Reproducibility and repeatability of transabdominal uterine artery Doppler velocimetry between 10 and 14 weeks of gestation

Regulation of stanniocalcin-1 secretion by BeWo cells and first trimester human placental tissue from normal pregnancies and those at increased risk of developing preeclampsia

Stanniocalcin-1 (STC-1) is a multi-functional glycosylated peptide present in the plasma of healthy women postpartum and increased further in pregnancies complicated by preeclampsia. Although the STC-1 gene is expressed by the placenta what regulates its secretion and from which cells at the feto-maternal interface is unknown. Here, we demonstrate for the first time that the syncytiotrophoblast and cytotrophoblast are a major site of STC-1 protein expression in first trimester placental tissue. Further, in response to low oxygen, first trimester chorionic villous tissue from pregnancies at increased risk of developing preeclampsia secreted significantly more STC-1 than normal tissue under the same conditions. Using the human trophoblast cell line BeWo we have shown that low oxygen increased the secretion of STC-1 but it required co-stimulation with the Adenosine-3', 5'-cyclic monophosphate (cAMP) analogue, 8-Bromo adenosine-3', 5'-cyclic monophosphate cAMP (8 Br-cAMP) to reach significance. Inhibition of Hypoxia inducible factor 2α (HIF-2α) and the Phosphatidylinositol-3 kinase (PI3 -Kinase)/AKT/Serum and glucocorticoid-induced kinase-1(SGK-1) pathway resulted in significant inhibition of STC-1 secretion. As both low oxygen and cAMP are known to play a central role in placental function, their regulation of STC-1 points to a potentially important role in the maintenance of a normal healthy pregnancy and we would hypothesize that it may act to protect against prolonged placental hypoxia seen in preeclampsia.

Newfangled Procedures Using X-ray to Determine the Cobb Angle in Patients with Scoliosis: An Updated Systematic Review

BACKGROUND

Scoliosis is a three-dimensional deformity of the spine. It is usually assessed by measuring Cobb angle. Nowadays, due to increasing effectiveness of image processing and machine vision, willingness to apply these methods has improved considerably in determining scoliosis of Cobb angle.

METHODS

In accordance with the PRISMA guideline, a broad electronic search of all English language literature was conducted on the topic through four databases, including MEDLINE, Web of Science, Scopus, and the Cochrane Library from 2012 (last search date from earlier review) to 30 March 2017.

RESULTS

Twelve studies were included. 90% labeled high-quality were selected for analysis. Eighty percent of the selected studies were published in the period between 2012 and 2017. Three new procedures were used to measure the Cobb angle. One study used automated procedure (7%), two studies used smartphone procedure (14%), and nine studies used the semiautomatic procedure of Cobb measurement (79%). Seven studies reported reproducibility and repeatability. Reproducibility range was 0.72 to 1 in reporting of ICC. Repeatability has a high range in three separated methods.

CONCLUSION

Computerized assessment method (Automatic and Semi-automatic) is most commonly performed in Cobb measurement. Semi-automatic is an effective measurement option for computerized assessment Cobb angle. There is no significant difference between manual, computer- based, and smartphone-based methods in described measures.

Inter- and intra-observer variability in fetal ductus venosus blood flow measurements in high-risk fetuses at 26-32 weeks

OBJECTIVES

Early preterm fetal growth restriction is a significant contributor to perinatal morbidity and mortality. The ductus venosus pulsatility index for veins (DV PIV) is proposed as a monitoring tool because it appears to improve perinatal outcomes. The test characteristics and robustness of DV PIV have been inadequately described. The aim of this study was to investigate inter- and intra-observer variability of DV PIV.

STUDY DESIGN

Nineteen women with a gestational age between 26 and 32 completed weeks were included in this study. Doppler sonographic fetal assessment was performed by two independent maternal-fetal medicine specialists. Each sonographer alternately performed three flow tracings for each participant, in the absence of the other sonographer (six tracings in total per patient). DV PIV was calculated automatically from stored tracings by a third researcher. Inter- and intra-observer variability of DV PIV and limits of agreement were assessed using the Bland-Altman method. Comparison of the distribution was performed with Kendall's related samples test, and the intraclass correlation coefficient (ICC) was calculated.

RESULTS

In total, 114 DV measurements were taken from 19 participants with a median age of 31 years [interquartile range (IQR) 26-34 years] at a median gestational age of 28 weeks (IQR 27-29 weeks). The proportional limits of agreement for intra-observer variation were -0.48 to 0.48 and -0.39 to 0.62 for the two observers. ICCs were 0.66 [95% confidence interval (CI) 0.42-0.84] and 0.68 (95% CI 0.45-0.85). The proportional limits of agreement for inter-observer variation were -0.29 to 0.19 with an ICC of 0.89 (95% CI 0.73-0.96).

CONCLUSION

Inter-observer variation was far less than intra-observer variation, probably due to mitigation of biological variation by averaging three measurements. DV PIV has acceptable test characteristics for use in a clinical setting when the average of at least three consecutive measurements is used.

