Fetal arterial and venous Doppler pulsatility index and time averaged velocity ranges

Umbilical artery half peak systolic velocity deceleration time: a novel Doppler parameter for prediction of neonatal outcomes in pregnant women with preeclampsia

PURPOSE

To assess the effectiveness of half peak systolic velocity deceleration time (hPSV-DT) in predicting neonatal outcomes in pregnant women with preeclampsia and to compare its usefulness with the conventional umbilical artery (UA) pulsatility index (PI) approach.

METHODS

A prospective cohort study was conducted among pregnant women with preeclampsia who were admitted to the Department of Perinatology, Ministry of Health Ankara City Hospital between 01 September 2022 and 01 January 2023 at 28-41 weeks gestational age. 55 patients were divided into two groups: the study group with UA hPSV-DT value < 5th percentile (n = 22) and the control group with UA hPSV-DT value ≥ 5th percentile (n = 33). UA hPSV-DT calculates the time in milliseconds needed to halve the maximal velocity of the UA waveform using Doppler ultrasonography.

RESULTS

Birth weight, gestational age at birth, 1st minute APGAR, 5th minute APGAR, and umbilical cord pH values were significantly lower in the anormal hPSV-DT group (p < 0.05). Additionally, the rates of admission to NICU, respiratory distress syndrome (RDS), delivery time < 34 weeks, and birth weight < 2500 g were significantly more frequent in the anormal hPSV-DT group compared to the normal hPSV-DT group (p < 0.05). UA-PI > 95th percentile was detected in only 2 (8%) of 23 patients whose newborns were admitted to the NICU (p = 0.149), while hPSV-DT < 5th percentile was detected in 16 (69%) of 23 patients (p < 0.001). According to ROC analysis, the area under the curve was 0.82 (95% CI 0.06-0.28) for admission to the NICU. The best balance of sensitivity/specificity in ROC curves was 221.5 (82.6% sensitivity, 69.1% specificity, p < 0.001).

CONCLUSION

UA hPSV-DT was successful in predicting composite adverse perinatal outcomes in pregnant women with preeclampsia. It is a promising novel method that is accurate, quantitative, reproducible, and easily applicable. With further studies, this method may be a primary diagnostic tool in the management of high-risk pregnancies and in determining the optimal timing of delivery.

Continuous non-invasive measurement of cardiac output in neonatal intensive care using regional impedance cardiography: a prospective observational study

OBJECTIVES

To compare agreement between echocardiography and regional impedance cardiography (RIC)-derived cardiac output (CO), and to construct indicative normative ranges of CO for gestational age groups.

DESIGN, SETTING AND PARTICIPANTS

Prospective cohort observational study performed in a tertiary centre in London, UK, including neonates born between 25 and 42 weeks' gestational age.

EXPOSURES

Neonates on the postnatal ward had 2 hours of RIC monitoring; neonates in intensive care had RIC monitoring for the first 72 hours, then weekly for 2 hours, with concomitant echocardiography measures.

MAIN OUTCOMES AND MEASURES

RIC was used to measure CO continuously. Statistical analyses were performed using R (V.4.2.2; R Core Team 2022). RIC-derived CO and echocardiography-derived CO were compared using Pearson's correlations and Bland-Altman analyses. Differences in RIC-derived CO between infants born extremely, very and late preterm were assessed using analyses of variance and mixed-effects modelling.

RESULTS

127 neonates (22 extremely, 46 very, 29 late preterm and 30 term) were included. RIC and echocardiography-measured weight-adjusted CO were correlated (r=0.62, p<0.001) with a Bland-Altman bias of -31 mL/min/kg (limits of agreement -322 to 261 mL/min/kg). The RIC-derived CO fell over 12 hours, then increased until 72 hours after birth. The 72-hour weight-adjusted mean CO was higher in extremely preterm (424±158 mL/min/kg) compared with very (325±131 mL/min/kg, p<0.001) and late preterm (237±81 mL/min/kg, p<0.001) neonates; this difference disappeared by 2-3 weeks of age.

CONCLUSIONS

RIC is valid for continuous, non-invasive CO measurement in neonates. Indicative normative CO ranges could help clinicians to make more informed haemodynamic management decisions, which should be explored in future studies.

TRIAL REGISTRATION NUMBER

NCT04064177.

Assessment of the cerebroplacental ratio and uterine arteries in low-risk pregnancies in early labour for the prediction of obstetric and neonatal outcomes

BACKGROUND

The evidence-based management of human labor includes the antepartum identification of patients at risk for intrapartum hypoxia. However, available evidence has shown that most of the hypoxic-related complications occur among pregnancies classified at low-risk for intrapartum hypoxia, thus suggesting that the current strategy to identify the pregnancies at risk for intrapartum fetal hypoxia has limited accuracy.

OBJECTIVE

To evaluate the role of the combined assessment of the cerebroplacental ratio (CPR) and uterine arteries (UtA) Doppler in the prediction of obstetric intervention (OI) for suspected intrapartum fetal compromise (IFC) within a cohort of low-risk singleton term pregnancies in early labor.

METHODS

Prospective multicentre observational study conducted across four tertiary Maternity Units between January 2016 and September 2019. Low-risk term pregnancies with spontaneous onset of labor were included. A two-step multivariable model was developed to assess the risk of OI for suspected IFC. The baseline model included antenatal and intrapartum characteristics, while the combined model included antenatal and intrapartum characteristics plus Doppler anomalies such as CPR MoM < 10th percentile and mean UtA Doppler PI MoM ≥ 95th percentile. Predictive performance was determined by receiver-operating characteristics curve analysis.

RESULTS

804 women were included. At logistic regression analysis, CPR MoM < 10th percentile (aOR 1.269, 95 % CI 1.188-1.356, P < 0.001), mean UtA PI MoM ≥ 95th percentile (aOR 1.012, 95 % CI 1.001-1.022, P = 0.04) were independently associated with OI for suspected IFC. At ROC curve analysis, the combined model including antenatal characteristics plus abnormal CPR and mean UtA PI yielded an AUC of 0.78, 95 %CI(0.71-0.85), p < 0.001, which was significantly higher than the baseline model (AUC 0.61, 95 %CI(0.54-0.69), p = 0.007) (p < 0.001). The combined model was associated with a 0.78 (95 % CI 0.67-0.89) sensitivity, 0.68 (95 % CI 0.65-0.72) specificity, 0.15 (95 % CI 0.11-0.19) PPV, and 0.98 (0.96-0.99) NPV, 2.48 (95 % CI 2.07-2.97) LR + and 0.32 (95 % CI 0.19-0.53) LR- for OI due to suspected IFC.

CONCLUSIONS

A predictive model including antenatal and intrapartum characteristics combined with abnormal CPR and mean UtA PI has a good capacity to rule out and a moderate capacity to rule in OI due to IFC, albeit with poor predictive value.

A longitudinal and cross-sectional study of placental circulation between normal and placental insufficiency pregnancies

INTRODUCTION

To longitudinally and cross-sectionally study the differences in the uterine artery pulsatility index (UTPI), umbilical artery pulsatility index (UAPI) and placental vascularization indices (PVIs, derived from 3-dimensional power Doppler) between normal and placental insufficiency pregnancies throughout gestation.

METHODS

UTPI, UAPI and PVI were measured 6 times at 4- to 5- week intervals from 11 to 13+6 weeks-36 weeks. Preeclampsia (PE) and fetal growth restriction (FGR) were defined as placental insufficiency. Comparisons of UTPI, UAPI and PVI between normal and insufficiency groups were performed by one-way repeated measures analysis of variance.

RESULTS

A total of 125 women were included: monitored regularly from the first trimester to 36 weeks of gestation: 109 with normal pregnancies and 16 with placental insufficiency. Longitudinal study of the normal pregnancy group showed that UTPI and UAPI decreased significantly every 4 weeks, while PVIs increased significantly every 8 weeks until term. In the placental insufficiency group however, this decrease occurred slower at 8 weeks intervals and UTPI stabilized after 24 weeks. No significant difference was noted in PVIs throughout pregnancy. Cross-sectional study from different stages of gestation showed that UTPI was higher in the insufficiency group from 15 weeks onward and PVIs were lower after 32 weeks.

DISCUSSION

Compared to high-risk pregnancies with normal outcome, UTPI and UAPI needed a longer time to reach a significant change in those with clinical confirmation of placental insufficiency pregnancies and no significant change was found in PVI throughout gestation. UTPI was the earliest factor in detecting adverse outcome pregnancies.

Early-onset fetal growth restriction: comparison of two management protocols in a single tertiary center

OBJECTIVE

Compare the neonatal outcomes of two protocols of diagnosis and surveillance of pregnancies complicated by early-onset FGR in a tertiary hospital.

METHODS

This is a retrospective cohort study of pregnant women diagnosed with early-onset FGR between 2017 and 2020. We compared the obstetric and perinatal outcomes between two different management protocols (before and after 2019).

