Abnormal Uterine Artery Doppler Research Articles

OP22.06: Systolic dysfunction in intrauterine growth restriction fetuses with abnormal uterine artery Doppler evaluated by TAPSE and MAPSE

Gestational age at scan (weeks) 35.4 ± 2.9 36.7 ± 3.0 36.2 ± 3.2 0.094 Feto-placental Doppler (z-scores) Umbilical artery pulsatility index −0.02 ± 0.54 −0.02 ± 0.60 0.16 ± 0.53 0.166 Middle cerebral artery pulsatility index 0.54 ± 0.97 0.18 ± 0.71 0.44 ± 0.94 0.146 Cerebroplacental ratio 0.21 ± 1.21 −0.06 ± 1.13 −0.06 ± 1.23 0.362 Fetal cardiac morphometry Cardiothoracic Ratio 0.28 ± 0.05 0.32 ± 0.06* 0.34 ± 0.06* <0.001 Left Sphericity Index 1.83 ± 0.32 1.67 ± 0.25* 1.59 ± 0.33* <0.001 Fetal cardiac function (z-scores) Left myocardial performance Index 0.04 ± 0.59 0.99 ± 1.09* 1.25 ± 1.09* <0.001 Tricuspid annular plane systolic excursion −0.74 ± 0.79 −1.53 ± 0.94* −1.59 ± 0.85* <0.001 Septal annular early diastolic peak velocity (E’) 0.79 ± 1.07 −0.49 ± 1.18* −0.51 ± 1.23* <0.001 Septal annular systolic peak velocity (S’) 0.88 ± 1.11 −0.33 ± 0.98* −0.39 ± 1.06* <0.001

Prediction of Preeclampsia by Midtrimester Uterine Artery Doppler Velocimetry in High-Risk and Low-Risk Women

To observe the role of uterine artery Doppler flow velocimetry at midtrimester in prediction of preeclampsia. 179 women carrying <16weeks of pregnancy, with singleton fetus and without any fetal anomaly were recruited and were divided in high-risk and low-risk group. Doppler velocimetry of uterine artery was done at 24-26weeks. Any notch in uterine artery, unilateral or bilateral, or RI>0.6, was considered abnormal. Women were followed up and development of preeclampsia noted. Sensitivity and specificity of abnormal uterine artery Doppler study for prediction of preeclampsia were 73.33 and 86.48% in high-risk and 57.14 and 95.83% in low-risk group, respectively. Relative risk with 95% confidence interval was 5.427 (2.272-12.958) in high-risk and 13.65 (5.669-32.865) in low-risk women. Doppler velocimetry of uterine artery at 24weeks can be used as a reliable screening test for prediction of preeclampsia in both high-risk and low-risk women.

Perinatal outcomes of fetal echogenic bowel

To investigate perinatal outcomes of fetal echogenic bowel (FEB). This is a retrospective observational study of FEB cases from Jan 2005-Dec 2010. Data from ultrasound and fetal medicine investigations, uterine artery Doppler (UAD), intra-partum care and neonatal outcome were obtained from Fetal Medicine, Obstetric and Neonatal Databases. There were 139 cases presenting at 21(+5) (15(+1) -35(+5) ) weeks gestation. Overall, 106/139 (76.2%) were live born (LB), 8/139 (5.8%) were complicated by intra-uterine deaths (IUD), 11/139 (7.9%) had termination of pregnancy (TOP) and 14/139 (10.1%) were lost to follow-up after 28 weeks gestation. Six had chromosomal/genetic abnormalities, two had congenital cytomegalovirus, none had cystic fibrosis.Uterine artery Doppler was normal in 106/130 (81.5%) cases. In this group, there were no cases of fetal growth restriction (FGR), 95/106 (89.6%) were LB, 1/106 (0.94%) had an IUD. In the abnormal UAD group, 17/24 (70.1%) developed FGR, 11/24 (45.8%) were LB, 4/24 (16.7%) had TOP, 7/24 (29.2%) had IUD.In total, 20/106 (18.9%) live births were admitted for specialist neonatal care, 12/20 (60%) for prematurity. Only one had primary bowel pathology. Pregnancies with FEB and screen positive UAD are at risk of adverse perinatal outcome. Primary bowel pathology is rare following the finding of FEB.