Third trimester uterine artery Doppler indices as predictors of preeclampsia and neonatal small for gestational age

Objective: To test the hypothesis that third-trimester uterine artery Doppler (UAD) predicts adverse pregnancy and neonatal outcomes in a high-risk population.Study design: This is a nested case control study of women with singleton gestations referred for a fetal growth ultrasound between 24 and 36 weeks. Third-trimester UAD was performed if estimated fetal weight (Hadlock's chart) was <20th percentile as these patients were considered high risk for poor pregnancy outcomes. The primary outcomes assessed were neonatal small for gestational age (SGA) and hypertensive disorders. Secondary outcomes included pH <7.10, NICU admission, Apgar <7 at 5 minutes, respiratory distress syndrome, hypoglycemia, and a composite (presence of one or more of the secondary outcomes) neonatal adverse outcome. The sensitivity and specificity of the UAD indices for predicting these outcomes were compared.Results: Among 200 women included, neonatal SGA occurred in 91 (46%) neonates, preeclampsia in 21 (10.5%), early preeclampsia in 4 (2%) and a composite adverse outcome in 67 (34%) neonates. Abnormal UAD indices, specifically left uterine artery notching and pulsatile index (PI) >95th percentile, were significantly correlated with an increased relative risk (RR) of a number of outcomes. Left uterine artery notching was significantly associated with SGA, RR 1.76 (1.03-3.04), preeclampsia, RR 2.53 (1.47-4.37) and early preeclampsia, RR 2.88 (1.34-6.20). The PI >95th percentile was significantly associated with SGA, RR 1.83 (1.21-2.76), NICU admission, RR 1.79 (1.14-2.79), preeclampsia, RR 1.98 (1.29-3.03), and early preeclampsia, RR 3.13 (2.54-3.86). The mean UAD PI >95th percentile had the best sensitivity for SGA, but the area under the ROC curve (AUC) was modest (0.60, 95% CI = 0.53-0.67). Left uterine artery notching and PI >95th percentile had similar predictive utility for preeclampsia AUC 0.65, 95% CI = 0.53-0.76 (mean uterine artery PI >95th percentile) and AUC 0.66, 95% CI = 0.54-0.77 (left uterine artery notching).Conclusion: Abnormal third-trimester UAD indices are associated with adverse perinatal outcomes including neonatal SGA, preeclampsia, and early preeclampsia. Though statistically significantly correlated, the predictive value of UAD indices for adverse pregnancy and neonatal outcomes was modest.

First trimester placental endothelial cells from pregnancies with abnormal uterine artery Doppler are more sensitive to apoptotic stimuli

Failure of the placental capillary network to develop normally is associated with early onset fetal growth restriction (FGR) and pre-eclampsia (PE). Although the symptoms are observed at term, the problem begins in the first trimester. However, investigations at this clinically relevant time are hindered by difficulties in identifying earlystage pregnancies that are at risk of developing FGR/PE. Using uterine artery Doppler ultrasound in the first trimester as a proxy measure of poor placentation, we have identified pregnancies at increased risk of developing early onset FGR/PE. Placental endothelial cells (PEC) isolated from pregnancies at increased risk of developing FGR/PE grew more slowly and their basal rate of apoptosis was significantly higher than that seen in the normal group. The pro-apoptotic stimulus, TNFα, induced apoptosis in cells from both groups but this was significantly greater in the high risk group. TNF receptor expression was unaffected. Inhibition of nitric oxide (NO) production significantly increased the sensitivity of cells from the normal pregnancies to TNFα but not in the high risk group establishing a functional role for NO in this system. In conclusion, first trimester PEC from pregnancies at increased risk of developing early onset FGR/PE were inherently more sensitive to apoptotic stimuli and this was functionally linked to the synthesis of NO. This may contribute to the poor placental vascular development seen in on going pregnancies.

Measurement of cardiac function by cardiac time intervals, applicability in normal pregnancy and twin-to-twin transfusion syndrome

BACKGROUND

To detect early cardiac deterioration, a simple and stable tool is needed. Measurement of time intervals in a simple 4-chamber view using color-coded tissue Doppler imaging is a relatively new approach to assess fetal cardiac function. The aim of this study was to evaluate the applicability of this modality and to construct reference ranges for cardiac time intervals.

METHODS

We performed a prospective longitudinal cohort study in healthy fetuses. We used linear mixed models to construct age-adjusted reference ranges for shortening time (St) and lengthening time (Lt) in three cardiac regions: global heart and right and left ventricular wall. St and Lt were expressed as percentage of the cardiac cycle. Feasibility and intra- and interobserver variabilities were evaluated. We applied the technique to twin-twin transfusion syndrome (TTTS) recipients before laser therapy to test the diagnostic performance.

RESULTS

A total of 251 recordings were obtained from 54 healthy singletons. St decreased and Lt increased with gestational age in all regions. We found a high feasibility (99.6%) and excellent intra-/interobserver variability for St (0.96/0.94) and Lt (0.99/0.96) of the global heart. Left and right ventricle performance parameters were good. In TTTS recipients, St was prolonged (p < 0.01) and Lt was shortened (p < 0.01) in all regions and the feasibility was excellent (96.6%).

CONCLUSIONS

The assessment of fetal cardiac function by measurement of cardiac time intervals is technically feasible with good reproducibility, even in difficult scanning circumstances such as TTTS. It is possible to discriminate between healthy and compromised fetuses with this technique.

Decidual cell regulation of trophoblast is altered in pregnancies at risk of pre-eclampsia

Successful implantation and placentation are dependent on the interaction between decidual stromal cells (DSC) and extravillous trophoblast (EVT) cells. The extent of trophoblast invasion relies on communication between the placenta and maternal decidua. The cyclical process of decidualisation induces a transformation of endometrial fibroblasts to secretory DSC; these secreted products have many functions including the control of trophoblast invasion. Inadequate trophoblast invasion and remodelling of the uterine vessels (the spiral arteries) are associated with pregnancy disorders such as pre-eclampsia. Uterine artery Doppler resistance index (RI) in the first trimester of pregnancy can be used as a proxy measure of remodelling. DSC were isolated from pregnancies with normal (normal RI) or impaired (high RI) spiral artery remodelling. Following isolation, DSC were re-decidualised using cAMP and MPA and secretion of the decidualisation markers IGFBP-1 and prolactin assessed. We examined the impact of DSC-secreted factors on trophoblast cell function, using the EVT cell line SGHPL-4. We demonstrated that DSC exposed to decidual factors were able to re-decidualise in vitro and that the chemoattraction of trophoblasts by DSC is impaired in pregnancies with high RI. This study provides new insights into the role that DSC play in regulating EVT functions during the first trimester of pregnancy. This is the first study to demonstrate that DSC from pregnancies with impaired vascular remodelling in the first trimester secrete factors that inhibit the directional movement of trophoblast cells. This finding may be important in understanding aberrant trophoblast invasion in pregnancies where vascular remodelling is impaired.