RESULTS

Seventy-two cases of early-onset FGR were diagnosed in the forementioned period: 45 (62.5%) were managed according to protocol 1 and 27 (37.5%) according to protocol 2. Mean gestational age at delivery was significantly different between groups: 34.9 ± 3.1 weeks (95% CI 34.0-35.9) in group 1 and 32.3 ± 4.4 weeks (95% CI 30.4-33.9) in group 2. 74.1% (20) of newborns in group 2 were admitted in de NICU, a significant difference when compared with 46.7% of group 1. There were no statistically significant differences in the remaining serious neonatal adverse outcomes.

CONCLUSIONS

This is the first study published comparing two different protocols of management of FGR. The implementation of the new protocol seems to have led to a decrease in the number of fetuses labeled as growth restricted and to a decrease in the gestational age of delivery of such fetuses, but without increasing the rate of serious neonatal adverse outcomes.

SYNOPSIS

The implementation of the 2016 ISUOG guidelines for the diagnosis of fetal growth restriction seems to have led to a decrease in the number of fetuses labeled as growth restricted and to a decrease in the gestational age of delivery of such fetuses, but without increasing the rate of serious neonatal adverse outcomes.

Developmental Ultrasound Characteristics in Guinea Pigs: Similarities with Human Pregnancy

BACKGROUND

Biometrical and blood flow examinations are fundamental for assessing fetoplacental development during pregnancy. Guinea pigs have been proposed as a good model to study fetal development and related gestational complications; however, longitudinal growth and blood flow changes in utero have not been properly described. This study aimed to describe fetal and placental growth and blood flow of the main intrauterine vascular beds across normal guinea pig pregnancy and to discuss the relevance of this data for human pregnancy.

METHODS

Pregnant guinea pigs were studied from day 25 of pregnancy until term (day ~70) by ultrasound and Doppler assessment. The results were compared to human data from the literature.

RESULTS

Measurements of biparietal diameter (BPD), cranial circumference (CC), abdominal circumference, and placental biometry, as well as pulsatility index determination of umbilical artery, middle cerebral artery (MCA), and cerebroplacental ratio (CPR), were feasible to determine across pregnancy, and they could be adjusted to linear or nonlinear functions. In addition, several of these parameters showed a high correlation coefficient and could be used to assess gestational age in guinea pigs. We further compared these data to ultrasound variables from human pregnancy with high similarities.

CONCLUSIONS

BPD and CC are the most reliable measurements to assess fetal growth in guinea pigs. Furthermore, this is the first report in which the MCA pulsatility index and CPR are described across guinea pig gestation. The guinea pig is a valuable model to assess fetal growth and blood flow distribution, variables that are comparable with human pregnancy.

Maternal Steroids on Fetal Doppler Indices, in Growth-Restricted Fetuses with Abnormal Umbilical Flow from Pregnancies Complicated with Early-Onset Severe Preeclampsia

Corticoids are largely used for fetal interest in expected preterm deliveries. This study went further, evaluating the effect of maternal administration of dexamethasone (Dex) on the umbilical artery (UA), middle cerebral artery (MCA), and ductus venous (DV) spectrum, in growth-restricted fetuses, with the absent end-diastolic flow (AEDF) in UA, from singleton early-onset severe preeclamptic pregnancies. Supplementary, the impact on both uterine arteries (UTAs) flow was also evaluated. In 68.7% of cases, the EDF was transiently restored (trAEDF group), in the rest of 31.2% remained persistent absent (prAEDF group). UA-PI significantly decreased in the first day after Dex (day 1/0; p < 0.05), reaching its minimum during day 2 (day 2/1; p > 0.05), revealing a significant recovery to day 4 (day 4/2; p < 0.05), in both groups. The MCA-PI decreased from day 1 until day 3 in both groups, but significantly only in the trAEDF group (p = 0.030 vs. p = 0.227. The DV-PI's decrease (during day 1) and the CPR's increase (between days 0 and 2) were not significant in both groups. UTAs-PIs did not vary. The prAEDF group had a significantly increased rate of antenatal worsening Doppler and a poorer perinatal outcome compared with the trAEDF group. In conclusion, Dex transiently restored the AEDF in UA in the majority of cases, a "positive" effect being a useful marker for better perinatal prognosis. UA-PI significantly decreased in all cases. The improvement in umbilical circulation probably was responsible for the short but not significant DV-PI reduction. MCA-PI decreased only in sensitive cases, probably due to an already cerebral "full" vasodilation in the prAEDF group. Furthermore, the CPR's nonsignificant improvement was the result of a stronger effect of Dex on UA-PI than on MCA-PI. Finally, despite the same etiology, it was only a weak correlation between the severity of the umbilical and uterine abnormal spectrum.

T2* weighted fetal MRI and the correlation with placental dysfunction

INTRODUCTION

Transverse relaxation time (T2*) is related to tissue oxygenation and morphology. We aimed to describe T2* weighted MRI in selected fetal organs in normal pregnancies, and to investigate the correlation between fetal organ T2* and placental T2*, birthweight (BW) deviation, and redistribution of fetal blood flow.

METHODS

T2*-weighted MRI was performed in 126 singleton pregnancies between 23+6- and 41+3-weeks' gestation. The T2* value was obtained from the placenta and fetal organs (brain, lungs, heart, liver, kidneys, and spleen). In normal BW pregnancies (BW > 10th centile), the correlation between the T2* value and gestational age (GA) at MRI was estimated by linear regression. The correlation between fetal organ Z-score and BW group was demonstrated by boxplots and investigated by analysis of variance (ANOVA) for each organ.

RESULTS

In normal BW pregnancies fetal organ T2* was negatively correlated with GA. We found a significant correlation between BW group and fetal organ T2* z-score in the fetal heart, kidney, lung and spleen. A positive linear correlation was demonstrated between fetal organ T2* and outcomes related to placental function such as BW deviation and placenta T2* in all investigated fetal organs except for the fetal liver. In the fetal heart, kidneys, and spleen the T2* value showed a significant correlation with fetal redistribution of blood flow (Middle cerebral artery Pulsatility Index) before delivery.

DISCUSSION

Fetal T2* is correlated with BW, placental function, and redistribution of fetal blood flow, suggesting that fetal organ T2* reflects fetal oxygenation and morphological changes related to placental dysfunction.

Burst Spinal Cord Stimulation in Pregnancy: First Clinical Experiences

OBJECTIVES

Spinal cord stimulation (SCS) is a treatment for chronic neuropathic pain. It is based on the delivery of electric impulses to the spinal cord, traditionally in a regular square-wave pattern ("tonic" stimulation) and, more recently, in a rhythmic train-of-five "BurstDR" pattern. The safety of active SCS therapy in pregnancy is not established, and recommendations are based on limited casuistic evidence. We present in this study clinical data on a case series of six women treated with burst SCS during pregnancy. In addition, we present the ultrasonographic flow measurements of fetal and uteroplacental blood flow in a pregnant patient.

MATERIALS AND METHODS

Patients were included if they had been implanted with a full SCS system at Aarhus University Hospital, Denmark, between 2006 and 2020 and received active burst SCS stimulation during a pregnancy. Telephone interviews were conducted, including details on SCS therapy, medication, pregnancy course and outcome, and health status of the offspring. In one patient, the uteroplacental and fetal blood flow was assessed in gestational week 29 by Doppler flow measurements performed during both ON and OFF phases of the SCS system.

RESULTS

Six patients were included with a total of 11 pregnancies. Three pregnancies ended in miscarriages, all in the same patient who had preexisting significant risk factors for miscarriage. Eight resulted in a live-born child with normal birth weight for gestational age; seven were born at term, and one was born late preterm, in gestational week 36. Ultrasonographic Doppler flow, measured in one patient, was normal and did not reveal any immediate changes between burst SCS ON and OFF. Seven children were reported healthy with normal neurodevelopment and one physically healthy but with developmental delays.

CONCLUSIONS

The data presented in this study add to the accumulating evidence of the safety of SCS in pregnancy.

Longitudinal changes in fetal head biometry and fetoplacental circulation in fetuses with congenital heart defects

INTRODUCTION

Objectives were to analyze changes in fetal cephalic biometry and fetoplacental circulation throughout pregnancy in fetuses with congenital heart defects.

MATERIAL AND METHODS

Prospective study conducted on three university tertiary referral hospitals. Fetuses with the diagnosis of isolated congenital heart defects attending between 2014 and 2018 were included. Congenital heart defects were divided into two groups according to the oxygen supply to the central nervous system: group I (expected low placental blood content and low oxygen delivery to the brain) and group II (expected intermediate and high placental blood content). Fetal biometry and Doppler parameters were collected between 25-30 weeks of gestation and 34-40 weeks of gestation and transformed into Z scores. The results were compared with healthy controls. Finally, general linear modeling was performed to analyze repeated measurements.

RESULTS

In all, 71 fetuses met the inclusion criteria. Fetuses with congenital heart defects had significantly smaller head (biparietal diameter [p < 0.001], head circumference [p = 0.001]) and abdominal circumference (p < 0.001), and lower estimated fetal weight (p < 0.001) than controls. When analyzing according to congenital heart defects type, head size was significantly smaller in group I compared with group II (p = 0.04). Regarding Doppler parameters, fetuses with congenital heart defects showed higher umbilical artery pulsatility index (p < 0.001) and lower cerebroplacental ratio (p = 0.044) than controls. In group I, umbilical artery pulsatility index was above the 95th centile in 15.4% of fetuses compared with 6.7% in group II and 1.9% in controls (p < 0.001); moreover, middle cerebral artery pulsatility index was below the 5th centile in 5.4% of group I fetuses compared with 0% in group II and 1.2% in controls (p = 0.011). General linear model for two measurements showed significant longitudinal changes in biometric parameters. Growth rate of fetal head through pregnancy (head circumference Z score) was lower in fetuses with congenital heart defects compared with controls (p = 0.043). In group I, the head circumference Z score longitudinal decrease was significantly higher than in group II (p < 0.001).

