentaria. Se diagnostica mediante ultrasonografía obstétrica y velocimetría Doppler, pero no existe un consenso global respecto a los parámetros referenciados. OBJETIVO: Brindar una revisión actualizada de la aproximación clínica de la RCF en Chile, enfocada en el uso de la ultrasonografía Doppler como herramienta fundamental para el diagnóstico, el pronóstico y el manejo de esta patología, y realizar una comparativa con respecto a otros países. MÉTODO: Se realizó una revisión con palabras clave en las bases de datos PubMed y SciELO. RESULTADOS: Se obtuvieron 89 referencias bibliográficas, logrando una revisión de datos actualizados del uso del Doppler en la RCF tanto en el mundo como en Chile. CONCLUSIONES: La Guía Perinatal 2015 publicada en Chile carece de actualización con los conocimientos y la evidencia científica más recientes. Sin embargo, concuerda en gran parte con los lineamientos y las pautas generales de manejo de la RCF de las diferentes guías clínicas analizadas. Las discrepancias entre las guías revisadas podrían explicarse por la gran variabilidad de la evidencia de los estudios científico-clínicos, los cuales es importante unificar a través de una guía que promueva una estandarización de la atención de la RCF en el país.

INTRODUCTION: Fetal growth restriction (FGR) is the pathological decrease in the fetal growth rate generally associated with placental insufficiency. Diagnosis is made by obstetric ultrasonography and Doppler velocimetry, assessing different biometric and hemodynamic parameters. However, there is no global consensus regarding the parameters to be referenced. OBJECTIVE: To provide an updated review of the FGR clinical approach in Chile, focused on the use of Doppler ultrasonography as a fundamental tool in the diagnosis, prognosis, and management of this pathology and to compare with other countries. METHOD: A literature search was conducted in the PubMed and SciELO databases, including relevant and updated articles. RESULTS: The search included 89 bibliographic references under which it was possible to make a review of the most current data on the use of Doppler in FGR both worldwide and in Chile. CONCLUSIONS: The 2015 Perinatal Guidelines published in Chile is not updated with the latest scientific evidence and knowledge. However, it largely agrees with international guidelines for FGR management. The discrepancies between the revised guidelines could be explained due to the variability of evidence from scientific-clinical studies, which are essential to unify for standardized care of FGR in the country.

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

INTRODUCTION: Ultrasound assessment of fetuses subjected to hyperglycemia is recommended but, apart from increased size, little is known about its interpretation, and the identification of which large fetuses of diabetic pregnancy are at risk is unclear. Newer markers of adverse outcomes, abdominal circumference growth velocity and cerebro-placental ratio, help to predict risk in non-diabetic pregnancy. Our study aims to assess their role in pregnancies complicated by diabetes. MATERIAL AND METHODS: This is a retrospective analysis of a cohort of singleton, non-anomalous fetuses of women with pre-existing or gestational diabetes mellitus, and estimated fetal weight at the 10th centile or above. Gestational diabetes was diagnosed by selective screening of at risk groups. A universal ultrasound scan was offered at 20 and 36 weeks of gestation. Estimated fetal weight, abdominal circumference growth velocity, presence of polyhydramnios, and cerebro-placental ratio were evaluated at the 36-week scan. A composite adverse outcome was defined as the presence of one or more of perinatal death, arterial cord pH less than 7.1, admission to Neonatal Unit, 5-minute Apgar less than 7, severe hypoglycemia, or cesarean section for fetal compromise. A chi-squared test was used to test the association of estimated fetal weight at the 90th centile or above, polyhydramnios, abdominal circumference growth velocity at the 90th centile or above, and cerebro-placental ratio at the 5th centile or below with the composite outcome. Logistic regression was used to assess which ultrasound markers were independent risk factors. Odds ratios of composite adverse outcome with combinations of independent ultrasound markers were calculated. RESULTS: A total of 1044 pregnancies were included, comprising 87 women with pre-existing diabetes mellitus and 957 with gestational diabetes. Estimated fetal weight at the 90th centile or above, abdominal circumference growth velocity at the 90th centile or above, cerebro-placental ratio at the 5th centile or below, but not polyhydramnios, were significantly associated with adverse outcomes: odds ratios (95% confidence intervals) 1.85 (1.21-2.84), 1.54 (1.02-2.31), 1.92 (1.21-3.30), and 1.53 (0.79-2.99), respectively. Only estimated fetal weight at the 90th centile or above and cerebro-placental ratio at the 5th centile or below were independent risk factors. The greatest risk (odds ratio 6.85, 95% confidence interval 2.06-22.78) was found where both the estimated fetal weight is at the 90th centile or above and the cerebro-placental ratio is at the 5th centile or below. CONCLUSIONS: In diabetic pregnancies, a low cerebro-placental ratio, particularly in a macrosomic fetus, confers additional risk.