Validation of Fetal Medicine Foundation algorithm for prediction of pre-eclampsia in the first trimester in an unselected Brazilian population

OBJECTIVE

The objective of this study is to evaluate the predictive performance of the Fetal Medicine Foundation (FMF) algorithm for prediction of preeclampsia (PE) between 11 and 14 weeks of gestation in an unselected Brazilian population.

METHODS

We conducted a prospective cohort study with 617 singleton pregnancies of unselected risk. Biophysical markers (mean pulsatility index, mean arterial pressure) and biochemical markers (placental growth factor (PLGF) and PAPP-A) were inserted into the FMF software and converted into multiples of the median (MoM). The subjects were divided into five groups: early-onset PE, parturition <34 weeks' gestation; preterm PE, parturition <37 weeks; PE, parturition at any gestational age; gestational hypertension (GH); and control group. Areas under the receiver operating characteristics curve (AUC) were calculated for the outcomes.

RESULTS

Among 617 patients, seven developed early-onset PE, 18 developed preterm PE (seven early PE plus 11 delivered between 34 and 36 + 6 weeks gestation), 34 developed PE (18 preterm PE plus 16 delivered after 37-week gestation), 12 pregnant women developed GH, and 517 women comprised the control group. The best predictive performance using the FMF algorithm occurred in the early-onset PE group, with AUC = 0.946 (95% CI 0.919-0.973) and the detection rate of 28.6% and 85.7% for 5% and 10% false-positive (FP), respectively.

CONCLUSIONS

The FMF algorithm to predict PE was effective in a Brazilian population, mainly in the early-onset form of the disease at 10% FP.

Beat-to-beat variability of fetal myocardial performance index

OBJECTIVES

To determine whether there is beat-to-beat (BTB) variability in the fetal left myocardial performance index (MPI), as evaluated by an automated system, and whether there is a correlation between MPI and fetal heart rate (FHR).

METHODS

This was a prospective cross-sectional study of uncomplicated, morphologically normal, singleton pregnancies at 20-38 weeks' gestation. Multiple cineloops for left MPI measurement were acquired during a single examination of each fetus. Raw cineloop data were analyzed by our automated MPI system (intraclass correlation coefficient of 1.0 for any given waveform) to produce a set of MPIs. The corresponding instantaneous FHR was measured for each individual cardiac cycle for which MPI was calculated.

RESULTS

Data from 29 fetuses were analyzed; mean MPI was 0.52, mean FHR was 150 beats per min and the median number of cardiac cycles examined per fetus was 70 (interquartile range, 31-115). Marked BTB variability was noted; median coefficient of variation was 10% (range, 5.5-13.9%). FHR was weakly correlated with absolute MPI (r = 0.22; P < 0.05). BTB variation in MPI as a percentage of the mean MPI was not significantly correlated with FHR (r = 0.031; P = 0.146). When standard error of the mean of all MPI values was divided by the mean for each case, it showed that at least four cardiac cycles should be averaged to reduce MPI variability to approximately ± 5%.

CONCLUSION

There is significant BTB variability in fetal left MPI, which has an overall weak correlation with FHR. This could be a factor affecting the consistency of MPI values reported by different research groups. Variability would be reduced by averaging 4-5 cardiac cycles per fetus. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

The role of decidual NK cells in pregnancies with impaired vascular remodelling

The pathologies of the dangerous pregnancy complications pre-eclampsia (PE) and fetal growth restriction (FGR) are established in the first trimester of human pregnancy yet we know little of how this happens. Finely tuned interactions between maternal and placental cells are essential for pregnancy to progress without complications; however, the precise nature of this cross-talk and how it can go wrong are crucial questions that remain to be answered. This review summarises recent studies examining the role played by natural killer cells in regulating normal placentation and remodelling. Their involvement when it is impaired in PE/FGR pregnancies will additionally be discussed.

Second-Trimester 3-Dimensional Placental Sonography as a Predictor of Small-for-Gestational-Age Birth Weight

OBJECTIVES

We previously reported the association between first-trimester 3-dimensional (3D) placental measurements and small-for-gestational-age (SGA) neonates. In this study, we sought to determine whether second-trimester measurements further contribute to the antenatal detection of SGA and preeclampsia.

METHODS

We prospectively collected 3D sonographic volume sets and uterine artery pulsatility indices of singleton pregnancies at 18 to 24 weeks. Placental volume, placental quotient (placental volume/gestational age), mean placental diameter and chorionic diameter, placental morphologic index (mean placental diameter/placental quotient), placental chorionic index (mean chorionic diameter/placental quotient), and placental growth (volume per week) were assessed and evaluated as predictors of SGA and preeclampsia as a composite and alone.

RESULTS

Of 373 pregnancies, the composite outcome occurred in 67 (18.0%): 36 (9.7%) manifested SGA alone; 27 (7.2%) developed preeclampsia alone, and 4 (1.1%) developed both. The placental volume, placental quotient, mean placental diameter, mean chorionic diameter, and volume per week were significantly smaller, whereas the placental morphologic index and chorionic index were significantly larger in pregnancies with the composite outcome (P < .01). Further analyses revealed that the significant associations with placental parameters were limited to the SGA outcome. Each placental measure remained significantly associated with SGA after adjusting for confounders. The mean uterine artery pulsatility index was not associated with either outcome. Placental parameters were moderately predictive of SGA, with adjusted areas under the curve ranging from 0.72 to 0.76. Sensitivity for detection of SGA ranged from 32.5% to 45.0%, with positive predictive values ranging from 17.3% to 22.7%.

