Fetal middle cerebral artery and umbilical artery pulsatility index: effects of maternal characteristics and medical history

Third Trimester Umbilical Arterial Pulsatility Index is Associated with Neurodevelopmental Outcomes at 2-Years in Major Congenital Heart Disease

Major congenital heart disease (CHD) is associated with impaired neurodevelopment (ND), partly from prenatal insults. In this study we explore associations between 2nd and 3rd trimester umbilical (UA) and middle cerebral artery (MCA) pulsatility index (PI = systolic-diastolic velocities/mean velocity) in fetuses with major CHD and 2-year ND and growth outcomes. Eligible patients included those with a prenatal diagnosis of CHD from 2007 to 2017 without a genetic syndrome who underwent previously defined cardiac surgeries and 2-year biometric and ND assessments in our program. UA and MCA-PI Z-scores at fetal echocardiography were examined for relationships with 2-year Bayley Scales of Infant and Toddler Development and biometric Z-scores. Data from 147 children was analyzed. Second and 3rd trimester fetal echocardiograms were performed at 22.4 ± 3.7 and 34.7 ± 2.9 weeks (mean ± SD), respectively. Multivariable regression analysis showed an inverse relationship between 3rd trimester UA-PI for all CHD and cognitive - 1.98 (- 3.37, - 0.59), motor - 2.57 (- 4.15, - 0.99), and language - 1.67 (- 3.3, - 0.03) (effect size and 95th confidence interval) ND domains (p < 0.05), with the strongest relationships in the single ventricle and hypoplastic left heart syndrome subgroups. No association was found for 2nd trimester UA-PI or any trimester MCA-PI and ND or between UA or MCA-PI and 2-year growth parameters. Increased 3rd trimester UA-PI, reflecting an altered late gestation fetoplacental circulation, relates to worse 2-year ND in all domains.

Impact of Maternal-Fetal Environment on Mortality in Children With Single Ventricle Heart Disease

BACKGROUND

Children with single ventricle heart disease have significant morbidity and mortality. The maternal–fetal environment (MFE) may adversely impact outcomes after neonatal cardiac surgery. We hypothesized that impaired MFE would be associated with an increased risk of death after stage 1 Norwood reconstruction.

METHODS AND RESULTS

We performed a retrospective cohort study of children with hypoplastic left heart syndrome (and anatomic variants) who underwent stage 1 Norwood reconstruction between 2008 and 2018. Impaired MFE was defined as maternal gestational hypertension, preeclampsia, gestational diabetes, and/or smoking during pregnancy. Cox proportional hazards regression models were used to investigate the association between impaired MFE and death while adjusting for confounders. Hospital length of stay was assessed with the competing risk of in‐hospital death. In 273 children, the median age at stage 1 Norwood reconstruction was 4 days (interquartile range [IQR], 3–6 days). A total of 72 children (26%) were exposed to an impaired MFE; they had more preterm births (18% versus 7%) and a greater percentage with low birth weights <2.5 kg (18% versus 4%) than those without impaired MFE. Impaired MFE was associated with a higher risk of death (hazard ratio [HR], 6.05; 95% CI, 3.59–10.21; P<0.001) after adjusting for age at surgery, Hispanic ethnicity, genetic syndrome, cardiac diagnosis, surgeon, and birth era. Children with impaired MFE had almost double the risk of prolonged hospital stay (HR, 1.95; 95% CI, 1.41–2.70; P<0.001).

CONCLUSIONS

Children exposed to an impaired MFE had a higher risk of death following stage 1 Norwood reconstruction. Prenatal exposures are potentially modifiable factors that can be targeted to improve outcomes after pediatric cardiac surgery.

Placental functional assessment and its relationship to adverse pregnancy outcome: comparison of intravoxel incoherent motion (IVIM) MRI, T2-relaxation time, and umbilical artery Doppler ultrasound

BACKGROUND

Early identification of placental insufficiency can lead to appropriate treatment selections and can improve neonates' outcomes. Possible contributions of magnetic resonance imaging (MRI) have been suggested.

PURPOSE

To evaluate the prognostic capabilities of placental intravoxel incoherent motion (IVIM) parameters and T2-relaxation time, and their correlation with fetal growth and adverse outcomes, comparing umbilical artery (UmA) pulsatility index (PI).

MATERIAL AND METHODS

A total of 68 singleton pregnancies at 24-40 weeks of gestation underwent placental MRI and were reviewed retrospectively. UmA-PI was measured using Doppler ultrasound by obstetricians. IVIM parameters (Dfast, Dslow, and f) were calculated with a Bayesian model fitting. First, the associations between gestational age (GA) with placental IVIM parameters, T2-relaxation time, and placental thickness (PT) were evaluated. Second, IVIM parameters, T2 value (Z-score), PT (Z-score), and UmA-PI (Z-score) were compared between ( 1) those delivering small for gestational age (SGA) and appropriate for gestational age (AGA) neonates, ( 2) emergency cesarean section (ECS), and non-ECS, and ( 3) preterm birth and full-term birth.