Ultrasound assessment of placental function: the effectiveness of placental biometry in a low‐risk population as a predictor of a small for gestational age neonate

The aims of the study were to establish reference ranges for placental length and thickness in a low-risk obstetric population and to assess the likelihood of a small for gestational age (SGA) neonate on the basis of placental length at 18-24 weeks' gestation. Placental length and thickness were measured by two sonographers in 520 singleton pregnancies. Uterine artery Doppler studies and a placental morphological assessment were also performed. Placental size was correlated with the birthweight centiles at delivery. A placental length <10th centile between the gestational age of 18 and 24 weeks is a significant factor associated with SGA neonate [odds ratio (OR) = 2.8, 95% CL, 1.1-6.9]. An abnormal uterine artery Doppler is a significant factor for SGA neonate (OR = 3.4, 95% CL, 1.6-7.4). There was a weak relationship between cord insertion <2 cm from the placental margin and an SGA neonate (OR = 1.8, 95% CL, 0.4-8.2). We have provided reference ranges for placental length and thickness from 18 to 24 weeks' gestation. A single measurement of placental length incorporated into the anatomy scan may assist in the early detection of a group at risk of delivering an SGA neonate.

Gebelik Komplikasyonlarının Öngörüsünde Maternal İkinci Trimester AFP, HCG, ESTRİOL Değerleri ve Uterin Arter Doppler Bulguları Arasındaki İlişkinin Değerlendirilmesi

Gebelik Komplikasyonlarının Öngörüsünde Maternal İkinci Trimester AFP, HCG, ESTRİOL Değerleri ve Uterin Arter Doppler Bulguları Arasındaki İlişkinin Değerlendirilmesi

The outcome of isolated short femur length at mid T scan

ObjectivesTo examine the outcome of fetuses diagnosed with short femur length at the time of the routine anomaly scan.MethodsThis was a retrospective review of 58 pregnancies referred to fetal medicine...

Sildenafil Citrate Rescues Fetal Growth in the Catechol- O -Methyl Transferase Knockout Mouse Model

Preeclampsia and fetal growth restriction are responsible for the majority of maternal and perinatal morbidity and mortality associated with complicated pregnancies. Although their etiologies are complex and multifactorial, both are associated with increased uterine artery resistance. Sildenafil citrate is able to rescue the dysfunction observed ex vivo in uterine arteries of women with preeclampsia. The ability of sildenafil citrate to increase uterine artery vasodilation, thereby decreasing uterine artery resistance and, hence, ameliorated preeclampsia and fetal growth restriction, was tested in a mouse model of preeclampsia, the catechol-O-methyl transferase knockout mouse (COMT(-/-)). COMT(-/-) and C57BL/6J mice were treated (0.2 mg/mL in drinking water, n=6-12) from gestational day 12.5 to 18.5. Measures of pup growth, including body weight, crown/rump length, and abdominal circumference, were reduced in COMT(-/-) mice; this was normalized after treatment with Sildenafil. COMT(-/-) mice also demonstrated abnormal umbilical Doppler waveforms, including reverse arterial blood flow velocity. This was normalized after treatment with Sildenafil. Abnormal uterine artery Doppler waveforms were not demonstrated in COMT(-/-) mice, although ex vivo responses of uterine arteries to phenylephrine were increased; moreover, treatment with Sildenafil did improve ex vivo sensitivity to an endothelium-dependent vasodilator. The data presented here demonstrate that Sildenafil can rescue pup growth and improve abnormal umbilical Doppler waveforms, providing support for a potential new therapeutic strategy targeting fetal growth restriction.