CONCLUSIONS

Second-trimester 3D placental measurements can identify pregnancies at risk of SGA. However, there appears to be no significant improvement compared to those obtained in the first trimester.

Digital auscultation of the uterine artery: a measure of uteroplacental perfusion

This observational study investigated digital auscultation for the purpose of assessing the clinical feasibility of monitoring vascular sounds in pregnancy. The study was performed at the Regional Hospital Viborg, Denmark, and included 29 pregnant women, 10 non-pregnant women and 10 male participants. Digital auscultation was performed with an electronic stethoscope bilaterally near the uterine arteries and correlated to the clinical diagnosis of preeclampsia (PE), intrauterine growth restriction (IUGR) or normal pregnancy in the group of pregnant participants. In the group of non-pregnant participants, digital auscultation was performed as control measurements in the same anatomical positions. The auscultations displayed pulse waveforms comprising systolic and diastolic periods in 20 of the 29 pregnant participants. However, in the non-pregnant and male participants, the pulse waveforms were absent. The pulsatile patterns are thus likely to originate from the arteries in relation to the pregnant uterus. In the participants displaying pulse waveforms, the presence of a dicrotic notch appeared with a sensitivity of 89% and a specificity of 100% in the discrimination of normal pregnancies (n  =  11) from pregnancies with PE or IUGR (n  =  9), (p  <  0.001). This preliminary study shows the potential of identifying vascular complications during pregnancy such as preeclampsia and intrauterine growth restriction. The morphology of the derived pulse contour should be investigated and could be further developed to identify pathophysiology.

Postpartum uterine artery blood flow impedance following cesarean section or vaginal delivery

PURPOSE

To compare uterine arteries (UtA) blood flow after cesarean section (CS) or vaginal delivery (VD).

METHODS

We performed a prospective case-control study comparing UtA blood flow impedance in patients who delivered by CS or VD. The UtA pulsatility index (PI) was measured with Doppler ultrasound during post partum using a transabdominal convex probe. Maternal and gestational age, parity, gravidity, and delay between delivery and Doppler measurement were noted.

RESULTS

We examined 106 postnatal patients, of whom 35 had CS delivery and 71 had VD. The median delay from delivery to Doppler measurement was 35 hours for the CS group and 32 hours for the VD group. The mean PI following CS and VD was 1.62 ± 0.45 and 1.42 ± 0.47, respectively. Using a linear model, the regression coefficients for mean, right, and left PI were not significantly different depending on the mode of delivery. There was no difference between emergency and elective CS.

CONCLUSIONS

Early postpartum UtA blood flow impedance is not significantly different after CS or VD. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 44:278-283, 2016.

Reproducibility of first- and second-trimester uterine artery pulsatility index measured by transvaginal and transabdominal ultrasound

OBJECTIVES

To examine and compare the reproducibility of measurement of first- and second-trimester uterine artery pulsatility index (UtA-PI) using transabdominal (TAS) and transvaginal (TVS) ultrasound.

METHODS

This was an observational study including women ≥ 18 years of age, with a singleton pregnancy, in the first trimester (between 11 + 0 and 13 + 6 weeks' gestation) or second trimester (between 20 and 26 weeks' gestation). UtA-PI and angle of insonation were assessed by two observers (one with 15 and the other with 3 years of experience) using both TAS and TVS. The more experienced observer performed two scans alternated by the other observer. The acquisitions were completely independent and the observers were blinded to each other and to their own measurements. Reproducibility of the measurements by TVS and TAS was assessed using the concordance correlation coefficients (CCCs), intraclass correlation coefficients (ICCs) and limits of agreement (LoA).

RESULTS

We analyzed data from 97 women in the first trimester and 96 in the second trimester. The mean ± SD UtA-PI was significantly higher when measured using TVS, compared with TAS, in both the first (1.60 ± 0.49 vs 1.52 ± 0.63, respectively; P = 0.03) and second (1.07 ± 0.33 vs 0.96 ± 0.32, respectively; P < 0.001) trimesters. The median angle of insonation was significantly lower when using TVS, compared with TAS, in both the first (8.0° (interquartile range (IQR), 2.5-16.3°) vs 12.5° (IQR, 2.5-20.0°), respectively; P = 0.04) and second (10.0° (IQR, 4.5-16.5°) vs 17.5° (IQR, 5.0-27.9°), respectively; P < 0.001) trimesters. Both ultrasound techniques had similar reproducibility: the intraobserver CCC ranged from 0.93 to 0.95 and the interobserver CCC ranged from 0.81 to 0.86; and the ICCs of both techniques were highly comparable (the intraobserver LoA was approximately ± 20-30% and the interobserver LoA was approximately ± 30-40%).

CONCLUSIONS

When measuring UtA-PI, assessment by TVS provides higher values and better insonation angle compared with TAS. The reproducibility of the ultrasound methods in both first and second trimesters of pregnancy was comparable and should not be considered as good. Future studies examining technical improvements with the aim of increasing the reproducibility of this technique should be encouraged.

β-Blocker therapy ameliorates hypersplenism due to portal hypertension in children

BACKGROUND/PURPOSE

Thrombocytopenia due to hypersplenism precludes percutaneous liver biopsy in many cases of chronic liver disease (CLD). The aim of this study was to assess the efficacy of propranolol in correcting platelet counts (>100,000/mm(3)) to ensure percutaneous liver biopsy in children with CLD.