RESULTS

Low birth weight was observed in 15/68 cases (22%). GA was significantly associated only with T2-relaxation time and PT. SGA was significantly associated with T2 value (Z-score), f, and UmA-PI (Z-score). In the ECS groups, T2 value (Z-score), f, and Dfast were significantly lower than those in non-ECS groups. All IVIM parameters and T2 values (Z-score) showed significantly lower scores in the preterm birth group.

CONCLUSION

Placental f and T2 value (Z-score) had significant associations with low birth weight and clinical adverse outcomes and could be potential imaging biomarkers of placental insufficiency.

Intra-observer variability of Doppler measurements in umbilical artery (UA) and middle cerebral artery (MCA) in uncomplicated term pregnancies

OBJECTIVE

To evaluate the intra-observer variability of the middle cerebral artery (MCA) and umbilical artery (UA) Doppler measurement taken under optimal conditions in term, uncomplicated pregnancies.

METHODS

A prospective study on uncomplicated singleton term pregnancies was performed. Multiple Doppler measurements were taken in the MCA and the UA by one examiner. Intra-rater agreement was calculated. Doppler indices were correlated to fetal biometric parameters and to gestational age.

RESULTS

One hundred patients were recruited. MCA indices were found to have the highest strength of intra-rater/observer agreement (K = 0.888) versus only a "good" agreement for UA pulsatility index (PI) (K = 0.755).The MCA-PI was significantly correlated with BPD (r = -0.198, p = .047), EFW (r = -0.241, p = .01) and birthweight (r = -0.208, p = .03). A statistically significant decrease was found in the MCA PI (r = -.422, p < .001) and in the CPR (r = -0.444, p < .001) with advancing pregnancy, between 37 and 42 weeks gestation. The UA PI did not change significantly (p = .099) during this period.

CONCLUSIONS

MCA PI measured at term is reproducible with a high ICC. MCA PI significantly decreases with advancing gestation at term. No correlation was found between Doppler measurements and time to delivery.

The placenta as the window to congenital heart disease

PURPOSE OF REVIEW

There is an increasing recognition that structural abnormalities and functional changes in the placenta can have deleterious effects on the development of the fetal heart. This article reviews the role of the placenta and the potential impact of placental insufficiency on fetuses with congenital heart disease.

RECENT FINDINGS

The fetal heart and the placenta are directly linked because they develop concurrently with shared regulatory and signaling pathways. Placental disease is more common in pregnancies carrying a fetus with congenital heart disease and the fetal response to placental insufficiency may lead to the postnatal persistence of cardiac remodeling. The mechanisms underlying this placental-fetal axis of interaction potentially include genetic factors, oxidative stress, chronic hypoxia, and/or angiogenic imbalance.

SUMMARY

The maternal-placental-fetal circulation is critical to advancing our understanding of congenital heart disease. We must first expand our ability to detect, image, and quantify placental insufficiency and dysfunction in utero. Elucidating the modifiable factors involved in these pathways is an exciting opportunity for future research, which may enable us to improve outcomes in patients with congenital heart disease.

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.

Fetal Umbilical Arterial Pulsatility Correlates With 2-Year Growth and Neurodevelopmental Outcomes in Congenital Heart Disease

BACKGROUND

Children with congenital heart disease (CHD) are at risk of adverse long-term neurodevelopmental outcomes, believed to be, in part, secondary to prenatal insults. Placental pathology and altered fetal middle cerebral arterial (MCA) flow suggestive of brain sparing have been documented in fetal CHD. In the present study we investigated the relationship between MCA and umbilical arterial (UA) flow patterns in fetal transposition of the great arteries (d-TGA) and hypoplastic left heart syndrome (HLHS) and growth and 2-year neurodevelopmental outcomes.

METHODS

We included children with d-TGA and HLHS who had third-trimester fetal echocardiograms between 2004 and 2014, at which time umbilical artery (UA) and MCA pulsatility indices (PIs) were measured, and who underwent 2-year growth and neurodevelopmental assessments.