The impact of maternal body mass index on the phenotype of pre‐eclampsia: a prospective cohort study

We hypothesised that among nulliparous women with pre-eclampsia, overweight or obese women would have a different phenotype of pre-eclampsia compared with normal weight women with pre-eclampsia. Specifically, they are more likely to develop term pre-eclampsia and less likely to have indicators of impaired placental perfusion, e.g. abnormal uterine artery Doppler or a small-for-gestational-age (SGA) infant. Prospective, multicentre, cohort SCOPE study (n = 3170). New Zealand and Australia. Nulliparous women who developed pre-eclampsia. Participants were interviewed at 14-16 weeks of gestation, uterine artery Doppler studies were performed at 19-21 weeks and pregnancy outcome was tracked prospectively. Rates of abnormal uterine artery Doppler indices, term/preterm birth and SGA infants were compared between normal, overweight and obese women with pre-eclampsia. Multivariable analysis was performed to examine the association between body mass index (BMI) and term pre-eclampsia. Of 178 women with pre-eclampsia, one underweight woman was excluded and 66 (37%) were normal weight, 52 (29%) were overweight and 59 (34%) were obese. Pre-eclampsia developed preterm in 26% of women and at term in 74% of women. There were no differences in the rates of term/preterm pre-eclampsia, abnormal uterine artery Doppler indices or SGA infants between BMI groups (P > 0.10). No independent association between BMI and term pre-eclampsia was found (P = 0.56). Among women with pre-eclampsia, those who are overweight or obese in early pregnancy are not more likely to have term pre-eclampsia compared with women with a normal BMI. Overweight and obese women require vigilant surveillance for the development of preterm as well as term pre-eclampsia.

A functional variant in ANGPT1 and the risk of pregnancies with hypertensive disorders and small-for-gestational-age infants

Pregnancies complicated by pre-eclampsia and small-for-gestational-age (SGA) infants demonstrate impaired placental vascular remodelling. Angiopoietin-1 (ANG-1) is an angiogenic growth factor which regulates vascular integrity and remodelling. The TT genotype of angiopoietin 1 (ANGPT1) rs2507800 polymorphism has been associated with increased plasma ANG-1 levels compared with the AA genotype. We aimed to investigate the association between ANGPT1 rs2507800 polymorphism and pregnancies complicated by gestational hypertensive disorders and SGA infants. We also aimed to investigate whether the polymorphism was associated with abnormal uterine artery Doppler as a surrogate marker of impaired placental vascular remodelling. Genotyping data of 1361 nulliparous pregnant women, 1226 partners and 1190 infants were analysed. The prevalence of ANGPT1 rs2507800 TT genotype was reduced in women with pre-eclampsia [P = 0.01, adjusted odds ratio (aOR), 0.5; 95% confidence interval (CI), 0.3-0.9], hypertensive SGA (P = 0.04, aOR, 0.5; 95% CI, 0.2-0.9) and SGA with abnormal uterine artery Doppler (P = 0.009, aOR, 0.4. 95% CI, 0.2-0.8) compared with women with uncomplicated pregnancy. The prevalence of maternal ANGPT1 rs2507800 TT genotype was reduced in women with increased uterine artery resistance index (P = 0.03, aOR, 0.7; 95% CI, 0.5-0.9) and bilateral notching of the uterine arteries (P = 0.004, aOR, 0.6; 95% CI, 0.4-0.9). These results remained significant after correcting for multiple testing. Maternal ANGPT1 rs2507800 TT genotype is associated with a reduced risk for pre-eclampsia, hypertensive SGA and abnormal uterine artery Doppler. These findings suggest that the TT genotype may protect against these pregnancy disorders by increasing ANG-1 production at the maternal-fetal interface. The ANGPT1 rs2507800 polymorphism may have a potential role in screening women to predict the risk of these pregnancy complications. TRIAL REGISTRY NAME: Screening nulliparous women to identify the combinations of clinical risk factors and/or biomarkers required to predict pre-eclampsia, SGA babies and spontaneous preterm birth.