CONCLUSIONS

Fetuses with congenital heart defects are at risk of smaller head size and Doppler changes. Growth rate of fetal head throughout pregnancy is also affected. These findings are mainly associated with cardiac defects with expected low oxygen supply to the central nervous system.

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.

The impact of anti-hypertensive treatment on foetal growth and haemodynamics in pregnant women with pre-existing diabetes - An explorative study

OBJECTIVES

To explore the impact of anti-hypertensive treatment of pregnancy-induced hypertension on foetal growth and hemodynamics in women with pre-existing diabetes.

METHODS

A prospective cohort study of 247 consecutive pregnant women with pre-existing diabetes (152 type 1 diabetes; 95 type 2 diabetes), where tight anti-hypertensive treatment was initiated and intensified (mainly with methyldopa) when office blood pressure (BP) ≥135/85 mmHg and home BP ≥130/80 mmHg. Foetal growth was assessed by ultrasound at 27, 33 and 36 weeks and foetal hemodynamics were assessed by ultrasound Doppler before and 1-2 weeks after initiation of anti-hypertensive treatment.

RESULTS

In 215 initially normotensive women, anti-hypertensive treatment for pregnancy-induced hypertensive disorders was initiated in 42 (20%), whilst 173 were left untreated. Chronic hypertension was present in 32 (13%). Anti-hypertensive treatment for pregnancy-induced hypertensive disorders was not associated with foetal growth deviation (linear mixed model, p = 0.681). At 27 weeks, mainly before initiation of anti-hypertensive treatment, the prevalence of small foetuses with an estimated foetal weight <10th percentile was 12% in women initiating anti-hypertensive treatment compared with 4% in untreated women (p = 0.054). These numbers were close to the prevalence of birth weight ≤10th percentile (small for gestational age (SGA)) (17% vs. 4%, p = 0.003). Pulsatility index in the umbilical and middle cerebral artery remained stable after the onset of anti-hypertensive treatment in a representative subgroup (n = 12, p = 0.941 and p = 0.799, respectively).

CONCLUSION

There is no clear indication that antihypertensive treatment causes harm in this particular at-high-risk group of pregnant women with diabetes, such that a larger well-designed study to determine the value of tight antihypertensive control would be worthwhile.

The aorto-left ventricular tunnel from a fetal perspective: original case series and literature review

Introduction

Aorto‐left ventricular tunnel (ALVT) accounts for <0.1% of congenital heart defects. Evidence on the prognosis from a fetal perspective is limited. With this retrospective international case series, we provide information on the outcome of fetuses with ALVT.

Methods

All members of the Association for European Pediatric and Congenital Cardiology's (AEPC) fetal working group and fetal medicine units worldwide were invited for participation. We observed antenatal parameters, neonatal outcome and postnatal follow‐up. Additionally, a systematic search of the literature was performed.

Results

Twenty fetuses with ALVT were identified in 10 participating centers (2001–2019). Fetal echocardiographic characteristics of ALVT included an increased cardiac–thorax ratio (95%), left ventricular end‐diastolic diameter (90%) and a dysplastic aortic valve (90%). Extracardiac malformations were rare (5%). Eight fetuses died at a median gestational age (GA) of 21 + 6 weeks (range, 19–24): all showed signs of hydrops prior to 24 weeks or at autopsy. All others (60%, 12/2) were live–born (median GA 38 + 4, range 37–40), underwent surgery and were alive at last follow up (median 3.2 years, range 0.1–17). The literature reported 22 ALVT fetuses with similar outcome.

Conclusions

In the absence of fetal hydrops, ALVT carries a good prognosis. Fetuses who survive to 24 weeks without hydrops are likely to have a good outcome.

What's already known about this topic?

Aorto‐left ventricular tunnel (ALVT) is an extremely rare diagnosis that may cause congenital heart failure and fetal hydrops, leading to fetal or neonatal death.

A few case reports show that after corrective surgery in the neonatal period, cases with ALVT tend to have a good prognosis.

What does this study add?

This is the first study that evaluates prenatal characteristics, prognostic parameters and outcome following a prenatal diagnosis of ALVT in a cohort of cases worldwide, including a systematic review of the literature as well.

In the absence of fetal hydrops, ALVT carries a good prognosis. Fetuses who survive to 24 weeks without hydrops are likely to have a good outcome.

Diagnostic accuracy of Kleihauer-Betke (Kb) testing to predict fetal outcomes associated with fetomaternal hemorrhage: a retrospective cohort study

OBJECTIVE

To evaluate the diagnostic and screening utility of Kleihauer-Betke (KB) testing as a triage tool in predicting adverse fetal outcomes associated with fetomaternal hemorrhage (FMH).

STUDY DESIGN

Single center retrospective cohort study evaluated a primary composite outcome of fetal complications associated with FMH between KB-negative and KB-positive test groups. Screening tests for sensitivity, specificity, positive predictive value and negative predictive value were determined.

RESULTS

641 women (97%) had KB-negative and 22 (3%) had KB-positive tests. The primary composite outcome between KB-negative and KB-positive pregnancies was similar (30% vs. 36%, p = 0.54). Screening exhibited high specificity (97%), however, test sensitivity was poor (4%) with only moderate positive and negative predictive values (36.4 and 69.7%).

CONCLUSION

Fetal outcomes associated with FMH were not significantly different between KB-positive and KB-negative test cohorts; KB testing offers no diagnostic precision in the emergency triage evaluation of women with suspected FMH.

A survey of current practice in reporting third trimester fetal biometry and Doppler in Australia and New Zealand

Introduction

Inconsistent reporting practices in third trimester ultrasound, the choice of reference charts in particular, have the potential to misdiagnose abnormal fetal growth. But this may lead to unnecessary anxiety and confusion amongst patients and clinicians and ultimately influence clinical management. Therefore, we sought to determine the extent of variability in choice of fetal biometry and Doppler reference charts and reporting practices in Australia and New Zealand.

Methods

Clinicians performing and/or reporting obstetric ultrasound were invited to answer questions about fetal biometry and Doppler charts in a web-based survey.

Results

At least four population-based charts are in current use. The majority of respondents (78%) report the percentile for known gestational age (GA) alongside measurements and 63% using a cut-off of estimated fetal weight (EFW) < 10^th percentile when reporting small for gestational age (SGA) and/or fetal growth restriction (FGR). The thresholds for the use of fetal and maternal Doppler in third trimester ultrasound varied in terms of the GA, EFW cut-off, and how measures were reported. The majority of respondents were not sure of which Doppler charts were used in their practice.

Conclusion

This survey revealed inconsistencies in choice of reference chart and reporting practices. The potential for misdiagnosis of abnormal fetal growth remains a significant issue.

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

Background

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

Methods

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

Results

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

Conclusions

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

Supplementary Information

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

Are single nucleotide polymorphisms rs7903146 and rs12255372 in transcription factor 7-like 2 gene associated with an increased risk for gestational diabetes mellitus in Egyptian women?

BACKGROUND

Genetic variants in the transcription factor 7-like 2 (TCF7L2) gene are related with type 2 diabetes (T2D) and gestational diabetes mellitus (GDM) in various populations, but there are not enough statistics regarding GDM among Egyptian women. We aimed by this study to evaluate the effect of two polymorphisms of rs7903146 and rs12255372 in the TCF7L2 gene with the development of GDM among Egyptian women.

RESULTS

We enrolled 114 pregnant women with normal glucose tolerance and 114 with GDM according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) guidelines. We gathered records on blood pressure, body mass index (BMI), blood glucose level, hemoglobin A1C (HbA1c), and lipid profile. The genotyping of rs7903146 and rs12255372 polymorphisms was carried out using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The statistical significance of prepregnancy BMI, fasting blood sugar (FBS), HbA1c, low-density lipoprotein (LDL), and total cholesterol (Tch) was higher, P < 0.001, in GDM women in comparison to pregnant women without GDM. CT and TT genotypes in rs7903146 SNP were 46.5% vs. 54%, P <0.04, OR; CI = 1.9 (1.0 to 3.78); TT carriers were 37.7% vs. 9.6%, P <0.001, OR (CI) = 8.9 (3.7-21.1), respectively. For the TCFL2 gene rs12255372 SNP, GT carriers were 48.2% vs. 39.5%, P= 0.004, OR (CI) = 2.3 (1.3-4.2), while TT carriers were 24.6% vs. 7.9%, P < 0.001, OR (CI) = 6 (2.5-14.3).

CONCLUSION

The study showed there is a significantly higher incidence of CT/TT genotypes in rs7903146 SNP and GT/TT genotypes in rs12255372 SNP in TCF7L2 gene among GDM women in comparison to healthy pregnant women (controls).