Association of the Cerebro-Placental Ratio With Adverse Outcomes in Pregnancies Affected by Gestational Diabetes Mellitus.

OBJECTIVES: Cerebro-placental ratio (CPR) is a doppler tool contributes to clinical decision-making in pregnancies affected by small for gestational age weight (SGA). Pregnancies affected by gestational diabetes mellitus (GDM) tend to have higher newborn weight, but greater risk of adverse perinatal outcomes. We hypothesized that in GDM-complicated-pregnancies CPR will be associated with adverse perinatal outcomes even in the absence of SGA. METHODS: This prospective single-center cohort study included non-anomalous singleton pregnancies in women with GDM. Those with pre-pregnancy diabetes mellitus, hypertensive disorder or suspected SGA were excluded. Routine fetal sonographic assessment included CPR-defined as middle cerebral artery pulsatilty index/umbilical artery pulsatilty index. Masked CPR measurement closest to birth was used, classified as >10th (normal) or ≤10th centile (low). Primary outcome was a composite, consisting of stillbirth, Caesarean birth due to abnormal fetal heart rate pattern, 5-minute Apgar <7, cord arterial pH < 7.0, hypoxic ischemic encephalopathy, or NICU admission >24 hours. RESULTS: Of 281 participants, 24 (8.5%) had low CPR, at a mean gestational age of 36.3 weeks (IQR 34.0-37.4). Birthweight percentile was significantly lower among the low CPR group (35th [IQR 16-31] versus 60th [IQR 31-82]; P = .002). There was no statistically difference in the primary composite outcome between the groups (8.3% versus 7.0%, P = .68). Low CPR was significantly associated with a higher risk of neonatal hypoglycemia (adjusted odds ratio 3.2, 95% CI 1.2-8.3). CONCLUSION: In pregnancies affected by GDM, CPR ≤10th percentile was not associated with adverse perinatal outcome but was associated with neonatal hypoglycemia.

Role of Doppler Waveforms in Pregnancy-Induced Hypertension and Its Correlation With Perinatal Outcome.

Objectives The present study aims to measure the role of Doppler waveforms in pregnancy-induced hypertension (PIH) and its relationship with the perinatal outcome. Methods We have studied 50 pregnant women with PIH with gestational age (GA) 30-40 weeks for Umbilical Artery (UmA), Middle Cerebral Artery (MCA) and Uterine Artery (UtA) Doppler waveforms. Comparison between the various Doppler indices, i.e., Pulsatility Index (PI), Resistive Index (RI) and S/D ratio, with the severity of the disease and the perinatal outcomes were evaluated using appropriate statistical tests considering a threshold value of p-value <0.05 as significant. The Statistical Package for the Social Sciences (SPSS) version-16 (SPSS Inc, Chicago, USA) and MedCalc software (MedCalc Software Ltd, Ostend, Belgium) were used for data analysis. Results Half (50%) of the cases attributed to the 26 to 30 years age group were at 38 to 40 weeks of gestation. Out of the 50 patients, 68% were primigravida, and 74% had severe PIH. Mean UmA PI, mean MCA PI, mean MCA RI, and mean Cerebro Placental Ratio (CPR) were differed significantly among mild and severe PIH patients (p-value<0.05). Perinatal outcomes in 33 (66%) cases were adverse. The abnormal UmA RI, MCA RI, MCA PI, MCA S/D were significantly linked with poor pregnancy outcomes (p-value <0.05). PIH cases with the presence of early diastolic notch of UtA (p-value <0.01), abnormal PI CPR (p-value <0.001) and S/D CPR (p-value <0.003) were observed to have more adverse outcomes. PI CPR had the highest sensitivity (84.8%), and the existence of early diastolic notch of UtA and MCA-PI were most specific in diagnosing adverse perinatal outcomes. Conclusion CPR-PI is a valuable indicator of adverse perinatal outcomes in PIH. Doppler studies of multiple vessels may help manage high-risk pregnancies as it may provide helpful information about the fetus at risk of hypoxia and placental insufficiency.