RESULTS

We identified 24 children with d-TGA and 36 with HLHS. Mean age at fetal echocardiography was 33.8 ± 3.5 weeks. At 2-year follow-up, head circumference z score (standard deviation [SD]) was -0.09 (1.07) and 0.17 (1.7) for the d-TGA and HLHS groups, respectively. Bayley III mean (SD) cognitive, language, and motor scores were 97.7 (10.8), 94.7 (13.4), and 98.6 (8.6) for the d-TGA group and 90.3 (13.9), 87.2 (17.5), and 85.3 (16.2) for the HLHS group. On multivariate linear regression analysis, UA-PI was associated (effect sizes [95% CI]) with length (-1.45 [-2.7, -0.17], P = 0.027), weight (-1.46 [-2.6 to -0.30], P = 0.015) and cognitive scores (-14.86 [-29.95 to 0.23], P = 0.05) at 2 years of age. MCA PI showed no statistically significant correlation.

CONCLUSIONS

In fetal d-TGA and HLHS, a higher UA-PI in the third trimester, suggestive of placental insufficiency-but not MCA-PI-is associated with worse 2-year growth and neurodevelopment.

Fetal Middle Cerebral Artery Pulsatility Index in No-Risk Pregnancies: Effects of Auditory Stimulation and Pregnancy Order

Pulsatility index (PI) values in a fetal middle cerebral artery (MCA) were compared in no-risk pregnancies to examine the differences related to auditory stimulation test and pregnancy order. The study included 196 women with no-risk pregnancies selected from the database of more than 1000 pregnant women divided into two groups. Group 1 consisted of 98 nulliparous women (C1 = 98) and Group 2 consisted of 98 parous women (C2 = 98). All pregnant women were of comparable age and fetal gestational age (GA) when MCA-PI values were recorded. Measurements of PI values in fetal MCA were obtained before and immediately after the application of fetal auditory stimulation test. The MCA-PI measuring was conducted in the period between the 36th and the 41st week of GA. The results showed that PI baseline values and PI values after defined auditory stimulation were significantly different when measured in nulliparous women compared to parous women (p = 0.001; p = 0.003, respectively), while no group differences were observed in relative PI value changes due to auditory stimulation. These findings suggest that hemodynamic changes in fetal MCA caused by defined auditory stimulation measured by PI value changes may be valuable in the assessment of fetal auditory perception functionality and its development.

Reference Centile Chart of Fetal Cerebroplacental Doppler from 24 to 40 Weeks Gestation in Indian Population

Objective

Construction of reference centile chart of middle cerebral (MCA) and umbilical artery (UA) Doppler along with cerebroplacental ratio from 24 to 40 weeks gestation in Indian population.

Method

It was a cross-sectional observational study; antenatal women between 24 and 40 weeks gestation underwent the MCA and UA Doppler. The centile charts for MCA, UA and cerebroplacental ratio (CPR) were derived.

Results

Total 300 antenatal women were included; the MCA PI, RI, S/D ratio values showed a parabolic curve with the peak at 33-35 weeks; the umbilical artery Doppler and cerebroplacental ratio showed a linear decrease with increasing gestational age. The regression analysis showed a weak correlation between the Doppler parameters and the gestational age. The MOM values of all Doppler parameters, across the gestational age, were also derived.

Conclusion

The constructed MCA, UA and CPR charts along with their MOM values could be used as reference for the regional population.

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

OBJECTIVES

To develop gestational age-based reference ranges for the pulsatility index in the umbilical artery (UA-PI) and fetal middle cerebral artery (MCA-PI) and the cerebroplacental ratio (MCA-PI/UA-PI), and to examine the maternal characteristics and medical history that affect these measurements.

METHODS

This was a cross-sectional study of 72 387 pregnancies undergoing routine ultrasound examination at 20 + 0 to 22 + 6 weeks' gestation (n = 3712), 31 + 0 to 33 + 6 weeks (n = 29 035), 35 + 0 to 36 + 6 weeks (n = 37 252) or 41 + 0 to 41 + 6 weeks (n = 2388). For the purpose of this study, we included data for only one of the second- or third-trimester visits. The inclusion criteria were singleton pregnancy, dating by fetal crown-rump length at 11 + 0 to 13 + 6 weeks' gestation, live birth of a morphologically normal neonate and ultrasonographic measurements by sonographers who had received the Fetal Medicine Foundation Certificate of Competence in Doppler ultrasound. Since the objectives of the study were to establish reference ranges, rather than normal ranges, and to examine factors from maternal characteristics and medical history that affect these measurements, we included all pregnancies having routine ultrasound examinations, irrespective of whether the mother had a pre-existing medical condition, such as diabetes mellitus, or a pregnancy complication, such as pre-eclampsia or suspected fetal growth restriction. Median and SD models were fitted between UA-PI, MCA-PI and CPR and gestational age. Assessment of goodness of fit of the models was by inspection of quantile-to-quantile (Q-Q) plots of Z-scores calculated using the mean and SD models. The distributions of MCA-PI, UA-PI and CPR Z-scores were examined in relation to maternal characteristics and medical history.