391: Maternal and fetal Doppler pulsatility indices predict adverse pregnancy outcome in uncomplicated pregnancies with borderline-low amniotic fluid index in the early third trimester

indices predict adverse pregnancy outcome in uncomplicated pregnancies with borderline-low amniotic fluid index in the early third trimester Kazumasa Hashimoto, Tania Kasdaglis, Sheveta Jain, Ozhan Turan, Kristin Atkins, Jerome Kopelman, Chris Harman, Ahmet Baschat University of Maryland School of Medicine, Obstetrics, Gynecology and Reproductive Sciences, Baltimore, MD, University of Maryland School of Medicine, Obstetrics & Gynecology and Reproductive Sciences, Baltimore, MD OBJECTIVE: We have reported borderline-low (BL) amniotic fluid index (AFI) in the early third trimester in uncomplicated pregnancy associated with adverse outcome. The aim of this study is to test if maternal and/or fetal Doppler indices can stratify risks of adverse perinatal outcome. STUDY DESIGN: Nested case-control study in cohort of uncomplicated pregnancy with BL-AFI (8.0-11.9) at 28.0-31.9 weeks gestation (20062010, N 173). Frequency of abnormal uterine artery Doppler pulsatility index (UtA PI), umbilical artery (UA PI) and middle cerebral artery (MCA PI) were compared between controls and those with adverse outcome, defined in categories: Antepartum (abnormal antepartum testing, stillbirth, placental abruption, preeclampsia, N 9), Delivery (emergency and/or fetal-indicated Cesarean delivery, preterm birth, N 52), Neonatal (birth weight 1.645 (90th centile) for UA PI and UtA PI, and Z-score 1.645 (10th centile) for MCA PI, defined abnormal values. RESULTS: Abnormal UtA, UA, and MCA-PI were significantly more common in all categories of adverse outcome, compared to controls. When any Doppler index is abnormal, prediction of adverse outcome had the following characteristics: Antepartum sensitivity (SN 0.88), specificity (SP 0.80), positive predictive value (PPV 0.26) and negative predictive value (NPV 0.99); Delivery (SN 0.43, SP 0.84, PPV 0.56, NPV 0.76); Neonatal (SN 0.43, SP 0.84, PPV 0.56, NPV 0.76); Composite (SN 0.39, SP 0.85, PPV 0.63, NPV 0.67). While individual Doppler indices had clinically-low predictive ability, combining UtA, UA, and MCA PI increases SN and NPV. CONCLUSION: Using these parameters, maternal and fetal Dopplers can identify cases at high-risk for adverse outcome in uncomplicated patients with borderline AFI. Measurement of all three Doppler indices helps triage such pregnancies.

Ultrasound markers for the detection of women at risk of developing pre-eclampsia

Pre-eclampsia (PE) is a consequence of an abnormal placental invasion. Uterine artery Doppler (Ut-AD) is directly related to trophoblastic invasion of the spiral arteries, which occurs before 18 weeks’ gestation. A correct interpretation of Ut-AD indices and waveform patterns requires a rigorous and standardized methodology, in particular for the definition of notches. To date, aspirin is the only treatment associated with a decreased incidence of PE, and early identification of women at risk is crucial to optimize its use. The diagnostic performance of Ut-AD as a screening test should take into account the characteristics of the population studied. In women at high-risk of PE (i.e., women with a previous history of PE), results vary from a detection rate of 63%, with 25% false-positive results for all forms of PE, to 91% detection with 5% false-positive for early PE if repeated measurements, combined with maternal characteristics, are performed. Multicenter randomized clinical trials failed to demonstrate a benefit from administering aspirin in low-risk women with abnormal Ut-AD. In unselected populations, the use of Ut-AD, alone or integrated into algorithms including maternal characteristics, cannot be recommended for clinical practice at any gestational age. Combination with biological markers is a new field of research that could improve the performance of Ut-AD.