Growth Velocity and Doppler Evaluation to Predict Nonreassuring Fetal Heart Rate at Birth in Low-Risk Women: A Prospective, Longitudinal Study.

INTRODUCTION: This study investigated whether fetal growth deceleration in term, appropriate-for-gestational-age (AGA) fetuses is associated with placental insufficiency and nonreassuring fetal heart rate (NRFHR) at birth. METHODS: In this prospective study, 246 low-risk, singleton pregnancies at term with AGA fetuses were recruited. Correlation between decreased growth velocity (decline in estimated fetal weight [EFW] percentile), low EFW (EFWQ1 = latest EFW between 11 and 25% percentiles), umbilical artery (UA) pulsatility index (PI), middle cerebral artery (MCA) PI, and cerebro-placental ratio (CPR) with cesarean and instrumental deliveries due to NRFHR were tested. RESULTS: The median change between fetal weight estimates (percentiles/week) was +0.49% (95% CI: -4 to +5%). Ten percent had decreased EFW percentile >3.5%/week. Fetal growth velocity/week was associated with MCA (r = 0.21, p < 0.001) and CPR (r = 0.24, p < 0.001) and inversely correlated with UA PI (r = -0.28, p < 0.001). NRFHR and cesarean section (CS) rates due to NRFHR were associated with decreased growth velocity, EFWQ1, and low CPR. The combination of abnormal CPR with decreased growth velocity occurred in 12 pregnancies, of which 5 (42%) had urgent CS due to NRFHR. The combination of abnormal CPR with EFWQ1 occurred in 9 pregnancies, of which 4 (44%) had urgent CS due to NRFHR. These combinations increased the likelihood ratio of CS due to NRFHR two-fold (8.41; 2.54-24.5) but did not significantly alter the number needed to treat by elective CS (3.78-4.68). CONCLUSION: Fetal growth velocity, EFW between 10 and 25th percentiles (EFWQ1), and abnormal CPR improves prediction of unplanned CS due to NRFHR among term AGA fetuses. This should be considered when counseling about the delivery method.

Cerebro-placental ratio as a prognostic factor of fetal outcome in pregnancy complicated by maternal sickle cell disease.

OBJECTIVES: To assess the role of the cerebro-placental ratio (CPR) in predicting adverse fetal outcomes among women with sickle cell disease (SCD). METHODS: A prospective cohort study at Korle-Bu Teaching Hospital, Accra, Ghana, between January and June 2016. Pregnant women with SCD at 34 gestational weeks or more underwent weekly fetal umbilical and middle cerebral artery Doppler assessment until delivery. Participants were categorized into two study arms based on CPR (<1.1 or ≥1.1). The primary outcome, a composite of adverse perinatal outcomes including intrauterine growth restriction, stillbirth, low birthweight, and neonatal intensive care unit admission, was compared between groups. RESULTS: Overall, 48 pregnant women with SCD were enrolled, and 5 had a fetus with CPR less than 1.1. Low CPR (<1.1) had a sensitivity and specificity of 29.4% and 100%, respectively, for predicting composite adverse perinatal outcomes. Sensitivity and specificity were, respectively, 100% and 93.5% for predicting stillbirth, and 40.2% and 97.4% for predicting low birthweight. Perinatal outcomes did not differ between the two major sickle cell genotypes (hemoglobin SS and hemoglobin SC). CONCLUSIONS: Among women with SCD, CPR less than 1.1 was associated with adverse perinatal outcomes, particularly low birthweight and stillbirth.

Prognostic Factors of Successful Cervical Ripening and Labor Induction in Late-Onset Fetal Growth Restriction.

OBJECTIVE: The aim of this work was to identify independent risk factors influencing the achievement of vaginal delivery among women undergoing labor induction for late-onset fetal growth restriction (FGR). METHODS: This was a retrospective cohort study of 201 singleton pregnancies with late-onset FGR (diagnosed >32 + 0 weeks) that required labor induction with cervical ripening from 37 + 0 weeks, either with dinoprostone (from 2014 to 2015) or Foley balloon (from 2016 to 2018). Independent factors for successful vaginal delivery were identified. A prediction model of vaginal delivery with the identified factors was made using logistic regression and bootstrapping with 1,000 re-samples performed for bias correction. RESULTS: Perinatal results were more favorable in the vaginal delivery group, with significantly lower neonatal admission rates (4.0 vs. 13.7%) and lower composite neonatal morbidity (4.0 vs. 15.7%). The labor induction method (Foley balloon), higher cerebro-placental ratio, lower pre-gestational BMI, and absence of pre-eclampsia were identified as independent factors associated to vaginal delivery. The area under the curve of the model was of 0.75 (95% CI 0.70-0.79). CONCLUSIONS: The use of a Foley balloon is the only modifiable risk factor to improve the chances of vaginal delivery when attempting induction of labor in singleton pregnancies with late-onset FGR.