RESULTS

The relationship between the median and gestational age was linear for UA-PI and cubic for MCA-PI and CPR and the SD was log quadratic for all three. MCA-PI and CPR increased with gestational age from 20 weeks' gestation to reach a peak at around 32 and 34 weeks, respectively, and decreased thereafter, whereas UA-PI decreased linearly with gestational age from 20 to 42 weeks. Compared to the general population, significant deviations in multiples of the median values of UA-PI, MCA-PI and CPR were observed in subgroups of maternal age, body mass index, racial origin, method of conception and parity.

CONCLUSION

This study established new reference ranges for UA-PI, MCA-PI and CPR, according to gestational age, and reports maternal characteristics and medical history that affect these measurements. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

The relation of fetal colon and rectum diameters with labor in healthy late-third trimester pregnancies

OBJECTIVE

To investigate the associations of fetal colon-rectum diameters with labor and fetal distress or meconium passage in healthy pregnancies in the late 3rd trimester.

STUDY DESIGN

A total of 162 healthy, singleton pregnant women at ≥36^0/7 weeks who were in the latent-phase of labor (n = 69) or those not in labor (n = 93, controls) at the time of ultrasound examination were enrolled. Fetal colon (ascending, transverse, descending, sigmoid) and rectum diameters, Doppler indices of materno-fetal vessels were measured. Data were analyzed according to the mode of delivery.

RESULTS

Fetal colon-rectum diameters were smaller in women in labor compared to controls (p = 0.001). Positive correlations were observed between fetal colon-rectum diameters and interval between ultrasound and labor onset in the control group except for those who had scheduled cesarean sections (C/S) (p = 0.001). Similar colon-rectum measurements were obtained in fetuses delivered via cesarean section due to fetal distress or to other indications (p > 0.05). In women who had uterine contractions during ultrasound examination; later delivered by vaginal route, no association was observed between Apgar scores and colon-rectum diameters during latent-phase (p > 0.05), and also there were significant positive correlations between different segments of colon-rectum diameters and duration of neonatal meconium passage (p < 0.05).

CONCLUSION

Fetal colon and rectum diameters are smaller during labor and the measurements tend to diminish as the labor approaches, but do not indicate fetal distress.

Amnioinfusion for variable decelerations caused by umbilical cord compression without oligohydramnios but with the sandwich sign as an early marker of deterioration

We report prophylactic amnioinfusion (AI) for variable decelerations in umbilical cord compression without oligohydramnios as an early sign of deterioration. We performed a transabdominal AI in cases without oligohydramnios using the ultrasonography findings of umbilical cord compression (i.e. sandwich sign [SWS]) and variable decelerations (VD) in a foetal heart rate. Thirteen cases and 21 AIs were analysed. Nine (69%) cases were of a foetal growth restriction and 4 (31%) had umbilical hyper-coiled cords. VD frequency (p < .0001), umbilical artery pulsatility index (PI) (p < .01) and ductus venous PI (0.66 vs. 0.48; p < .05) significantly decreased, and an umbilical venous (UV) flow volume (121 vs. 197 ml/min/kg; p < .05) significantly increased after AI. The umbilical artery diastolic blood flow abnormalities and UV pulsation improved. In conclusion, AI improves the umbilical cord compression even without oligohydramnios. The SWS is an important marker of deterioration to severe oligohydramnios and latent foetal damage. IMPACT STATEMENT What is already known on this subject? Antepartum variable decelerations due to umbilical cord compression are significantly associated with the deceleration in labour. In particular, foetal hypoxia leads to other adverse events such as foetal distress, hypoxic-ischemic encephalopathy, and pulmonary arterial hypertension after birth. Amnioinfusion has been shown to be effective in patients who also have oligohydramnios. What do the results of this study add? Amnioinfusion may be effective in the cases with ultrasonography findings of umbilical cord compression (i.e. sandwich sign) and in cases with variable decelerations in foetal heart rate, but without oligohydramnios. What are the implications of these findings for clinical practice and/or further research? Amnioinfusion may be helpful to prevent adverse events including oligohydramnios and anhydroamnios.

Prognostic accuracy of cerebroplacental ratio for adverse perinatal outcomes in pregnancies complicated with severe pre-eclampsia; a prospective cohort study

OBJECTIVE

The current study aims to assess the efficacy of fetal middle cerebral artery/umbilical artery pulsatility index ratio (cerebroplacental ratio CPR) in predicting the occurrence of adverse perinatal outcomes in pregnancies complicated with severe pre-eclampsia.