Placental MRI: Longitudinal relaxation time (T1) in appropriate and small for gestational age pregnancies

OBJECTIVE

The antenatal detection of small for gestational age (SGA) pregnancies is a challenge, which may be improved by placental MRI. The longitudinal relaxation time (T1) is a tissue constant related to tissue morphology and tissue oxygenation, thereby placental T1 may be related to placental function. The aim of this study is to investigate placental T1 in appropriate for gestational age (AGA) and SGA pregnancies.

METHODS

A total of 132 singleton pregnancies were retrieved from our MRI research database. MRI and ultrasound estimated fetal weight (EFW) was performed at gestational week 20.6-41.7 in a 1.5 T system. SGA was defined as BW ≤ -15% of the expected for gestational age (≤10th centile). A subgroup of SGA pregnancies underwent postnatal placental histological examination (PHE) and abnormal PHE was defined as vascular malperfusion. The placental T1 values were converted into Z-scores adjusted for gestational age at MRI. The predictive performance of placental T1 and EFW was compared by receiver operating curves (ROC).

RESULTS

In AGA pregnancies, placental T1 showed a negative linear correlation with gestational age (r = -0.36, p = 0.004) Placental T1 was significantly reduced in SGA pregnancies (mean Z-score = -0.34) when compared to AGA pregnancies, p = 0.03. Among SGA pregnancies placental T1 was not reduced in cases with abnormal PHE, p = 0.84. The predictive performance of EFW (AUC = 0.84, 95% CI, 0.77-0.91) was significantly stronger than placental T1 (AUC = 0.62, 95% CI, 0.52-0.72) (p = 0.002).

DISCUSSION

A low placental T1 relaxation time is associated with SGA at birth. However, the predictive performance of placental T1 is not as strong as EFW.

Biosensor for Detecting Fetal Growth Restriction in a Low-Resource Setting

One strategy for improving detection of fetal growth restriction (FGR) is developing biosensors identifying placental dysfunction as a leading pathogenesis for FGR. The aim of this pilot study was to investigate the performance of a biosensor specified to detect placental dysfunction by means of maternal arterial turbulence acoustics in a low-resource setting. A cohort of 147 singleton pregnant women were prospectively followed with double-blinded biosensor tests, sonographic estimation of fetal weight (EFW) and Doppler flow at 26–28, 32–34 and 37–39 weeks of pregnancy. Full term live births with recorded birth weights (BWs) and without major congenital malformations were included. Outcomes were defined as (A) a solitary biometric measure (BW < 3rd centile) and as (B) a biometric measure and contributory functional measure (BW < 10th centile and antenatally detected umbilical artery pulsatility index > 95th centile). Data from 118 women and 262 antenatal examinations were included. Mean length of pregnancy was 40 weeks (SD ± 8 days), mean BW was 3008 g (SD ± 410 g). Outcome (A) was identified in seven (6%) pregnancies, whereas outcome (B) was identified in one (0.8%) pregnancy. The biosensor tested positive in five (4%) pregnancies. The predictive performance for outcome (A) was sensitivity = 0.29, specificity = 0.97, p = 0.02, positive predictive value (PPV) was 0.40 and negative predictive value (NPV) was 0.96. The predictive performance was higher for outcome (B) with sensitivity = 1.00, specificity = 0.97, p = 0.04, PPV = 0.20 and NPV = 1.00. Conclusively, these pilot-study results show future potential for biosensors as screening modality for FGR in a low-resource setting.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Increased pulsatility index of uterine artery Doppler between 26 and 28 weeks of gestation and adverse perinatal outcomes

OBJECTIVE

To compare adverse perinatal outcomes in pregnant women with or without normalization of the mean pulsatility index (PI) uterine artery Doppler between 24 and 28 weeks of gestation.

METHODS

Retrospective cohort which pregnant women were divided into three groups: normal uterine artery Doppler between 20-24 and 26-28 weeks (controls), abnormal uterine artery Doppler between 20-24 and normal between 26-28 weeks (anUtA), and abnormal uterine artery Doppler between 20-24 and 26-28 weeks (aaUtA). To compare adverse perinatal results between the groups Chi-square test was used. Binary logistic regression was used to assess the ability of uterine artery Doppler to predict birthweight < 10th and composite perinatal outcomes.

RESULTS

Birthweight was significantly lower in the aaUtA compared to anUtA (2687 vs 3248 grams, p = 0.0479). A significant negative correlation was observed between the mean PI uterine artery Doppler during the 3rd trimester and birthweight (r = -0.13, R ² = 0.035, p = .0192). The prevalence of composite perinatal outcomes was significantly higher in aaUtA compared to anUtA (25.9 vs 0%, p = .013). Mean PI uterine artery Doppler during the 3rd trimester was significant predictor for birthweight < 10th (OR: 2.74, CI 95% = 1.03-7.3), but the protodiastolic notch and the association between mean PI uterine artery Doppler and protodiastolic notch were not.

CONCLUSION

Maintenance of altered uterine artery Doppler during the 3rd trimester was associated with higher prevalence of composite perinatal outcomes and lower birthweight compared to its late normalization. Although modest, uterine artery Doppler in the 3rd trimester proved to be predictor of birthweight < 10th.

Hemodynamic findings in normotensive women with small-for-gestational-age and growth-restricted fetuses

INTRODUCTION

Fetal growth restriction (FGR) in most instances is a consequence of primary placental dysfunction due to inadequate trophoblastic invasion. Maternal cardiac maladaptation to pregnancy has been proposed as a possible determinant of placental insufficiency and impaired fetal growth. This study aimed to compare the maternal hemodynamic parameters between normotensive women with small-for-gestational-age (SGA) and FGR fetuses and to evaluate their correlation with neonatal outcome.

MATERIAL AND METHODS

An observational cohort study including singleton pregnancies referred to our tertiary care center due to fetal smallness. At the time of diagnosis, fetuses were classified as SGA or FGR according to the Delphi consensus criteria, and pregnant women underwent hemodynamic assessment using a cardiac output monitor. A group of women with singleton uncomplicated pregnancies ar ≥35 weeks of gestation were recruited as controls. Cardiac output, systemic vascular resistance, stroke volume, and heart rate were measured and compared among the three groups (controls vs FGR vs SGA). The correlation between antenatal findings and neonatal outcome was also evaluated by multivariate logistic regression analysis.

RESULTS

A total of 51 women with fetal smallness were assessed at 34.8 ± 2.6 weeks. SGA and FGR were diagnosed in 22 and 29 cases, respectively. The control group included 61 women assessed at 36.5 ± 0.8 weeks of gestation. Women with FGR had a lower cardiac output Z-score (respectively, -1.3 ± 1.2 vs -0.4 ± 0.8 vs -0.2 ± 1.0; P < .001) and a higher systemic vascular resistance Z-score (respectively, 1.2 ± 1.2 vs 0.2 ± 1.1 vs -0.02 ± 1.2; P < .001) compared with both SGA and controls, whereas no difference in the hemodynamic parameters was found between women with SGA and controls. The incidence of neonatal intensive care unit admission did not differ between SGA and FGR fetuses (18.2% vs 41.4%; P = .13), but FGR fetuses had a longer hospitalization compared with SGA fetuses (14.2 ± 17.7 vs 4.5 ± 1.6 days; P = .02). Multivariate analysis showed that the cardiac output Z-score at diagnosis (P = .012) and the birthweight Z-score (P = .007) were independent predictors of the length of neonatal hospitalization.

CONCLUSIONS

Different maternal hemodynamic profiles characterize women with SGA or FGR fetuses. Furthermore, a negative correlation was found between the maternal cardiac output and the length of neonatal hospitalization.

MiRNAs Regulating Oxidative Stress: A Correlation with Doppler Sonography of Uteroplacental Complex and Clinical State Assessments of Newborns in Fetal Growth Restriction

Overproduction of reactive oxygen species (ROS) and, as a result, uncontrolled oxidative stress (OS) can play a central role in disorders of fetal hemodynamics and subsequent development of adverse perinatal outcomes in newborns with fetal growth restriction (FGR). Given the epigenetic nature of such disorders, the aim of our study was to evaluate the expression of miRNAs associated with OS and endothelial dysfunction (miR-27a-3p, miR-30b-5p, miR-125b-5p, miR-221-3p, miR-451a and miR-574-3p) in umbilical cord blood using real-time quantitative RT-PCR. ΜiRNA expression was evaluated in patients with FGR delivery before (n = 9 pregnant) and after 34 weeks of gestation (n = 13 pregnant), and the control groups corresponding to the main groups by gestational age (13 pregnant women in each group, respectively). A significant increase in miR-451a expression was detected in late-onset FGR and correlations with fetoplacental and cerebral circulation were established (increase of resistance in the umbilical artery (pulsatility index, PI UA (umbilical artery): r = −0.59, p = 0.001) and a decrease in cerebral blood flow (CPR: r = 0.48, p = 0.009)). The change in miR-125b-5p expression in the placenta is associated with reduced Doppler of cerebral hemodynamics (CPR: r = 0.73, p = 0.003; PI MCA (middle cerebral artery): r = 0.79, p = 0.0007), and newborn weight (r = 0.56, p = 0.04) in early-onset FGR. In addition, significant changes in miR-125b-5p and miR-451a expression in umbilical cord blood plasma were found in newborns with neonatal respiratory distress syndrome (NRDS) (in early-onset FGR) and very low birth weight (VLBW) (in late-onset FGR). A number of key signaling pathways have been identified in which the regulation of the studied miRNAs is involved, including angiogenesis, neurotrophin signaling pathway and oxidative stress response. In general, our study showed that changes of the redox homeostasis in the mother-placenta-fetus system in FGR and subsequent perinatal outcomes may be due to differential expression of oxidative stress-associated miRNAs.