Intra- and Interobserver Reproducibility of Third Trimester Middle Cerebral Artery Pulsatility Index Measurement: A Prospective Cross-Sectional Study.

BACKGROUND: Middle cerebral artery (MCA) pulsatility index (PI) Doppler in the third trimester of pregnancy is increasingly used. OBJECTIVES: The aim of the study was to investigate intra- and interobserver reproducibility of MCA PI in the third trimester. METHOD: Singleton pregnancies between 30+0 and 40+0 weeks were recruited. MCA Doppler velocimetry measurements were performed prospectively, independently, and blindly. Intra- and interobserver reproducibility was assessed by concordance correlation coefficient (CCC) and intraclass correlation coefficient (ICC); Bland-Altman plots were built, and limits of agreement (LoA) were calculated. Results were interpreted according to the cutoff set by the True Reproducibility of Ultrasound Techniques Review. RESULTS: We enrolled 101 patients. ICCs for intraobserver reproducibility were 0.84 and 0.78 for raw values and percentiles, respectively; CCCs were 0.72 and 0.64. For interobserver reproducibility ICCs were 0.84 and 0.78, CCCs 0.72 and 0.63. According to the chosen criteria, these values show a poor-moderate reproducibility of third trimester MCA PI. Cohen's Kappa coefficients were 0.59 and 0.42, indicating a moderate agreement in discriminating normal and abnormal values. CONCLUSIONS: Intra- and interobserver reproducibility of third trimester MCA PI, as assessed by ICC, CCC, and LoA, is far from satisfactory. This should be taken into account before taking clinical decisions.

Does Uterine Doppler Add Information to the Cerebroplacental Ratio for the Prediction of Adverse Perinatal Outcome at the End of Pregnancy?

OBJECTIVE: To evaluate whether the addition of the mean uterine arteries pulsatility index (mUtA PI) to the cerebroplacental ratio (CPR) improves its ability to predict adverse perinatal outcome (APO) at the end of pregnancy. METHODS: This was a prospective study of 891 fetuses that underwent an ultrasound examination at 34-41 weeks. The CPR and the mUtA PI were converted into multiples of the median (MoM) and the estimated fetal weight (EFW) into centiles according to local references. APO was defined as a composite of abnormal cardiotocogram, intrapartum pH requiring cesarean section, 5' Apgar score <7, neonatal pH <7.10 and admission to pediatric care units. The accuracies of the different parameters were evaluated alone and in combination with gestational characteristics using univariate and multivariate analyses by means of the Akaike Information Criteria (AIC) and the area under the curve (AUC). Finally, a comparison was similarly performed between the CPR and the cerebro-placental-uterine ratio (CPUR; CPR/mUtA PI) for the prediction of APO. RESULTS: The univariate analysis showed that CPR MoM was the best parameter predicting APO (AIC 615.71, AUC 0.675). The multivariate analysis including clinical data showed that the best prediction was also achieved with the CPR MoM (AIC 599.39, AUC 0.718). Moreover, when EFW centiles were considered, the addition of UtA PI MoM did not improve the prediction already obtained with CPR MoM (AIC 591.36, AUC 0.729 vs. AIC 589.86, AUC 0.731). Finally, the prediction by means of CPUR did not improve that of CPR alone (AIC 623.38, AUC 0.674 vs. AIC 623.27, AUC 0.66). CONCLUSION: The best prediction of APO at the end of pregnancy is obtained with CPR whatever is the combination of parameters. The addition of uterine Doppler to the information yielded by CPR does not result in any prediction improvement.

Assessment of reproducibility and repeatability of cerebro-placental ratio.