MATERIALS AND METHODS

This cohort study included 100 pregnant women between 34 and 40 weeks of gestation attended the labor ward and diagnosed with severe pre-eclampsia. Doppler evaluation was carried out to measure the CPR. Apgar score and fetal umbilical artery pH were assessed within 5 min of delivery. The rate of neonatal intensive care unit (NICU) admission was obtained.

RESULTS

Apgar score at 5 min >7 was in 82 cases (82%) and 12 cases (12%) scored < 7. Fetal blood PH was >7.2 in 67% of cases while 33% of cases had PH <7.2. As regard the NICU admission; 66% of neonates did not need admission while 34% of neonates were admitted to the NICU. There was a significant association between CPR and low Apgar score at 5 min (P < 0.001). The sensitivity of CPR in detection of Apgar score <7 was 50%, and specificity 88.1%. CPR had a poor predictive value of the low umbilical artery PH <7.2 (P = 0.318) with 43.75% sensitivity and 69.05% specificity. There was a significant association between CPR and NICU admission (P = 0.009).

CONCLUSIONS

Adding CPR ratio to routine antepartum fetal surveillance from 34 weeks gestation may help with patient counseling regarding adverse neonatal outcomes for women with severe pre-eclampsia as there is a strong correlation between it and adverse neonatal outcomes.

Antenatal ultrasound value in risk calculation for Autism Spectrum Disorder: A systematic review to support future research

There is a growing research interest on the antenatal features of children with neurodevelopmental disorders. Indeed, it has been proved that the neurodevelopment is, at least partly, affected by processes occurring in fetal life and that the early neurodevelopmental disorders identification is essential to optimize long-term outcomes. This systematic review aims to summarize findings on antenatal ultrasound data, which are or might be considered early risk indexes of postnatal social impairments. We conducted systematic searches in Pubmed and PsychINFO databases to identify studies including fetal ultrasound measurements and postnatal neurodevelopmental outcome assessment. The bibliographic search included 3203 articles but after the assessment of the eligibility conducted by two independent researchers, only 26 studies were selected. Some alterations in ultrasound antenatal measurements (such as biophysical data, nuchal thickness and enlargement of cerebral ventricles) have been associated to autism spectrum disorder. However, data are still limited, controversial and not specific. Reported data are here discussed to strongly support studies on fetuses at high risk for autism spectrum disorder.

Variations from morning to afternoon of middle cerebral and umbilical artery blood flow, and fetal heart rate variability, and fetal characteristics in the normally developing fetus

OBJECTIVE

To determine if there are changes in maternal uterine blood flow, fetal brain blood flow, fetal heart rate variability, and umbilical blood flow between morning (AM) and afternoon (PM) in healthy, uncomplicated pregnancies.

STUDY DESIGN

In this prospective study, 68 uncomplicated singleton pregnancies (mean 35 + 0.7 weeks gestation) underwent a standard observational protocol at both 08:00 (AM) and 13:30 (PM) of the same day. This protocol included Doppler measurements of uterine, umbilical, and fetal middle cerebral artery (MCA) volume flow parameters (flow, HR, peak systolic velocity [PSV], PI, and RI) followed by computerized cardiotocography. Standard descriptive statistics, χ² and t tests were used where appropriate. P < .05 was considered significant.

RESULTS

A significant increase in MCA flow and MCA PSV was observed in the PM compared to the AM. This was accompanied by a fall in MCA resistance. Higher umbilical artery resistance indices were also observed in the PM compared to AM. In contrast, fetal heart rate characteristics, maternal uterine artery Doppler flow and resistance indices did not vary significantly between the AM and PM.

CONCLUSION

In normal pregnancies, variations in fetal cerebral and umbilical blood flow parameters were observed between AM and PM independent of other fetal movements or baseline fetal heart rate. In contrast, uterine flow parameters remained stable across the day. These findings may have implications for the use of serial Doppler parameters used to guide clinical management in high-risk pregnancies.

Utility of Doppler parameters at 36-42 weeks' gestation in the prediction of adverse perinatal outcomes in appropriate-for-gestational-age fetuses

Aim

To investigate the potential value of Doppler ultrasound and to assess cerebroplacental ratio (CPR) in the prediction of adverse perinatal outcome defined as Apgar score < 7 at 1 minute.

Material and methods

This was a retrospective cross-sectional study in selected pregnant women undergoing an ultrasound examination between 36 and 42 weeks of gestation. We measured estimated fetal weight (EFW), mean umbilical artery pulsatility index (UA PI), mean middle cerebral artery pulsatility index (MCA PI), CPR, and Apgar score in 1 minute. Multiples of medians (MoM) were calculated for MCA PI and UA PI.