METHODS

From January 2005 to December 2012, 51 consecutive children (mean age 11.5 ± 3.0 years, 34 boys) with CLD who needed liver biopsy but could not be done due to hypersplenism-related thrombocytopenia (platelets <100,000/mm(3) and/or total leukocyte counts <4,000/mm(3) with splenomegaly) were recruited and given a 4-week trial of long-acting propranolol (1.5-2 mg/kg/day). Hemodynamic parameters and splenic artery hemodynamics by Doppler ultrasound were recorded before and after the propranolol trial. Response to therapy was defined as improvement of platelet counts to ≥10(5)/mm(3).

RESULTS

Thirty-two (62.7%) children responded to propranolol therapy and their mean platelet counts increased from 57.5 ± 13.0 × 10(3) to 140.7 ± 43.3 × 10(3)/mm(3), p = 0.0001. Liver biopsy could be done in 29. While comparing responders with non-responders, baseline spleen size (7.4 ± 3.3 vs. 12.7 ± 4.5 cm, p = 0.0001) and platelet counts (57.5 ± 13.0 × 10(3) vs. 39.5 ± 14.5 × 10(3), p = 0.0001) were found to be significant. ROC curve suggested a cut-off value of ≤8.5 cm of spleen and ≥53,000 platelets as predictors of response. With propranolol, mean arterial pressure and spleen size reduced (p < 0.05) and splenic artery resistance increased significantly (p = 0.005) in responders.

CONCLUSIONS

Propranolol corrects thrombocytopenia and makes liver biopsy possible in almost two-thirds of cases by reducing splenic sequestration through splenic artery vasoconstriction. The baseline spleen size and platelet counts determine the effectiveness of therapy. A trial of β-blocker is worth carrying out in cases where liver biopsy is contraindicated due to hypersplenism-related thrombocytopenia.

Angiogenic factors and uterine Doppler velocimetry in early- and late-onset preeclampsia

OBJECTIVE

To assess correlations between maternal serum levels of pro- and anti-angiogenic factors with uterine perfusion in women with early- compared with late-onset preeclampsia, and in healthy pregnant women.

DESIGN

Case-control study.

SETTING

Antenatal care clinic located within a hospital (São Bernardo do Campo, Brazil).

POPULATION

We enrolled 54 preeclamptic and 54 healthy control women who were coming for routine ultrasound at 28-36 weeks' gestation.

METHODS

All participants had uterine artery and umbilical Doppler studies and a blood sample to assess maternal serum levels of soluble fms-like tyrosine kinase-1, soluble endoglin, adiponectin and plasminogen activator inhibitor-1. All angiogenic factors were measured using enzyme-linked immunosorbent assay.

MAIN OUTCOME MEASURES

Levels of pro- and anti-angiogenic factors in maternal serum, and uterine artery Doppler findings.

RESULTS

Concentrations of soluble fms-like tyrosine kinase-1 and soluble endoglin were significantly higher in preeclamptic than control women (p < 0.0001 and p < 0.0001, respectively), especially in those with early-onset (<34 weeks) preeclampsia. These two anti-angiogenic mediators were significantly correlated with increased uterine artery Doppler in the preeclamptic women. Plasminogen activator inhibitor-1 levels were significantly higher in preeclampsia (p = 0.03) but unrelated to uterine artery resistance. Adiponectin levels were similar in cases and controls, independent of body mass index and unrelated to uterine artery resistance.

CONCLUSION

Preeclamptic patients have increased soluble fms-like tyrosine kinase-1 and soluble endoglin serum levels and this increase is directly correlated with uterine artery resistance, especially in those with early-onset preeclampsia.

Comparison of two different sites of measurement for transabdominal uterine artery Doppler velocimetry at 11-13 weeks

OBJECTIVES

To compare the feasibility of two transabdominal approaches for performing first-trimester uterine artery (UtA) Doppler and to evaluate the correlation with pulsatility index (PI) in the second trimester.

METHODS

This was a prospective longitudinal Doppler study of the uterine arteries at 11-13 and 21-22 weeks' gestation. Transabdominal ultrasound and color Doppler were used to measure the UtA-PI of the ascending branch of the uterine artery at the level of the internal cervical os (Site A) and at the level of the apparent crossover with the external iliac artery (Site B) at 11-13 weeks, and at Site B only at 21-22 weeks. In all cases the measured left and right PI were converted to a multiple of the median (MoM) for gestational age, and the intercorrelation between the measurements at different sites and gestational ages was calculated using non-parametric analysis (Spearman's rank correlation).

RESULTS

Satisfactory measurements were obtained at 11-13 weeks from both uterine arteries in all 81 women at Site A and in 50 (62%; 95% CI, 50-72%) at Site B (P < 0.01). Measurements were obtained at Site B at 21-22 weeks in all cases. In the 50 cases with measurements from both sites at 11-13 weeks, the correlation of PI-MoMs between Sites A and B at 11-13 weeks was only moderate (ρ = 0.61). The correlation between first-trimester UtA-PI MoMs at Site A and second-trimester UtA-PI MoMs was stronger than that between first-trimester UtA-PI MoMs at Site B and second-trimester UtA-PI MoMs (ρ = 0.73 vs ρ = 0.47, P < 0.01).

CONCLUSION

Evaluation of UtA-PI at 11-13 weeks can be achieved at the level of the internal cervical os in a greater proportion of women than at the level of the apparent crossover with the external iliac vessels, and the measurements obtained correlate better with second-trimester UtA-PI.

Imaging and assessment of placental function

The placenta is the vital support organ for the developing fetus. This article reviews current ultrasound (US) methods of assessing placental function. The ability of ultrasound to detect placental pathology is discussed. Doppler technology to investigate the fetal, placental, and maternal circulations in both high-risk and uncomplicated pregnancies is discussed and the current literature on the value of three-dimensional power Doppler studies to assess placental volume and vascularization is also evaluated. The article highlights the need for further research into three-dimensional ultrasound and alternative methods of placental evaluation if progress is to be made in optimizing placental function assessment.