Association of Vascular Endothelial Growth Factor &lt;emph type="ital"&gt;+936 C/T&lt;/emph&gt; Single-Nucleotide Polymorphism With Pregnancies Complicated by Small-for-Gestational-Age Babies

To examine whether single-nucleotide polymorphisms (SNPs) in VEGFA (-2578 C/A and +936 C/T) associate with small-for-gestational-age (SGA) pregnancies and to identify their effects on first-trimester placental VEGFA expression. Multicenter prospective cohort study. Adelaide, Australia, and Auckland, New Zealand. A total of 3234 nulliparous pregnant women, their partners, and their infants. The SNPs in the parent-infant trios and first-trimester placentae (n = 74) were genotyped. Placental VEGFA messenger RNA expression was determined by quantitative reverse transcription-polymerase chain reaction. Small for gestational age was defined as a birth weight less than the 10th customized birth weight percentile adjusted for maternal height, weight, parity, and ethnicity and for gestational age at delivery and infant sex. Uterine and umbilical artery Doppler was performed at 20 weeks' gestation, and resistance indices greater than the 90th percentile were considered abnormal. Of 2123 pregnancies, 1176 (55.4%) were uncomplicated and 216 (10.2%) had SGA infants. Neonatal VEGFA +936 C/T SNP associates with SGA (adjusted odds ratio [aOR], 1.6; 95% CI, 1.0-2.3), SGA with abnormal Doppler findings (aOR, 3.5; 95% CI, 1.8-7.1), lower birth weight (P = .006), customized birth weight percentile (P = .049), and abnormal uterine artery Doppler findings (OR, 2.5; 95% CI, 1.2-5.4). Maternal VEGFA +936 C/T associates with abnormal umbilical artery Doppler findings (OR, 1.5; 95% CI, 1.1-2.2). VEGFA +936 CT+TT first-trimester placentae have 36% lower VEGFA messenger RNA expression compared with CC (P = .045). Neonatal VEGFA +936 C/T associates with SGA, and the association is stronger for SGA with abnormal uterine or umbilical artery Doppler findings. The SNP also associates with reduced first-trimester placental VEGFA expression, suggesting that it may have a role in the pathogenesis of SGA. Trial Registration clinicaltrials.gov Identifier: ACTRN12607000551493.

Transdermal nitroglycerin in patients with severe pre‐eclampsia with placental insufficiency: effect on uterine, umbilical and fetal middle cerebral artery resistance indices

To evaluate the effect of transdermal nitroglycerin on Doppler velocity waveforms of the uterine, umbilical and fetal middle cerebral arteries in patients with severe pre-eclampsia. This was a prospective study of 30 singleton pregnancies (gestational age range: 24-31 weeks) with severe pre-eclampsia and abnormal uterine and umbilical artery Doppler waveforms. We compared maternal blood pressure as well as the resistance index (RI) and the pulsatility index (PI) of the uterine, umbilical and fetal middle cerebral arteries before and after application of a transdermal nitroglycerin patch (average dose 0.4 mg/h) for a period of 3 days. Intra-day comparisons before and after administration of nitroglycerin and a comparison between days 0 (no patch) and 3 after administration of the first dose of nitroglycerin were performed using ANOVA for paired samples. A significant decrease in the PI and RI of the uterine (25.3 ± 4.9% and 21.2 ± 6.2%, respectively, P < 0.001) and umbilical (23.1 ± 6.9% and 19.7 ± 6.1%, respectively, P < 0.001) arteries was noted when comparing the first day without medication against the third day with the patch. No significant change in the PI and RI of the middle cerebral artery was observed. The mean arterial blood pressure decreased from 119.5 ± 4.5 mmHg to 114.8 ± 4.4 mmHg (P < 0.05). The use of transdermal nitroglycerin in patients with severe pre-eclampsia is associated with a significant reduction in the RI and PI of the uterine and umbilical arteries, as well as of maternal blood pressure. Transdermal nitroglycerin does not affect the RI and PI of the fetal middle cerebral artery.

OP09.09: Risk of placental abruption in patients with abnormal uterine artery Doppler in the second trimester of pregnancy

OP09.09: Risk of placental abruption in patients with abnormal uterine artery Doppler in the second trimester of pregnancy

OP09.11: Third trimester abnormal uterine artery Doppler is associated with adverse pregnancy outcome

OP09.11: Third trimester abnormal uterine artery Doppler is associated with adverse pregnancy outcome

O6. Uterine artery Doppler in a risk population: What’s its role in the prediction of small for gestational age fetuses?