Results

The study group consisted of 446 women, 236 were primipara and 210 were multipara. The average age was 29.6 years (range 16–46 years). The average week of delivery is 39.5 weeks of gestation (range 36–42). Mean MCA PI and UA PI were 1.3 (0.1–2.45) and 0.8 (0.39–1.66), respectively. The mean values were 1.03 (0.1–1.9) for MCA PI MoM and 1.04 (0.5–2.1) for UA PI MoM. Primiparas had lower values of MCA PI (1.27 vs. 1.34), MCA PI MoM (1.00 vs. 1.05), CPR (1.62 vs. 1.73), EFW (3479.53 g vs. 3579.25 g) and birth weight (3513.50 g vs. 3617.79 g). For CPR cut-off point of 1.08: sensitivity was (0.945), specificity 0.1, positive predictive values 0.979, negative predictive values 0.04 and accuracy 0.926. The ROC curves for CPR were: area under the curve was 0.52 at CI 95% (0.342–0.698), p = 0.8271.

Conclusion

Screening in pregnancies with appropriate-for-gestational-age fetuses at 36–42 weeks of gestation using Doppler parameters is not useful in the prediction of adverse perinatal outcomes like an Apgar score < 7 at 1 minute.

Assessment of the Fetal Cerebral Artery: Importance of Doppler Preset Settings

OBJECTIVES

The Doppler assessment of the middle cerebral artery (MCA) has a central role in the monitoring of high-risk pregnancies. The objective of this study was to investigate the importance of Doppler preset settings for measurement of the peak systolic velocity (PSV) and pulsatility index (PI) of the MCA.

METHODS

The PI and PSV of the MCA were determined prospectively in 350 healthy fetuses between 19 and 42 weeks of pregnancy. The first measurement of the MCA (MCA.S) was performed with the conventional settings and the second (MCA.O) with an optimized setting of the maximum achievable frame rate. For the MCA.O measurement, the width of the B-mode image and the color Doppler window were adjusted as narrowly as possible. In addition, the MCA was shown in optimized high-definition zoom. Resulting values were compared with commonly used reference values.

RESULTS

The PSV and PI values and frame rates of the MCA.O setting were noticeably greater than those of the MCA.S setting (P < .001 for all). For both settings, the PSV and PI values were increased compared to common reference values.

CONCLUSIONS

The assessment of the MCA with the optimized Doppler default setting yielded increased PSV and PI values compared to the commonly used measurement technique. Moreover, the resulting median curves differed from the established median reference curves. Therefore, an updated standardization for measuring the MCA should be set out, and current reference values should be adjusted.

Pregnancy-specific stress, fetoplacental haemodynamics, and neonatal outcomes in women with small for gestational age pregnancies: a secondary analysis of the multicentre Prospective Observational Trial to Optimise Paediatric Health in Intrauterine Growth Restriction

OBJECTIVES

To examine associations between maternal pregnancy-specific stress and umbilical (UA PI) and middle cerebral artery pulsatility indices (MCA PI), cerebroplacental ratio, absent end diastolic flow (AEDF), birthweight, prematurity, neonatal intensive care unit admission and adverse obstetric outcomes in women with small for gestational age pregnancies. It was hypothesised that maternal pregnancy-specific stress would be associated with fetoplacental haemodynamics and neonatal outcomes.

DESIGN

This is a secondary analysis of data collected for a large-scale prospective observational study.

SETTING

This study was conducted in the seven major obstetric hospitals in Ireland and Northern Ireland.

PARTICIPANTS

Participants included 331 women who participated in the Prospective Observational Trial to Optimise Paediatric Health in Intrauterine Growth Restriction. Women with singleton pregnancies between 24 and 36 weeks gestation, estimated fetal weight <10th percentile and no major structural or chromosomal abnormalities were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Serial Doppler ultrasound examinations of the umbilical and middle cerebral arteries between 20 and 42 weeks gestation, Pregnancy Distress Questionnaire (PDQ) scores between 23 and 40 weeks gestation and neonatal outcomes.

RESULTS

Concerns about physical symptoms and body image at 35-40 weeks were associated with lower odds of abnormal UAPI (OR 0.826, 95% CI 0.696 to 0.979, p=0.028). PDQ score (OR 1.073, 95% CI 1.012 to 1.137, p=0.017), concerns about birth and the baby (OR 1.143, 95% CI 1.037 to 1.260, p=0.007) and concerns about physical symptoms and body image (OR 1.283, 95% CI 1.070 to 1.538, p=0.007) at 29-34 weeks were associated with higher odds of abnormal MCA PI. Concerns about birth and the baby at 29-34 weeks (OR 1.202, 95% CI 1.018 to 1.421, p=0.030) were associated with higher odds of AEDF. Concerns about physical symptoms and body image at 35-40 weeks were associated with decreased odds of neonatal intensive care unit admission (OR 0.635, 95% CI 0.435 to 0.927, p=0.019).