Maternal Cardiovascular Dysfunction is Associated with Hypoxic Cerebral and Umbilical Doppler Changes

We investigate the relationship between maternal cardiovascular (CV) function and fetal Doppler changes in healthy pregnancies and those with pre-eclampsia (PE), small for gestational age (SGA) or fetal growth restriction (FGR). This was a three-centre prospective study, where CV assessment was performed using inert gas rebreathing, continuous Doppler or impedance cardiography. Maternal cardiac output (CO) and peripheral vascular resistance (PVR) were analysed in relation to the uterine artery, umbilical artery (UA) and middle cerebral artery (MCA) pulsatility indices (PI, expressed as z-scores by gestational week) using polynomial regression analyses, and in relation to the presence of absent/reversed end diastolic (ARED) flow in the UA. We included 81 healthy controls, 47 women with PE, 65 with SGA/FGR and 40 with PE + SGA/FGR. Maternal CO was inversely related to fetal UA PI and positively related to MCA PI; the opposite was observed for PVR, which was also positively associated with increased uterine artery impedance. CO was lower (z-score 97, p = 0.02) and PVR higher (z-score 2.88, p = 0.02) with UA ARED flow. We report that maternal CV dysfunction is associated with fetal vascular changes, namely raised impedance in the fetal-placental circulation and low impedance in the fetal cerebral vessels. These findings are most evident with critical UA Doppler changes and represent a potential mechanism for therapeutic intervention.

Clinical impact of Doppler reference charts on management of small-for-gestational-age fetuses: need for standardization

OBJECTIVE

To assess clinical variability in the management of small-for-gestational-age (SGA) fetuses according to different published Doppler reference charts for umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler indices and cerebroplacental ratio (CPR).

METHODS

We performed a systematic search of MEDLINE, EMBASE, CINAHL and the Web of Science databases from 1954 to 2018 for studies with the sole aim of creating fetal Doppler reference values for UA, MCA and CPR. The top cited articles for each Doppler parameter were included. Variability in Doppler values at the following clinically relevant cut-offs was assessed: UA-pulsatility index (PI) > 95^th percentile; MCA-PI < 5^th percentile; and CPR < 5^th percentile. Variability was calculated for each week of gestation and expressed as the percentage difference between the highest and lowest Doppler value at the clinically relevant cut-offs. Simulation analysis was performed in a cohort of SGA fetuses (n = 617) to evaluate the impact of this variability on clinical management.

RESULTS

From a total of 40 studies that met the inclusion criteria, 19 were analyzed (13 for UA-PI, 10 for MCA-PI and five for CPR). Wide discrepancies in reported Doppler reference values at clinically relevant cut-offs were found. MCA-PI showed the greatest variability, with differences of up to 51% in the 5^th percentile value at term. Variability in the 95^th percentile of UA-PI and the 5^th percentile of CPR at each gestational week ranged from 21% to 41% and 15% to 33%, respectively. As expected, on simulation analysis, these differences in Doppler cut-off values were associated with significant variation in the clinical management of SGA fetuses, despite using the same protocol.

CONCLUSIONS

The choice of Doppler reference chart can result in significant variation in the clinical management of SGA fetuses, which may lead to suboptimal outcomes and inaccurate research conclusions. Therefore, an attempt to standardize fetal Doppler reference ranges is needed. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

International gestational age-specific centiles for umbilical artery Doppler indices: a longitudinal prospective cohort study of the INTERGROWTH-21st Project

BACKGROUND

Reference values for umbilical artery Doppler indices are used clinically to assess fetal well-being. However, many studies that have produced reference charts have important methodologic limitations, and these result in significant heterogeneity of reported reference ranges.

OBJECTIVES

To produce international gestational age-specific centiles for umbilical artery Doppler indices based on longitudinal data and the same rigorous methodology used in the original Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project.

STUDY DESIGN

In Phase II of the INTERGROWTH-21st Project (the INTERBIO-21st Study), we prospectively continued enrolling pregnant women according to the same protocol from 3 of the original populations in Pelotas (Brazil), Nairobi (Kenya), and Oxford (United Kingdom) that had participated in the Fetal Growth Longitudinal Study. Women with a singleton pregnancy were recruited at <14 weeks' gestation, confirmed by ultrasound measurement of crown-rump length, and then underwent standardized ultrasound every 5±1 weeks until delivery. From 22 weeks of gestation umbilical artery indices (pulsatility index, resistance index, and systolic/diastolic ratio) were measured in a blinded fashion, using identical equipment and a rigorously standardized protocol. Newborn size at birth was assessed using the international INTERGROWTH-21st Standards, and infants had detailed assessment of growth, nutrition, morbidity, and motor development at 1 and 2 years of age. The appropriateness of pooling data from the 3 study sites was assessed using variance component analysis and standardized site differences. Umbilical artery indices were modeled as functions of the gestational age using an exponential, normal distribution with second-degree fractional polynomial smoothing; goodness of fit for the overall models was assessed.

RESULTS

Of the women enrolled at the 3 sites, 1629 were eligible for this study; 431 (27%) met the entry criteria for the construction of normative centiles, similar to the proportion seen in the original fetal growth longitudinal study. They contributed a total of 1243 Doppler measures to the analysis; 74% had 3 measures or more. The healthy low-risk status of the population was confirmed by the low rates of preterm birth (4.9%) and preeclampsia (0.7%). There were no neonatal deaths and satisfactory growth, health, and motor development of the infants at 1 and 2 years of age were documented. Only a very small proportion (2.8%-6.5%) of the variance of Doppler indices was due to between-site differences; in addition, standardized site difference estimates were marginally outside this threshold in only 1 of 27 comparisons, and this supported the decision to pool data from the 3 study sites. All 3 Doppler indices decreased with advancing gestational age. The 3rd, 5th 10th, 50th, 90th, 95th, and 97th centiles according to gestational age for each of the 3 indices are provided, as well as equations to allow calculation of any value as a centile and z scores. The mean pulsatility index according to gestational age = 1.02944 + 77.7456*(gestational age)-2 - 0.000004455*gestational age3.

CONCLUSION

We present here international gestational age-specific normative centiles for umbilical artery Doppler indices produced by studying healthy, low-risk pregnant women living in environments with minimal constraints on fetal growth. The centiles complement the existing INTERGROWTH-21st Standards for assessment of fetal well-being.

Perioperative fetal hemodynamic changes in twin-twin transfusion syndrome and neurodevelopmental outcome at two years of age

Objective

To investigate whether perioperative fetal hemodynamic changes in twin‐to‐twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years.

Methods

Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008‐2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley‐III cognitive/motor developmental test‐score > 2SD below the mean.

Results

Long‐term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA‐PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17‐21.05, P = .03), a change from normal umbilical artery pulsatility index (UA‐PI) presurgery to UA‐PI >p95 postsurgery (OR 4.19; 95% CI: 1.04‐16.87, P = .04), a change from normal to MCA‐PSV >1.5MoM (OR 4.75; 95% CI: 1.43‐15.77, P = .01).

Conclusion

Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome.

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.

In vivo kinetic study of materno-fetal fatty acid transfer in obese and normal weight pregnant women

KEY POINTS

Placental structure and function can be modified as a result of maternal obesity affecting materno-fetal fatty acids (FA) transport. We report for the first time, in humans and in vivo, the kinetics of placental FA transfer in normo-weight and in normolipemic obese pregnant women using stable isotopes. The administration of different tracer FA with similar behaviour to the mother at different time points allows the collection of kinetic information on materno-fetal transfer of FA despite only one sample of placenta and cord can be collected per subject. Computational modelling showed a good fit to the data when considering all maternal plasma lipid classes but not when based only on non-esterified FA. The novel approach using multiple tracer FA administration combined with computational modelling shows a consistent time course of placental tracer FA and predicted total FA accumulation.

ABSTRACT

We analyse for the first time the in vivo materno-fetal kinetic transfer of fatty acids (FA) labelled with stable isotopes in control and obese (OB) pregnant women. Labelled FA with a similar metabolism (stearic acid: ¹³ C-SA; palmitic acid: ¹³ C-PA; oleic acid: ¹³ C-OA) were orally administered at -4 h, -8 h and -12 h, respectively prior to elective caesarean section to 10 pregnant women with a body mass index >30 (OB) and 10 with a body mass index in the range 20-25 (NW). Placenta, venous and arterial cord blood were collected obtaining a wide range of FA enrichments. A combined experimental and computational modelling analysis was applied. FA fractional synthesis rate (FSR) in placenta was 11-12% h^-1 . No differences were observed between NW and normo-lipidemic OB. It was not possible to estimate FA FSR in cord blood with this oral bolus dose approach. Computational modelling demonstrated a good fit to the data when all maternal plasma lipid classes were included but not with modelling based only on the non-esterified FA fraction. The estimated materno-fetal ¹³ C-FA transfer was ∼1%. In conclusion, our approach using multiple ¹³ C-FA tracers allowed us to estimated FSR in placental/maternal plasma but not in fetal/maternal compartments. Computational modelling showed a consistent time course of placental ¹³ C-FA transfer and predicted total fetal FA accumulation during the experiment. We conclude that, in addition to non-esterified FA fraction in the maternal circulation, maternal plasma very low-density lipoprotein and other lipoproteins are important contributors to placental FA transfer to the fetus.