INTRODUCTION: To test the reproducibility and repeatability of the cerebro-placental ratio. STUDY DESIGN: Pregnant women with a singleton pregnancy and secure dating were invited to participate after 24 weeks of pregnancy. Using recommended technique, umbilical artery PI was measured from the free loop of the umbilical cord and from the fetal end by one examiner in a state of fetal quiescence, generating four measurements per fetus. Fetal middle cerebral artery PI was also obtained. Cerebro-placental ratio (CPR) was calculated as MCA PI/Umbilical artery PI. Variability of the CPR on the two sampling occasions was tested using Pitman test of equality of variance for related samples. The difference between the two sets of CPR measurements was plotted against the mean to generate 95% limits of agreement. RESULTS: A total of 158 women were recruited. The mean CPR was significantly lower when the umbilical artery PI was obtained at the para-vesical site, than when it in obtained from a free loop (p < 0.001). No significant correlation was seen between gestational age and CPR, when the umbilical artery PI was measured from the para-vesical site (r = -0.079, p = 0.323) or the free loop (r = -0.103, p = 0.198). Total variance of the CPR using the umbilical artery free loop was 0.286, and that using the para-vesical site of the umbilical artery was 0.164. Pitman's test showed that the total variability of CPR at the two sites was significantly different (r = 0.254, p < 0.001). The variability of CPR was significantly lower if the umbilical artery PI measurement was taken at the fetal end than that in the free loop. CONCLUSION: The mean CPR site was significantly lower when the umbilical artery PI was obtained at the para-vesical than in the free loop. Measurement site for the umbilical artery PI contributes to a significant proportion to the total variability of the cerebro-placental ratio. CPR measurements should include umbilical artery PI measurements at the para-vesical site rather than the free loop of the umbilical cord in order to improve repeatability. Appropriate reference ranges for the interpretation of CPR will be needed.

Reference centiles for the middle cerebral artery and umbilical artery pulsatility index and cerebro-placental ratio from a low-risk population - a Generalised Additive Model for Location, Shape and Scale (GAMLSS) approach.

OBJECTIVE: The primary aim of this study was to create reference ranges for the fetal Middle Cerebral artery Pulsatility Index (MCA PI), Umbilical Artery Pulsatility Index (UA PI) and the Cerebro-Placental Ratio (CPR) in a clearly defined low-risk cohort using the Generalised Additive Model for Location, Shape and Scale (GAMLSS) method. METHODS: Prospectively collected cross-sectional biometry and Doppler data from low-risk women attending the Mater Mother's Hospital, Maternal and Fetal Medicine Department in Brisbane, Australia between January 2010 and April 2017 were used to derive gestation specific centiles for the MCA PI, UA PI and CPR. All ultrasound scans were performed between 18 + 0 and 41 + 6 weeks gestation with recorded data for the MCA PI and/or UA PI. The GAMLSS method was used for the calculation of gestational age-adjusted centiles. Distributions and additive terms were assessed and the final model was chosen on the basis of the Global Deviance, Akaike information criterion (AIC) and Schwartz bayesian criterion (SBC), along with the results of the model and residual diagnostics as well as visual assessment of the centiles themselves. RESULTS: Over the study period 6013 women met the inclusion criteria. The MCA PI was recorded in 4473 fetuses, the UA PI in 6008 fetuses and the CPR was able to be calculated in 4464 cases. The centiles for the MCA PI used a fractional polynomial additive term and Box-Cox t (BCT) distribution. Centiles for the UA PI used a cubic spline additive term with BCT distribution and the CPR used a fractional polynomial additive term and a BCT distribution. CONCLUSION: We have created gestational centile reference ranges for the MCA PI, UA PI and CPR from a large low-risk cohort that supports their applicability and generalisability.

The fetal cerebro-placental ratio in diabetic pregnancies is influenced more by the umbilical artery rather than middle cerebral artery pulsatility index.