CONCLUSIONS

These findings suggest that fetoplacental haemodynamics may be a mechanistic link between maternal prenatal stress and fetal and neonatal well-being, but additional research is required.

Is middle cerebral artery Doppler related to neonatal and 2-year infant outcome in early fetal growth restriction?

BACKGROUND

Reduced fetal middle cerebral artery Doppler impedance is associated with hypoxemia in fetal growth restriction. It remains unclear as to whether this finding could be useful in timing delivery, especially in the third trimester. In this regard there is a paucity of evidence from prospective studies.

OBJECTIVES

The aim of this study was to determine whether there is an association between middle cerebral artery Doppler impedance and its ratio with the umbilical artery in relation to neonatal and 2 year infant outcome in early fetal growth restriction (26⁺⁰-31⁺⁶ weeks of gestation). Additionally we sought to explore which ratio is more informative for clinical use.

STUDY DESIGN

This is a secondary analysis from the Trial of Randomized Umbilical and Fetal Flow in Europe, a prospective, multicenter, randomized management study on different antenatal monitoring strategies (ductus venosus Doppler changes and computerized cardiotocography short-term variation) in fetal growth restriction diagnosed between 26⁺⁰ and 31⁺⁶ weeks. We analyzed women with middle cerebral artery Doppler measurement at study entry and within 1 week before delivery and with complete postnatal follow-up (374 of 503). The primary outcome was survival without neurodevelopmental impairment at 2 years corrected for prematurity. Neonatal outcome was defined as survival until first discharge home without severe neonatal morbidity. Z-scores were calculated for middle cerebral artery pulsatility index and both umbilicocerebral and cerebroplacental ratios. Odds ratios of Doppler parameter Z-scores for neonatal and 2 year infant outcome were calculated by multivariable logistic regression analysis adjusted for gestational age and birthweight p50 ratio.

RESULTS

Higher middle cerebral artery pulsatility index at inclusion but not within 1 week before delivery was associated with neonatal survival without severe morbidity (odds ratio, 1.24; 95% confidence interval, 1.02-1.52). Middle cerebral artery pulsatility index Z-score and umbilicocerebral ratio Z-score at inclusion were associated with 2 year survival with normal neurodevelopmental outcome (odds ratio, 1.33; 95% confidence interval, 1.03-1.72, and odds ratio, 0.88; 95% confidence interval, 0.78-0.99, respectively) as were gestation at delivery and birthweight p50 ratio (odds ratio, 1.41; 95% confidence interval, 1.20-1.66, and odds ratio, 1.86; 95% confidence interval, 1.33-2.60, respectively). When comparing cerebroplacental ratio against umbilicocerebral ratio, the incremental range of the cerebroplacental ratio tended toward zero, whereas the umbilicocerebral ratio tended toward infinity as the values became more abnormal.

CONCLUSION

In a monitoring protocol based on ductus venosus and cardiotocography in early fetal growth restriction (26⁺⁰-31⁺⁶ weeks of gestation), the impact of middle cerebral artery Doppler and its ratios on outcome is modest and less marked than birthweight and delivery gestation. It is unlikely that middle cerebral artery Doppler and its ratios are informative in optimizing the timing of delivery in fetal growth restriction before 32 weeks of gestation. The umbilicocerebral ratio allows for a better differentiation in the abnormal range than the cerebroplacental ratio.

Biophysical and biochemical markers at 30-34 weeks' gestation in the prediction of adverse perinatal outcome

OBJECTIVE

To investigate the potential value of biophysical and biochemical markers at 30-34 weeks' gestation in the prediction of adverse perinatal outcome.

METHODS

This was a screening study in 8268 singleton pregnancies at 30-34 weeks' gestation. Estimated fetal weight (EFW), uterine artery (UtA) pulsatility index (PI), umbilical artery (UA) PI, fetal middle cerebral artery (MCA) PI, mean arterial pressure (MAP), serum placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) were measured. The detection rate (DR) and false-positive rate (FPR) of screening by each biomarker were estimated for stillbirth, pre-eclampsia, delivery of small-for-gestational-age (SGA) neonate, Cesarean section for fetal distress before or during labor, umbilical arterial cord blood pH ≤7.0 or umbilical venous cord blood pH ≤7.1, 5-min Apgar score < 7 and admission to the neonatal unit (NNU).