Short-Term Flow Changes in Monochorionic Survivor Twins after Ultrasound-Guided Umbilical Cord Occlusion

OBJECTIVE

To determine hemodynamic changes by Doppler ultrasound of the living fetus during 24 h after umbilical cord occlusion (UCO) in monochorionic diamniotic (MCDA) twin pregnancies.

METHOD

We conducted a prospective observational study on fetuses undergoing UCO from 2015 to 2017. Doppler parameters peak systolic velocity (PSV) and umbilical pulsatility index (PI) were obtained in the middle cerebral artery (MCA), umbilical artery (UA) and ductus venosus (DV) before and right after UCO, and at 1, 3, 6, 12, and 24 h after. We used multiple of the median (MoM) to adjust for gestational age. Spaghetti plots visualized flow changes over time. Mixed model adjusting for paired longitudinal data compared the values at different time points.

RESULTS

A total of 16 women were included. MCA-PSV dropped within the first hour after surgery from 0.91 to 0.82 MoM (p = 0.08). MCA-PI and UA-PI increased in the first hour from 0.75 to 0.91 MoM (p = 0.02) and 0.94 to 0.98 MoM (p = 0.22), respectively. The DV-PIV increased to 1.14 MoM 3 h after surgery (p = 0.07). The spaghetti plots illustrated the small changes within the first hours and showed a stabilization of flow measurements near initial values 24 h after UCO.

CONCLUSION

Within the first hours after UCO the circulation of the survivor twin undergoes small hemodynamic changes.

Altered materno-fetal transfer of 13C-polyunsaturated fatty acids in obese pregnant women

BACKGROUND & AIMS

Maternal obesity at conception is considered a major predictor of offspring obesity. This could by driven at least in part by an altered placental fat transfer. However, the pathophysiological mechanisms involved are not fully understood. We investigated the in vivo materno-fetal transfer of fatty acids (FAs) in obese pregnant women using stable isotopes.

METHODS

Ten obese and ten normo-weight pregnant women (control) received orally a bolus of ¹³C-labeled FAs 12 h before elective caesarean section: oleic acid (¹³C-OA), linoleic acid (¹³C-LA) and docosahexaenoic acid (¹³C-DHA). Maternal blood samples were collected at -12 (basal), -8, -4, -2, 0 h relative to the time of cesarean section. At the time of birth, arterial and venous cord bloods as well as placental tissue were collected. FAs composition was determined by gas-liquid chromatography and isotopic enrichment by gas chromatography-combustion-isotope ratio mass spectrometry.

RESULTS

Maternal plasma insulin and placental weight tended to higher values in obese pregnant women although they did not present serum hyperlipidemia. Higher concentrations of ¹³C-LA and ¹³C-DHA were found in non-esterified FAs fraction in maternal plasma of obese mothers. The ratio of placental uptake for ¹³C-LA and ¹³C-DHA was lower in obese women compared to normal weight pointing toward a limited capacity of FA placental transfer, especially of essential FAs. Maternal insulin was associated to this lower placenta/maternal plasma ratio for both ¹³C-LA (R = -0.563, P = 0.012) and ¹³C-DHA (R = -0.478, P = 0.033). In addition, the ratio cord/maternal plasma of ¹³C-LA was significantly lower in obese women compared to controls.

CONCLUSIONS

In conclusion, obese mothers without hyperlipidemia showed a reduced materno-fetal transfer of polyunsaturated FAs which could affect fetal development. This affect dietary recommendation for obese pregnant women.

TRIAL REGISTRY NUMBER

ISRCTN69794527.

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.

Cerebroplacental ratio assessment in early labor in uncomplicated term pregnancy and prediction of adverse perinatal outcome: prospective multicenter study

OBJECTIVE

It has been suggested that the use of Doppler ultrasound in term pregnancies with normal-sized fetuses is able to identify those at high risk of subclinical placental function impairment. The objective of this study was to evaluate the relationship between cerebroplacental ratio (CPR) measured in early labor and perinatal and delivery outcomes in a cohort of uncomplicated singleton term pregnancies.

METHODS

This was a prospective multicenter observational study conducted at three tertiary centers between January 2016 and July 2017. Low-risk term pregnancies, defined by the absence of maternal morbidity or pregnancy complication, accompanied by normal ultrasound and clinical screening of fetal growth in the third trimester, with spontaneous onset of labor were included. Umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler was assessed on admission for early labor. All measurements were performed in between uterine contractions and according to international standards. CPR was computed by dividing MCA pulsatility index by UA pulsatility index and converted into multiples of the median (MoM) in order to adjust for gestational age. Doctors and midwives involved in the clinical management of the women were blinded to the results of the Doppler evaluation. Mode of delivery and perinatal outcome were compared between pregnancies with reduced CPR MoM, defined as CPR MoM within the lowest decile of the study population, and those with normal CPR MoM. Receiver-operating characteristics curve analysis was used to assess the predictive performance of CPR for obstetric intervention due to fetal distress and composite adverse perinatal outcome.

RESULTS

Overall, 562 women were included. The rate of obstetric intervention for suspected fetal distress in labor was more than three times higher among cases with reduced CPR MoM compared to those with normal CPR MoM (9/54 (16.7%) vs 28/508 (5.5%); P = 0.004). Furthermore, a significantly higher rate of composite adverse perinatal outcome was found in fetuses with CPR MoM < 10^th percentile compared to those with CPR MoM ≥ 10^th percentile (6/54 (11.1%) vs 19/508 (3.7%); P = 0.012). CPR had low sensitivity and low positive predictive value for prediction of obstetric intervention due to fetal distress (24.3% and 18.0%, respectively) and composite adverse perinatal outcome (24.0% and 11.1%, respectively).

CONCLUSIONS

Data on a wide cohort of low-risk term pregnancies in early labor showed that, while reduced CPR is associated with a higher risk of obstetric intervention due to fetal distress and composite adverse perinatal outcome, it is a poor predictor of adverse perinatal outcome. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Reference ranges for Doppler indices of umbilical and fetal middle cerebral arteries and cerebroplacental ratio: systematic review

OBJECTIVE

To assess studies reporting reference ranges for umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler indices and cerebroplacental ratio (CPR), using a set of predefined methodological quality criteria for study design, statistical analysis and reporting methods.

METHODS

This was a systematic review of observational studies in which the primary aim was to create reference ranges for UA and MCA Doppler indices and CPR in fetuses of singleton gestations. A search for relevant articles was performed in MEDLINE, EMBASE, CINAHL, Web of Science (from inception to 31 December 2016) and references of the retrieved articles. Two authors independently selected studies, assessed the risk of bias and extracted the data. Studies were scored against a predefined set of independently agreed methodological criteria and an overall quality score was assigned to each study. Linear multiple regression analysis assessing the association between quality scores and study characteristics was performed.

RESULTS

Thirty-eight studies met the inclusion criteria. The highest potential for bias was noted in the following fields: 'ultrasound quality control measures', in which only two studies demonstrated a comprehensive quality-control strategy; 'number of measurements taken for each Doppler variable', which was apparent in only three studies; 'sonographer experience', in which no study on CPR reported clearly the experience or training of the sonographers, while only three studies on UA Doppler and four on MCA Doppler did; and 'blinding of measurements', in which only one study, on UA Doppler, reported that sonographers were blinded to the measurement recorded during the examination. Sample size estimations were present in only seven studies. No predictors of quality were found on multiple regression analysis. Reference ranges varied significantly with important clinical implications for what is considered normal or abnormal, even when restricting the analysis to the highest scoring studies.

CONCLUSIONS

There is considerable methodological heterogeneity in studies reporting reference ranges for UA and MCA Doppler indices and CPR, and the resulting references have important implications for clinical practice. There is a need for the standardization of methodologies for Doppler velocimetry and for the development of reference standards, which can be correctly interpreted and applied in clinical practice. We propose a set of recommendations for this purpose. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Fetal Portal System Flowmetry and Intra-Amniotic Inflammation in Preterm Prelabor Rupture of Membranes

OBJECTIVES

To determine the pulsatility index (PI) in the fetal splenic vein, the main portal vein, the left portal vein, and the ductus venosus with respect to the presence or absence of intra-amniotic inflammation (IAI) in preterm prelabor rupture of membranes (PPROM).

METHOD

Women with singleton pregnancies and PPROM, ranging in gestational age from 22+0 to 36+6 weeks, were included. Amniotic fluid samples were obtained by transabdominal amniocentesis and the amniotic fluid level of interleukin-6 (IL-6) was assessed by a point-of-care test. Doppler examination of the selected veins was performed, and the PI was assessed. IAI was defined as amniotic fluid levels of IL-6 ≥745 pg/mL.