OBJECTIVE: This study aimed to assess the relationship between the cerebro-placental ratio (CPR) and intrapartum and perinatal outcomes in pregnancies complicated by pre-existing insulin dependent diabetes (pT1DM) mellitus, pre-existing non-insulin dependent diabetes mellitus (pT2DM) and gestational diabetes mellitus (GDM). STUDY DESIGN: This was a retrospective cohort study of 1281 women with diabetes mellitus birthing at the Mater Mothers' Hospital in Brisbane between 2007 and 2015. The CPR in non-anomalous singleton fetuses was measured between 34+0 and 36+6 weeks gestation and compared between types of DM treatment groups and correlated with intrapartum and perinatal outcomes. RESULTS: Of the study cohort, 9.7% (124/1281) had pT1DM, 5.3% (68/1281) had pT2DM and 85.0% (1089/1281) had GDM. Of women with pT2DM and GDM, 61.8% (42/68) and 28.9% (315/1089) respectively, required insulin during pregnancy. Women with pT1DM had an increased odds of having a CPR <5th centile (OR 3.73, 95%CI: 1.90-6.96, p=0.0001) or a CPR <10th centile (OR 3.01, 95% CI: 1.80-4.91, p<0.0001) respectively. The odds of a UA PI >90th centile (OR 2.69, 95% CI: 1.60-4.39, p=0.0001) was higher in the pT1DM cohort. There was however no significant difference in the mean MCA PI between the three groups. Stratification by CPR centiles (<10th centile vs. ≥10th centile) demonstrated a lower birth weight in the CPR <10th centile cohort for all DM categories. The proportion of neonates with birth weights <10th centile were higher in the CPR <10th centile cohort with the GDM cohort having an odds ratio of 8.28 (95% CI 4.22-16.13, p<0.0001) of this complication. The CPR <10th centile cohort also had a greater proportion of adverse composite neonatal outcome regardless of type of DM. CONCLUSIONS: Regardless of the type of DM, a low CPR was associated with poorer neonatal outcomes. Women with pT1DM also had the highest mean UA PI and lowest mean CPR despite no difference in the mean MCA PI between the three groups.

The association between a low cerebro-umbilical ratio at 30-34 weeks gestation, increased intrapartum operative intervention and adverse perinatal outcomes.

INTRODUCTION: The aim of this study was to investigate the relationship between the cerebro-umbilical ratio (CUR), measured at 30-34 weeks, and adverse intrapartum and perinatal outcomes. METHODS: This was a retrospective cross-sectional cohort study of women delivering at the Mater Mothers' Hospital in Brisbane, Australia. Fetal Doppler indices for 1224 singleton pregnancies were correlated with maternal demographics and intrapartum and perinatal outcomes. Only women who attempted vaginal delivery were included in the study. RESULTS: Infants delivered by emergency cesarean section for fetal compromise had the lowest median CUR, 1.65 (IQR 1.17-2.12), compared to any other delivery group. The proportion of infants with a CUR ≤1 who required emergency cesarean section for fetal compromise was 33.3% compared to 9.3% of infants with a CUR >1 (adjusted OR 6.92 (95% CI 2.04-25.75), p<0.001). However, the detection rate of CUR ≤1 as a predictor for emergency cesarean delivery for fetal compromise was poor (18.9%). Detection rates increased in cohorts of infants born within two weeks of the scan or with birth weights <10th centile or <5th centile. Additionally, a CUR ≤1 was associated with lower median birth weight, higher rates of admission to the neonatal critical care unit and increased neonatal mortality. DISCUSSION: This study suggests that a CUR ≤1, measured at 30-34 weeks, is associated with a greater risk of emergency cesarean delivery for fetal compromise and a number of other adverse perinatal outcomes. The association was strongest in low birth weight babies.

Predicting intrapartum fetal compromise using the fetal cerebro-umbilical ratio.

INTRODUCTION: The aim of this study was to explore the association between the cerebro-umbilical ratio measured at 35-37 weeks and intrapartum fetal compromise. METHODS: This retrospective cross sectional study was conducted at the Mater Mothers' Hospital in Brisbane, Australia. Maternal demographics and fetal Doppler indices at 35-37 weeks gestation for 1381 women were correlated with intrapartum and neonatal outcomes. RESULTS: Babies born by caesarean section or instrumental delivery for fetal compromise had the lowest median cerebro-umbilical ratio 1.60 (IQR 1.22-2.08) compared to all other delivery groups (vaginal delivery, emergency delivery for failure to progress, emergency caesarean section for other reasons or elective caesarean section). The percentage of infants with a cerebro-umbilical ratio <10th centile that required emergency delivery (caesarean section or instrumental delivery) for fetal compromise was 22%, whereas only 7.3% of infants with a cerebro-umbilical ratio between the 10th-90th centile and 9.6% of infants with a cerebro-umbilical ratio > 90th centile required delivery for the same indication (p < 0.001). A lower cerebro-umbilical ratio was associated with an increased risk of emergency delivery for fetal compromise, OR 2.03 (95% CI 1.41-2.92), p < 0.0001. DISCUSSION: This study suggests that a low fetal cerebro-umbilical ratio measured at 35-37 weeks is associated with a greater risk of intrapartum compromise. This is a relatively simple technique which could be used to risk stratify women in diverse healthcare settings.