Objective: The aim of this retrospective study was to assess the role of uterine artery (UtA) Doppler velocimetry in the prediction of small for gestational age (SGA) fetuses in a high risk population. Methods: A population of 145 singleton high risk pregnancies was evaluated with serial UtA Doppler performed within 23 weeks (I UtADoppler) and between 23 and 30 weeks’ gestation (II UtA Doppler). Risk population was composed by women with chronic hypertension or with a previous pregnancy complicated by one of the following: preeclampsia, stillbirth, abruptio placentae, small for gestational age newborns. The association between an abnormal UtA velocimetry (Resistance Index > 0.58 and/or bilateral notch) and the probability to develop SGA fetuses was analysed. SGA fetuses were diagnosed on the base of ultrasonographic measurement of abdominal circumference below the 10 centile. Therapy with low-dose aspirin and/or Low Weight Molecular Heparin was prescribed according with a clinical protocol. Results: Gestational age at delivery, mean birth weight, abnormal UtA Doppler and Umbilical artery Doppler were significantly different between SGA fetuses and not SGA fetuses (Table 1). Particularly 30% of SGA fetuses with an abnormal UtA Doppler had also an abnormal Umbilical artery Doppler (defined as a Pulsatility Index >95 centile). Logistic regression analysis showed that only the abnormal UtA Doppler test performed between 23 and 30 weeks’ gestation independently correlated with SGA fetuses, otherwise ASA was a significant protective factor for SGA fetuses (Table 2). Persistence of abnormal UtA Doppler was associated with a statistically higher rate of SGA. Conclusion: An abnormal UtA Doppler in the late second or early third trimester remained the variable significantly related with SGA fetuses; therefore UtA Doppler evaluation between 23 and 30 weeks could be useful for the management of high risk population. ASA was a significant protective factor for intrauterine growth.

Utility of Head/Abdomen Circumference Ratio in the Evaluation of Severe Early-Onset Intrauterine Growth Restriction

ObjectiveTo determine whether the predominant phenotype of intrauterine growth restriction (IUGR) is symmetric or asymmetric in severe, early-onset disease due to placental insufficiency. MethodsWe conducted a retrospective chart review of high-risk pregnant women with severe, early-onset IUGR who were delivering at < 33+0 weeks’ gestation at Mount Sinai Hospital from 2001 to 2010. Ultrasound images were reviewed for fetal biometry, amniotic fluid volume, and uterine and umbilical Doppler flow studies within seven days of delivery, and the frequency of head circumference/abdominal circumference ratio ≥ 95th percentile for gestation was determined. ResultsSixty-two of 107 pregnancies (58%) with early-onset IUGR had an elevated HC/AC ratio (≥95th percentile), which was more than 10-fold greater than the expected proportion (P < 0.001). High rates of severe preeclampsia (53%), abnormal amniotic fluid (70%), and abnormal uterine artery Doppler studies (78%) indicated placental insufficiency. ConclusionFetuses with severe placental IUGR in the second trimester are more likely to have an asymmetric phenotype. This is in contrast to the current belief that asymmetric IUGR is confined to third trimester IUGR.

Preeclampsia, a disease of the maternal endothelium: the role of antiangiogenic factors and implications for later cardiovascular disease.