RESULTS

In total, 42 women were included. Fetuses with IAI compared with those without IAI exhibited a higher PI in the splenic vein (p = 0.005) and the main portal vein (p = 0.05). No differences were observed in the left portal vein PI (p = 0.36) and the ductus venosus PI (p = 0.98).

CONCLUSION

IAI was associated with increased fetal splenic vein PI and main portal vein PI in PPROM. The absence of changes in the left portal vein PI and ductus venosus PI supports the local cause of the finding.

The use of actograph in the assessment of fetal well-being

Purpose: Third trimester maternal perception of fetal movements is often used to assess fetal well-being. However, its true clinical value is unknown, primarily because of the variability in subjective quantification. The actograph, a technology available on most cardiotocograph machines, quantifies movements, but has never previously been investigated in relation to fetal health and existing monitoring devices. The objective of this study was to quantify actograph output in healthy third trimester pregnancies and investigate this in relation to other methods of assessing fetal well-being.Methods: Forty-two women between 24 and 34 weeks of gestation underwent ultrasound scan followed by a computerized cardiotocograph (CTG). Post capture analysis of the actograph recording was performed and expressed as a percentage of activity over time. The actograph output results were analyzed in relation to Doppler, ultrasound and CTG findings expressed as z-score normalized for gestation.Results: There was a significant association between actograph output recording and estimated fetal weight Z-score (R = 0.546, p ≤ .005). This activity was not related to estimated fetal weight. Increased actograph activity was negatively correlated with umbilical artery pulsatility index Z-score (R = -0.306, p = .049) and middle cerebral artery pulsatility index Z-score (R = -0.390, p = .011).Conclusion: Fetal movements assessed by the actograph are associated both with fetal size in relation to gestation and fetoplacental Doppler parameters. It is not the case that larger babies move more, however, as the relationship with actograph output related only to estimated fetal weight z-score. These findings suggest a plausible link between the frequency of fetal movements and established markers of fetal health.RATIONALEThe objective of this study was to quantify actograph output in healthy third trimester pregnancies and investigate this in relation to other methods of assessing fetal well-being. This is a widely available method of assessing fetal movements objectively, which has been shown to be an important marker of fetal health. This research is novel in the fact that actograph has never been truly investigated in relation to fetal well-being, despite being available on most cardiotocograph (CTG) machines.Our results show that fetal movements assessed by the actograph are associated both with fetal size in relation to gestation and fetoplacental Doppler parameters. If this proves to be true, smaller babies that move less maybe at particular perinatal risk.

Uterine and fetal placental Doppler indices are associated with maternal cardiovascular function

BACKGROUND

The mechanism underlying fetal-placental Doppler index changes in preeclampsia and/or fetal growth restriction are unknown, although both are associated with maternal cardiovascular dysfunction.

OBJECTIVE

We sought to investigate whether there was a relationship between maternal cardiac output and vascular resistance and fetoplacental Doppler findings in healthy and complicated pregnancy.

STUDY DESIGN

Women with healthy pregnancies (n=62), preeclamptic pregnancies (n=13), preeclamptic pregnancies with fetal growth restriction (n=15), or fetal growth restricted pregnancies (n=17) from 24-40 weeks gestation were included. All of them underwent measurement of cardiac output with the use of an inert gas rebreathing technique and derivation of peripheral vascular resistance. Uterine and fetal Doppler indices were recorded; the latter were z scored to account for gestation. Associations were determined by polynomial regression analyses.

RESULTS

Mean uterine artery pulsatility index was higher in fetal growth restriction (1.37; P=.026) and preeclampsia+fetal growth restriction (1.63; P=.001) but not preeclampsia (0.92; P=1) compared with control subjects (0.8). There was a negative relationship between uterine pulsatility index and cardiac output (r²=0.101; P=.025) and umbilical pulsatility index z score and cardiac output (r²=0.078; P=.0015), and there were positive associations between uterine pulsatility index and peripheral vascular resistance (r²=0.150; P=.003) and umbilical pulsatility index z score and peripheral vascular resistance (r²= 0.145; P=.001). There was no significant relationship between cardiac output and peripheral vascular resistance with cerebral Doppler indices.

CONCLUSION

Uterine artery Doppler change is abnormally elevated in fetal growth restriction with and without preeclampsia, but not in preeclampsia, which may explain the limited sensitivity of uterine artery Doppler changes for all these complications when considered in aggregate. Furthermore, impedance within fetoplacental arterial vessels is at least, in part, associated with maternal cardiovascular function. This relationship may have important implications for fetal surveillance and would inform therapeutic options in those pathologic pregnancy conditions currently, and perhaps erroneously, attributed purely to placental maldevelopment. Uterine and fetal placental Doppler indices are associated significantly with maternal cardiovascular function. The classic description of uterine and fetal Doppler changes being initiated by placental maldevelopment is a less plausible explanation for the pathogenesis of the conditions than that relating to maternal cardiovascular changes.

Doppler measurements of both umbilical arteries do not improve predictive value for adverse perinatal outcomes in small-for-gestational age fetuses

OBJECTIVE

To assess agreement of Doppler ultrasound measurements of the two umbilical arteries in small-for gestational age (SGA) fetuses, and to compare discriminative ability between the two arteries for adverse perinatal outcome.

STUDY DESIGN

We analysed a prospective cohort of singleton SGA pregnancies, in which the pulsatility index (PI) of both umbilical arteries was standardly measured by Doppler ultrasound in the free-floating umbilical cord. The outcome of interest was a composite adverse outcome, defined as perinatal death, Apgar score <7 at 5 min, cesarean section for fetal distress, and neonatal intensive care unit admission.

RESULTS

A total of 531 measurements were performed in 124 patients. Mean absolute difference between PI measured in the two umbilical arteries was 0.14 (95% CI: 0.12 to 0.15), showing good agreement with an ICC of 0.830 (95% CI: 0.801 to 0.854). Perinatal outcomes were available for 101 patients, of which 48 patients (48%) had a composite adverse perinatal outcome. We found no significant differences between AUCs for prediction of an adverse outcome based on lowest, highest and mean PI values in the two umbilical arteries (AUCs = 0.75, 0.74, 0.75 with p = 0.91). As a comparison, the AUC of a PI value obtained in a single, randomly selected umbilical artery was 0.74.

CONCLUSION

The two umbilical arteries show good agreement in terms of their PI values in the free-floating umbilical cord, and do not differ in terms of their discriminative ability for adverse perinatal outcome in SGA fetuses. We found no evidence of an added value of standard Doppler measurement of both umbilical arteries.

Fetal growth standards in gastroschisis: Reference values for ultrasound measurements

OBJECTIVES

The objectives of this study were to create growth curves based on ultrasonography biometric parameters of fetuses with gastroschisis, comparing them with normal growth standards, and to analyze umbilical artery (UA) Doppler velocimetry patterns.

METHODS

A cohort study of 72 fetuses with gastroschisis, at gestational ages between 14 and 39 weeks was designed. Mean and standard deviation were calculated, with the 5th, 10th, 50th, 90th, and 95th centiles being established for biometric parameters according to gestational age. Curves were obtained, comparing with normal reference via the Mann-Whitney test. UA Doppler velocimetry patterns were obtained.

RESULTS

A total of 434 examinations were performed, and centiles were established for biparietal diameter, head circumference, abdominal circumference, femur length, and estimated fetal weight. A significant difference was observed between the gastroschisis measurements when compared to control, with all curves shifted downwards. Abdominal circumference was the parameter presenting the largest difference. Estimated fetal weight was also lower, with mean difference of 256.3 ± 166.8 g for the 50th centile (P < .0001). UA Doppler velocimetry was normal in 97.5%.

CONCLUSIONS

Fetuses with gastroschisis show symmetrical growth deficits in the second and third trimesters, with normal UA Doppler velocimetry. These results reinforce the hypothesis that they are constitutionally smaller, yet not restricted because of placental insufficiency.

Tinzaparin for the treatment of foetal growth retardation: An open-labelled randomized clinical trial

OBJECTIVE

Foetal growth retardation (FGR) is a leading cause of perinatal death and long-term harms at survivors. Placental infarction plays a role in FGR, yet, no trials have evaluated whether low molecular weight heparins increase birth weight in ongoing FGR pregnancies.

METHODS

An open-labelled randomized trial in Denmark during 2011-2016, including singleton pregnant women with FGR (estimated foetal weight < 2.3 percentile) diagnosed before gestational weeks 32. Participants were randomly assigned using sealed, blinded envelopes 1:1 to tinzaparin (4500 IU daily until 37 gestational weeks) or no tinzaparin. The primary outcomes were the observed birthweight relative to the expected for gestational age and gender, and foetal growth rates in the two trial groups evaluated by an intention to treat analysis.

RESULTS

We enrolled 53 women. The mean gestational age was 261 days in the tinzaparin group and 246 days in the no treatment group. The mean birth weight was 2229 g in the tinzaparin group compared to 1968 g in the no treatment group. However, the birth weight relative to the expected from gestational age and gender was only 2.5 percentage points higher in the tinzaparin group [-5.1 to 10.0] (p = 0.51). The foetal growth rate during follow-up was 124 g/week in the tinzaparin group and 119 g/week in the no treatment group, a difference of 5 g/week [-19 to 29] (p = 0.67). Two perinatal deaths both occurred in the no treatment group.