Sensitivity of higher, lower and mean second-trimester uterine artery Doppler resistance indices in screening for pre-eclampsia

OBJECTIVES

First-trimester Doppler studies have reported that the lower uterine artery (UtA) resistance index (RI) is better for the prediction of pre-eclampsia (PE) than is either the mean or higher indices. The aim of this study was to determine if this relationship is true in the second trimester.

METHODS

This was a retrospective study of 24 859 singleton pregnancies. During the study period second-trimester UtA Doppler assessment was routinely available to all nulliparous women and to parous women at increased risk of PE. UtA-RI was obtained at the time of the anomaly scan. Receiver-operating characteristics curves for the lower, mean and higher UtA-RI for the prediction of PE were calculated.

RESULTS

There were 1037 cases of PE. There were significant associations between UtA-RI and PE, the association being stronger for early and preterm than late or term PE. There was no significant difference in the strength of the association between lower, mean and higher RI with PE at any gestation.

CONCLUSION

Performance of UtA-RI in predicting PE is no different for the lower, higher or mean RI of the two UtAs. The most likely explanation for the discrepancy with first-trimester studies is that the placental-side effect on Doppler indices may change with advancing gestational age and progressive trophoblast development and invasion.

First-trimester assessment of placenta function and the prediction of preeclampsia and intrauterine growth restriction

Preeclampsia and intrauterine growth restriction (IUGR) are major contributors to perinatal mortality and morbidity worldwide. Both are characterized by impaired trophoblastic invasion of the maternal spiral arteries and their conversion from narrow muscular vessels to wide non-muscular channels. Despite improvement in the understanding of the pathophysiology of these conditions, ability to accurately identify pregnant woman who will develop them is limited. This greatly impairs the development and testing of preventive interventions. While different measures of placental dysfunction have been associated with increased risk for adverse pregnancy outcomes, the ability of any single one to accurately predict these outcomes is poor. Developing predictive tests is further challenged by difficulty in the timing of the measurements, as both the structural and biochemical characteristics of the placenta change with increasing gestational age. The ideal screening test would accurately predict the development of adverse pregnancy outcomes early enough to provide a window for preventive interventions. Improvement in ultrasound technology provides potentially useful novel tools for evaluating placental structure, but measurements need to be standardized in order to be useful. Maternal serum analyte screening is a noninvasive test of placental biochemical function, but present serum marker alone is not sufficiently accurate to suggest its routine use in clinical practice. The use of first trimester biochemical markers in combination with uterine artery Doppler screening is promising as a potential screening tool. Prospective longitudinal studies using standardized methodology are necessary to further evaluate the choice of parameters and strategies of combination to achieve the best predictive models.

Circulating levels of matrix proteases and their inhibitors in pregnant women with and without a history of recurrent pregnancy loss

BACKGROUND

We have recently shown that serum relaxin-2 levels are attenuated in women with a history of recurrent pregnancy loss (RPL). We sought to determine whether a history of RPL is also associated with changes in serum matrix metalloproteases (MMPs) and tissue inhibitors of matrix metalloproteases (TIMP) -1 and -2.

METHODS

We obtained serum from 20 pregnant women with a history of RPL and 20 age-matched pregnant women with no history of RPL (NRPL) at 6-8, 10-12, 20, and 34 weeks gestation, and from cord blood. We quantified total serum concentrations of MMP-1, MMP-3, MMP-9 and TIMP-1 and TIMP-2 by ELISA. We determined whether these serum marker levels were associated with a history of RPL and delivery before 37 weeks gestation.

RESULTS

There was no difference in the rates of miscarriage, preterm birth or prelabour rupture of fetal membranes between RPL and NRPL. However babies born to RPL were lighter than those born to NRPL. Serum MMP-1, 9, and TIMP-1 did not differ between RPL and NRPL but MMP-3 was higher in RPL vs. NRPL at 6-8 weeks (P < 0.05). Serum TIMP-2 levels were higher in RPL women at all gestations (P < 0.01). The ratio of RLX-2 (reported previously) to TIMP-2 at 10-12 weeks gestation was more strongly associated with a history of RPL than either peptide separately - area under the ROC curves for RLX-2 0.79 (95% CI 0.57 to 0.92), TIMP-2 0.83 (95% CI 0.63 to 0.95), and for RLX-2:TIMP-2 ratio 0.92 (95% CI 0.74 to 0.99).

CONCLUSIONS

Women with a history of RPL demonstrate increased serum TIMP-2 and reduced RLX-2 during a subsequent viable pregnancy. Determination of both markers in early pregnancy enhances the discrimination of women with a history of RPL. These observations suggest roles for these two peptides in early implantation and placental development. Whether these may prove to be reliable early predictive markers for subsequent pregnancy loss in the index pregnancy is unknown and will require further studies.

Índices de resistência e pulsatilidade das artérias uterinas no primeiro e segundo trimestres de gestações normais

OBJETIVO: Determinar os índices de resistência (IR) e pulsatilidade (IP) nas artérias uterinas durante o primeiro e segundo trimestres de gestação. MATERIAIS E MÉTODOS: Realizamos estudo prospectivo longitudinal em 44 mulheres normais, da 8ª a 12ª e na 22ª semanas de gestação. A dopplervelocimetria foi realizada em ambas as artérias uterinas por meio do IR e do IP. Utilizamos volume de amostra de 1 a 2 mm, filtro de 50 a 70 Hz e ângulo de insonação abaixo de 60°. RESULTADOS: O IR e o IP da artéria uterina no primeiro trimestre foram maiores da 8ª a 12ª do que na 22ª semana de gestação. O IR e o IP da artéria uterina, no primeiro trimestre, com incisura foram de 0,83 ± 0,07 e 2,32 ± 0,79, e sem incisura, de 0,71 ± 0,16 e 1,61 ± 0,78, respectivamente. No segundo trimestre, o IR e o IP da artéria uterina com incisura foram de 0,59 ± 0,09 e 1,03 ± 0,32, e sem incisura, de 0,44 ± 0,09 e 0,63 ± 0,19, respectivamente. CONCLUSÃO: Estabelecemos os valores de referência do IR e do IP das artérias uterinas de gestantes normais no primeiro e segundo trimestres de gestação.