Preeclampsia is a clinical syndrome defined as the new onset of hypertension and proteinuria during the second half of pregnancy.1 It afflicts 3% to 5% of pregnancies and is a leading cause of maternal mortality, especially in developing countries.2,3 Because the only known remedy is delivery of the placenta, in developed countries preeclampsia is an important cause of premature delivery, usually medically indicated for the benefit of the mother. This results in infant morbidity and substantial healthcare expenditure.4 Despite the considerable morbidity and mortality, the cause of preeclampsia has remained enigmatic. Both hypertension and proteinuria implicate the endothelium as the target of the disease. The hypertension of preeclampsia is characterized by peripheral vasoconstriction and decreased arterial compliance.5,6 The proteinuria of preeclampsia is associated with a pathognomonic renal lesion known as glomerular endotheliosis, in which the endothelial cells of the glomerulus swell and endothelial fenestrations are lost.7,8 Podocyturia has been recently associated with preeclampsia during clinical disease9; however, whether this is the cause or effect of proteinuria is unknown. The glomerular filtration rate is decreased compared with normotensive pregnant women; in rare cases, acute renal failure may develop. Preeclampsia is a systemic vascular disorder that may also affect the liver and the brain in the mothers. When the liver is involved, women may present with abdominal pain, nausea, vomiting, and elevated liver enzymes. Pathological examination of the liver reveals periportal and sinusoidal fibrin deposition and, in more extreme cases, hemorrhage and necrosis.10 The severe preeclampsia variant HELLP syndrome (hemolysis, elevated liver enzymes, low platelets) occurs in ≈20% of women with severe preeclampsia,11 and is named not only for the liver involvement, but also for the disorder of the coagulation system that develops.12 Approximately 20% of …

High fetal plasma adenosine concentration: a role for the fetus in preeclampsia?

Clinical observations suggest a role for the fetus in the maternal manifestations of preeclampsia, but the possible signaling mechanisms remain unclear. This study compares the fetal plasma concentrations of adenosine from normal pregnancies with those from preeclampsia. This secondary data analysis included normal pregnancies (n = 27) and patients with preeclampsia (n = 39). Patients with preeclampsia were subclassified into patients with (n = 25) and without (n = 14) abnormal uterine artery Doppler velocimetry (UADV). Fetal plasma concentrations of adenosine were significantly higher in patients with preeclampsia (1.35 ± 0.09 μmol/L) than in normal pregnancies (0.52 ± 0.06 μmol/L; P < .0001). Fetal plasma concentrations of adenosine in patients with preeclampsia with abnormal UADV (1.78 ± 0.15 μmol/L), but not with normal UADV (0.58 ± 0.14 μmol/L), were significantly higher than in normal pregnancies (P < .0001). Patients with preeclampsia with sonographic evidence of chronic uteroplacental ischemia have high fetal plasma concentrations of adenosine.

To Doppler or Not to Doppler: From Doppler Ultrasound to Color Doppler to Doppler in 3D and Beyond

ABSTRACT This review aims to provide the reader with an update on the present and potential clinical applications in Doppler ultrasound in perinatal medicine. Umbilical artery Doppler plays an important role in the management of intrauterine growth restriction (IUGR) and pre-eclampsia and aids in twin-to-twin transfusion syndrome management while notching in the waveform is a predictor of umbilical cord abnormalities. Middle cerebral artery Doppler reliably detects fetal anemia and may be useful in the assessment of IUGR as well. Abnormal uterine artery Doppler may play a role in predicting growth restriction, hypertensive disorders of pregnancy and preterm delivery. Abnormal ductus venosus waveforms can also be used to predict adverse fetal outcome and may allow for better timing of delivery while umbilical venous pulsations may be a sensitive marker for fetal heart failure in hydropic pregnancies. 3D power Doppler allows better small vessel visualization that is not affected by angle of insonation and has been used to diagnose placental and cord abnormalities. Significant improvements have recently occurred, improving the visualization and evaluation of placental vascularity, resulting from enhancements in delineation of tissue detail through electronic compounding and harmonics as well as enhancements in signal processing of frequency- and/or amplitude-based color Doppler ultrasound. Spatial representation of vascularity can be improved by utilizing 3D processing. Greater sensitivity of 3D Doppler ultrasound to macro- and microvascular flow has provided improved anatomic and physiologic assessment throughout pregnancy. The rapid development of these new ultrasound techniques will continue to enlarge the scope of clinical applications in placental studies. As clinical experience with these new technologies increases and as the technology improves further, it is reasonable to expect that 3D Doppler and 4D ultrasound will be complementary addition to well-established 2D Doppler ultrasound imaging.