RESULTS

Multivariable regression analysis demonstrated that significant prediction of PE was provided by PlGF, sFlt-1, MAP and MCA-PI, with a DR of 98% for PE delivering < 37 weeks' gestation and 56% for those delivering ≥ 37 weeks, at a 10% FPR. Prediction of SGA was provided by EFW, PlGF, sFlt-1, UtA-PI, UA-PI and MCA-PI, with a DR of 88% for SGA delivering < 37 and 51% for those delivering ≥ 37 weeks' gestation, at a 10% FPR. Prediction of stillbirth was provided by EFW, UtA-PI and MCA-PI, with DR of 30% at 10% FPR. Prediction of Cesarean section for fetal distress before labor was provided by EFW, sFlt-1, UtA-PI and UA-PI, with a DR of 90% at a 10% FPR. Prediction of fetal distress in labor was provided by EFW and sFlt-1, with a DR of 16% at a 10% FPR. There were no significant differences from the normal outcome group in any of the biomarkers for low cord blood pH, low Apgar score or NNU admission for cases other than those with PE and/or SGA.

CONCLUSION

At 30-34 weeks' gestation, biomarkers of impaired placentation and fetal hypoxemia provide good prediction of PE, SGA and fetal distress before labor, but poor or no prediction of stillbirth and adverse events in labor or after birth.

Umbilical and fetal middle cerebral artery Doppler at 35-37 weeks' gestation in the prediction of adverse perinatal outcome

OBJECTIVE

To investigate the potential value of cerebroplacental ratio (CPR) at 36 weeks' gestation in the prediction of adverse perinatal outcome.

METHODS

This was a screening study in 6178 singleton pregnancies at 35-37 weeks' gestation. Umbilical artery (UA) and fetal middle cerebral artery (MCA) pulsatility index (PI) were measured and the values were converted to multiples of the median (MoM) after adjustment from variables in maternal characteristics and medical history that affect the measurements. CPR was calculated by dividing MCA-PI MoM by UA-PI MoM. Multivariable logistic regression analysis was used to determine if measuring CPR improved the prediction of adverse perinatal outcome provided by maternal characteristics, medical history and obstetric factors. The detection rate (DR) and false-positive rate (FPR) of screening by CPR were estimated for stillbirth, Cesarean section for fetal distress, umbilical arterial cord blood pH ≤ 7.0, umbilical venous cord blood pH ≤ 7.1, 5-min Apgar score < 7 and admission to the neonatal unit (NNU) and neonatal intensive care unit (NICU).

RESULTS

There was a linear association between CPR and both birth-weight Z-score and arterial or venous umbilical cord blood pH, but the steepness of the regression lines was inversely related to the interval from assessment to delivery. The performance of low CPR < 5(th) percentile in screening for each adverse outcome was poor, with DRs of 6-15% and a FPR of about 6%. In the small subgroup of the population delivering within 2 weeks of assessment, the DRs improved to 14-50%, but with a simultaneous increase in FPR, to about 10%.

CONCLUSION

The performance of CPR in routine screening for adverse perinatal outcome at 36 weeks' gestation is poor.

Umbilical and fetal middle cerebral artery Doppler at 30-34 weeks' gestation in the prediction of adverse perinatal outcome

OBJECTIVE

To investigate the potential value of cerebroplacental ratio (CPR) at 30-34 weeks' gestation in the prediction of adverse perinatal outcome.

METHODS

This was a screening study in 30 780 singleton pregnancies at 30-34 weeks' gestation. Umbilical artery (UA) and fetal middle cerebral artery (MCA) pulsatility index (PI) were measured and the values were converted to multiples of the median (MoM) after adjustment from variables in maternal characteristics and medical history that affect the measurements. CPR was calculated by dividing MCA-PI MoM by UA-PI MoM. Multivariable logistic regression analysis was used to determine if measuring CPR improved the prediction of adverse perinatal outcome provided by screening with maternal characteristics, medical history and obstetric factors. The detection rate (DR) and false-positive rate (FPR) of screening by CPR were estimated for stillbirth, Cesarean section for fetal distress, umbilical arterial cord blood pH ≤ 7.0, umbilical venous cord blood pH ≤ 7.1, 5-min Apgar score < 7 and admission to the neonatal unit (NNU) and neonatal intensive care unit (NICU).

RESULTS

There was a significant association between CPR and birth-weight Z-score. In addition to maternal characteristics, medical history and obstetric factors, measuring CPR provided a significant contribution to the prediction of arterial cord blood pH ≤ 7.0, venous cord blood pH ≤ 7.1 and admission to NNU. The performance of CPR in screening for each adverse outcome was poor, with DR of 5-11% and a FPR of about 5%. In the small subgroup of the population delivering within 2 weeks following assessment, the DR improved to 20-50%, but with a simultaneous increase in FPR to 10-23%.

CONCLUSION

The performance of CPR in routine screening for adverse perinatal outcome at 30-34 weeks' gestation is poor.