CONCLUSION

We found no evidence of a tinzaparin effect on the foetal growth rate or the birth weight after adjustment for gestational age.

Postpartum placental CT angiography in normal pregnancies and in those complicated by diabetes mellitus

INTRODUCTION

Pregnancy complicated by diabetes mellitus (DM) is a central obstetric problem often complicated by fetal macrosomia and increased risk of intrapartum asphyxia. This risk might be explained by fetoplacental vascular abnormalities. This study aimed to investigate the fetoplacental vascular volume by placental CT angiography in normal pregnancies and in pregnancies complicated by type 1 DM (T1DM), diet controlled gestational DM (GDMd), and insulin treated gestational DM (GDMi).

METHODS

Postpartum, barium contrast enhanced placental CT angiography was performed in 27 normal pregnancies and 25 DM pregnancies (8 T1DM, 8 GDMd, and 9 GDMi). The fetoplacental vascular volume/placenta weight (FVV/PW)-ratio and fetoplacental vascular volume/birth weight (FVV/BW)-ratio of each diabetic group were compared to the normal group with multiple regression analysis adjusted for GA. In all pregnancies a standardized histopathological placental examination was performed postpartum.

RESULTS

In normal pregnancies, the fetoplacental vascular volume increased with GA (p < 0.001), placental weight (p < 0.001), and birth weight (p < 0.001). In T1DM and GDMi pregnancies, the gestational age adjusted placental weight and the birth weight were increased when compared to normal pregnancies (p < 0.05). The FVV/BW-ratio was significantly reduced in both T1DM and GDMi pregnancies when compared to normal pregnancies (p = 0.003 and p = 0.009, respectively).

DISCUSSION

This study demonstrates, that in insulin treated DM pregnancies the fetus as well as the placenta is larger than normal. However, despite a large placenta, a relatively smaller fetoplacental vascular volume supplies the macrosomic fetus. This finding might explain why fetuses from insulin treated DM pregnancies have high vulnerability to intrauterine and intrapartum asphyxia.

Perinatal outcome and placental apoptosis in patients with late-onset pre-eclampsia and abnormal uterine artery Doppler at diagnosis

OBJECTIVE

To determine the rate of placental apoptosis and adverse perinatal outcome in patients with late-onset pre-eclampsia (PE) and abnormal uterine artery (UtA) Doppler at diagnosis.

METHODS

This was a prospective cohort study of women with singleton pregnancy diagnosed with late PE, performed between August 2011 and January 2014 at the Maternal-Fetal Medicine Unit of Hospital Carlos Van Buren. Patients were stratified according to UtA Doppler status at diagnosis (pulsatility index (PI) ≤ or > 95^th percentile). Logistic regression analysis was performed to identify associations between abnormal UtA Doppler and adverse maternal and perinatal outcomes. In a subset of this cohort for whom placental samples were available, immunohistochemical analysis of the placenta was performed to identify the rate of apoptosis and its association with UtA Doppler by comparing samples from those with normal and those with abnormal UtA Doppler and normotensive controls. Non-parametric linear trend analysis was performed for assessment of the apoptotic index.

RESULTS

Eighty-six patients were included in the final analysis. Of these, UtA-PI was above the 95^th percentile in 33 (38.4%) patients. Gestational age at diagnosis and delivery were significantly lower in this group compared with patients with normal UtA Doppler. Abnormal UtA Doppler was associated with increased risk of severe PE (odds ratio (OR) = 7.5; 95% CI, 2.76-20.46; P < 0.001), late preterm delivery (OR = 13.7; 95% CI, 4.53-41.46; P < 0.001), small-for-gestational age at birth (OR = 12.3; 95% CI, 3.17-47.57; P < 0.001) and admission to the neonatal intensive care unit (OR = 12.8; 95% CI, 2.61-62.36; P = 0.002). Moreover, UtA Z-score demonstrated a significant inverse correlation with birth-weight Z-score (r = -0.34; P = 0.0013). Mean placental apoptotic index demonstrated an ascending linear trend according to UtA Doppler status (P = 0.04).

CONCLUSIONS

In patients with late PE, UtA Doppler was useful for clinical classification and as an indicator of placental histological findings. Correlation between UtA Doppler and the apoptotic index provides new evidence of a subgroup of late PE with a placental origin. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Maternal Serum B Cell activating factor in hypertensive and normotensive pregnancies

OBJECTIVES

The objective of this study was the analysis of B-Cell Activating Factor (BAFF) levels in pregnancies affected by PE, and in pregnancies affected by fetal growth restriction without Hypertensive disorders and its possible correlation with pulse wave velocity and cardiac output.

STUDY DESIGN

Prospective study of 69 women at 24-40 weeks gestation. Haemodynamic function was assessed in those with Pre-eclampsia (PE, n = 19), fetal growth restriction (FGR, n = 10) and healthy pregnancies (n = 40). Maternal venous BAFF levels at recruitment were measured using ELISA. We analysed the relationship between BAFF and cardiac output (CO), and BAFF and PWV (pulse wave velocity); the gold standard for assessing arterial stiffness. PWV was measured with an oscillometric device and CO using inert gas rebreathing technique. PWV and CO were converted to gestation adjusted indices (z scores).

MAIN OUTCOME MEASURES

The association between BAFF levels in PE and FGR, and the relationship of BAFF with PWV and CO.

RESULTS

BAFF was higher in PE (p = 0.03) but not in FGR (p = 0.83) when compared to healthy pregnancies. There was a positive correlation between BAFF levels and z score PWV (r = 0.25, p = 0.04), but not CO (r = -0.01, p = 0.91). BAFF levels did not change with gestational age. (r = 0.012, p = 0.925).

CONCLUSIONS

These findings provide evidence of a possible contribution of BAFF to both maternal inflammation and arterial dysfunction associated with PE. Though no relationship was found with another disorder of placentation: normotensive FGR, this condition is not thought to be associated with maternal inflammation.

Early and late preeclampsia are characterized by high cardiac output, but in the presence of fetal growth restriction, cardiac output is low: insights from a prospective study

BACKGROUND

Preeclampsia and fetal growth restriction are considered to be placentally mediated disorders. The clinical manifestations are widely held to relate to gestation age at onset with early- and late-onset preeclampsia considered to be phenotypically distinct. Recent studies have reported conflicting findings in relation to cardiovascular function, and in particular cardiac output, in preeclampsia and fetal growth restriction.

OBJECTIVE

We conducted this study to examine the possible relation between cardiac output and peripheral vascular resistance in preeclampsia and fetal growth restriction.

STUDY DESIGN

We investigated maternal cardiovascular function in relation to clinical subtype in 45 pathological pregnancies (14 preeclampsia only, 16 fetal growth restriction only, 15 preeclampsia and fetal growth restriction) and compared these with 107 healthy person observations. Cardiac output was the primary outcome measure and was assessed using an inert gas-rebreathing method (Innocor), from which peripheral vascular resistance was derived; arterial function was assessed by Vicorder, a cuff-based oscillometric device. Cardiovascular parameters were normalized for gestational age in relation to healthy pregnancies using Z scores, thus allowing for comparison across the gestational range of 24-40 weeks.

RESULTS

Compared with healthy control pregnancies, women with preeclampsia had higher cardiac output Z scores (1.87 ± 1.35; P = .0001) and lower peripheral vascular resistance Z scores (-0.76 ± 0.89; P = .025); those with fetal growth restriction had higher peripheral vascular resistance Z scores (0.57 ± 1.18; P = .04) and those with both preeclampsia and fetal growth restriction had lower cardiac output Z scores (-0.80 ± 1.3 P = .007) and higher peripheral vascular resistance Z scores (2.16 ± 1.96; P = .0001). These changes were not related to gestational age of onset. All those affected by preeclampsia and/or fetal growth restriction had abnormally raised augmentation index and pulse wave velocity. Furthermore, in preeclampsia, low cardiac output was associated with low birthweight and high cardiac output with high birthweight (r = 0.42, P = .03).

CONCLUSION

Preeclampsia is associated with high cardiac output, but if preeclampsia presents with fetal growth restriction, the opposite is true; both conditions are nevertheless defined by hypertension. Fetal growth restriction without preeclampsia is associated with high peripheral vascular resistance. Although early and late gestation preeclampsias are considered to be different diseases, we show that the hemodynamic characteristics of preeclampsia were unrelated to gestational age at onset but were strongly associated with the presence or absence of fetal growth restriction. Fetal growth restriction more commonly coexists with preeclampsia at early gestation, thus explaining the conflicting results of previous studies. Furthermore, antihypertensive agents act by reducing cardiac output or peripheral vascular resistance and are administered without reference to cardiovascular function in preeclampsia. The underlying pathology (preeclampsia, fetal growth restriction, preeclampsia and fetal growth restriction) defines cardiovascular phenotype, providing a rational basis for choice of therapy in which high or low cardiac output or peripheral vascular resistance is the predominant feature.