Investigation of mammary blood flow changes by transrectal colour Doppler sonography in anEscherichia colimastitis model

The objectives of this preliminary investigation were to evaluate the feasibility of transrectal colour Doppler sonography (TCDS) for determining blood flow of the pudendoepigastric trunk in cows with experimentally inducedEscherichia coliMastitis. Five primiparous Holstein dairy cows, 4–6 months after calving, were examined in two trials. All monitored udder quarters were initially clinically healthy, somatic cell count (SCC) was <50 000 cells/ml and bacteriologically negative. The blood flow of the left and the right pudendoepigastric trunk was described by the blood flow volume (BFV). In the methodological part of the study, the intra-observer precision of the method was evaluated. The coefficients of variation of the BFV were 7·1% for the left and 9·4% for the right pudendoepigastric trunk. The intraclass correlation coefficients of the BFV were 0·99 (P<0·001) for the left and 0·75 (P=0·004) for the right vessel. BFV did not differ significantly between the left and the right side nor between pre- and post-milking nor between oestrus and dioestrus. In the experimental part of the study, significant differences of increasing BFV between 0 and 12 h p.i. (post infectionem) (P=0·043) and decreasing BFV between 12 and 24 h p.i. (P=0·043) were discovered for the pudendoepigastric trunk of the infected right side. In the left-right (control-infection) comparison a significant increase of the right BFV was observed at 12 h p.i. (P=0·043). The difference of an increasing SCC correlated positively with the difference of an increasing BFV between 0 and 12 h p.i. (Spearman's ρ=1·00;P=0·043) for the right infected side. It was shown that TCDS is a reproducible technique for investigating pathological mammary blood flow changes at an early stage of acute mastitis.

Reproducibility and repeatability of measuring the electrical impedance of the pregnant human cervix-the effect of probe size and applied pressure

Background

The utility of cervical electrical impedance spectroscopy (EIS) as a diagnostic tool is being investigated in clinical trials. We sought to assess the reliability of two different sizes of tetrapolar probes used in measuring cervical impedance.

Methods

Cervical transfer impedance was measured at 14 frequencies between 76 and 625 000 Hz from 11 pregnant subjects at term. Repeated measurements were taken with two probes (3 mm and 12 mm diameter) applied softly (approximately 0.7 Newton of force), and firmly (approximately 2.2 Newton) to the surface of the cervix by two observers. The intra-class correlation coefficient (ICC), coefficient of variation (CV) and repeatability standard deviations (SD) were derived from these measurements and compared.

Results

Measurements taken by one observer were highly repeatable for both probes as demonstrated by high ICC and low CV values. Probe performance was improved further by firm application. Firm application of the 3 mm probe resulted in ICC values that ranged from 0.936 to 0.986 (p = 0.0001) and CV values between 1.0 and 3.4%. Firm pressure with the 12 mm probe resulted in ICC values that ranged between 0.914 and 0.988 (p = 0.0001) with CV values between 0.7 and 2.1%. In addition, the repeatability SD was low across all frequencies implying that there was low intra-observer variability. Measurements taken by 2 observers with firm application of the 12 mm probe demonstrated moderate reproducibility between 9.8 and 156 kHz, the frequency range in which previous clinical studies have shown predictive association between high cervical resistivity and vaginal delivery: ICC values ranged between 0.528 and 0.638 (p < 0.05), CV values were between 3.3 and 5.2% and reproducibility SD values were also low. In contrast the 3 mm probe demonstrated poor reproducibility at all study frequencies.

Conclusion

Measuring cervical resistivity by a single observer with both the 3 and 12 mm probes is highly repeatable whilst inter-observer reproducibility is poor with the 3 mm probe but moderately good when the 12 mm probe is firmly applied to the cervix in the frequency range 9.8 to 156 kHz, consistent with our observations of probe performance in clinical trials.

First-trimester uterine artery Doppler indices in the prediction of small-for-gestational age pregnancy and intrauterine growth restriction

OBJECTIVES

To assess the relationship of first-trimester uterine artery Doppler indices with subsequent delivery of small-for-gestational age (SGA) neonates or intrauterine growth restriction (IUGR).

METHODS

This was a prospective study in which uterine artery Doppler assessment was performed at 11-14 weeks in 3010 women with singleton pregnancies. Resistance indices (RI) and incidence of bilateral notching were compared between women with normal pregnancies (n = 2445) and those who delivered: SGA neonates (birth weight < 10th centile) (n = 377); SGA neonates who had been affected by pre-eclampsia (n = 27); IUGR neonates (birth weight < 10th centile and abnormal Doppler indices) with delivery > or = 37 weeks (n = 62); and IUGR neonates requiring preterm delivery (delivery < 37 weeks) (n = 36).

RESULTS

The first-trimester uterine artery mean RI and prevalence of bilateral notching were significantly higher in women destined to deliver SGA neonates than in women with normal pregnancies (median uterine artery RI, 0.74 vs. 0.70, P < 0.001; prevalence of bilateral notches, 56% vs. 43%, P < 0.001). The areas under the receiver-operating characteristics curves for the prediction of SGA without pre-eclampsia, IUGR, preterm IUGR and SGA with pre-eclampsia were 0.602, 0.687, 0.776 and 0.708, respectively. There was a statistically significant inverse relationship between mean uterine artery RI and gestational age at delivery in the SGA pregnancies without pre-eclampsia (R = - 0.329, P = 0.01).

CONCLUSIONS

There is a significant relationship between first-trimester uterine artery Doppler RI and the subsequent development of SGA. The sensitivity of first-trimester uterine artery Doppler is greater for SGA with pre-eclampsia than it is for IUGR alone. This could be because these two entities may have different underlying placental abnormalities that are detected variably on first-trimester uterine artery Doppler evaluation.

First-trimester uterine artery Doppler indices in term and preterm pre-eclampsia

OBJECTIVES

To assess the relationship between first-trimester uterine artery Doppler measurements and the development of term and preterm pre-eclampsia.

METHODS

This prospective study of uterine artery Doppler findings at 11-14 weeks in 3058 singleton pregnancies included 57 and 33 cases of term and preterm pre-eclampsia, respectively.

RESULTS

The first-trimester uterine artery resistance index (RI) was significantly higher in women who subsequently developed preterm pre-eclampsia (mean RI, 0.79) than in those with a normal outcome (mean RI, 0.70; P = 0.0001) or those who developed pre-eclampsia at term (mean RI, 0.72; P = 0.002). There were no significant differences in first-trimester mean uterine artery RI (P = 0.136) or prevalence of bilateral notches (P = 0.459) between women who had a normal pregnancy outcome and those who developed pre-eclampsia at term. The receiver-operating characteristics curves for the prediction of term and preterm pre-eclampsia by uterine artery Doppler imaging demonstrated a significant association with development of preterm pre-eclampsia (P = 0.0001; area under the curve (AUC), 0.76; 95% CI, 0.66-0.86) but not term pre-eclampsia (P = 0.25; AUC, 0.54; 95% CI, 0.46-0.63).

CONCLUSIONS

The uterine artery Doppler data in this study suggest that preterm pre-eclampsia is strongly associated with defective invasion of the spiral arteries, in contrast to the findings in term pre-eclampsia which may be a consequence of placental deterioration at term. Our study findings support, but do not prove, a rigid separation between the etiology of early- and late-onset pre-eclampsia. Although there is a strong relationship between first-trimester uterine artery Doppler indices and the subsequent development of preterm pre-eclampsia, our data do not support its routine introduction into clinical practice.

First-trimester uterine artery resistance and maternal serum concentration of asymmetric dimethylarginine

OBJECTIVE

Maternal serum levels of asymmetric dimethyl-arginine (ADMA), an endogenous inhibitor of endothelial nitric oxide synthase, are known to be increased in pregnant women with high-resistance placental circulation in the second trimester. The aim of the present study was to investigate the relationship between uterine artery resistance and maternal serum ADMA concentrations in the first trimester.

METHODS

Doppler ultrasound examination of the maternal uterine arteries was performed at 10-14 weeks' gestation. High resistance was defined as bilateral uterine artery notches and a mean resistance index > 95th centile. Control cases were defined as those presenting with no notches and a mean resistance index < 95th centile. ADMA concentrations were measured in maternal serum.

RESULTS

Forty singleton pregnancies were examined, 21 with high uterine artery resistance and 19 controls. Three cases of pre-eclampsia occurred, all in the high-resistance group. The mean (SD) maternal serum ADMA concentration was 0.78 (44%) and 0.93 (56%) micromol/L in the high-resistance and control groups, respectively (P = 0.17). There was no statistically significant correlation between maternal serum ADMA and uterine artery resistance index (rho = - 0.15, P = 0.36).

CONCLUSIONS

No significant difference was found in maternal serum ADMA between pregnancies with first-trimester high-resistance uterine artery blood flow and controls. While second-trimester circulating ADMA may have a direct link with maternal endothelial function, in the first trimester the effect of ADMA may be mainly evident at the placental level, without consequently affecting maternal circulating concentrations of the substance.

Doppler examination of uteroplacental circulation in early pregnancy: can it predict adverse outcome?

PURPOSE

To determine whether spectral Doppler measurements obtained from bilateral uterine, arcuate, radial, and spiral arteries in early gestation correlate with adverse pregnancy outcome.

METHODS

One hundred five pregnant women underwent transvaginal Doppler sonographic examination of uteroplacental circulation at 6-12 weeks' gestation. Resistance index (RI) and pulsatility index (PI) of bilateral uterine, arcuate, radial, and spiral arteries were measured. Diameters of gestational sac (GS) and yolk sac, crown-rump length (CRL), GS-CRL difference, and GS/CRL ratio were also recorded. Correlation was made with pregnancy outcome.

RESULTS

Sixteen women developed adverse pregnancy outcome. In these women, right uterine artery PI and RI were significantly higher than in women with normal obstetrical outcome. Spiral artery PI and RI values were also higher, but the difference was not statistically significant. GS-CRL difference, GS/CRL ratio, and yolk sac diameters were significantly lower in this group.

CONCLUSION

Transvaginal Doppler examination can detect hemodynamic changes in uteroplacental circulation associated with subsequent adverse pregnancy outcome.

Increased apoptosis in first trimester extravillous trophoblasts from pregnancies at higher risk of developing preeclampsia

Preeclampsia complicates 5 to 10% of pregnancies and is a leading cause of maternal and fetal mortality and morbidity. Although the cause is unknown, inadequate invasion and remodeling of maternal uterine arteries by extravillous trophoblasts (EVTs) in the first trimester is a common feature. Uterine spiral artery resistance as detected by Doppler ultrasound is commonly used in the second trimester to identify pregnancies destined to develop preeclampsia. Correlation between high uterine resistance and the failure of trophoblast invasion has been reported as early as 12 weeks. However, the reason for this failure has not been established. Understanding the processes involved would significantly improve our diagnostic potential. In this study, we correlated increased first trimester uterine artery resistance with a biological abnormality in trophoblast function. EVTs derived from high-resistance pregnancies were more sensitive to apoptotic stimuli than those from normal-resistance pregnancies. Survival of EVTs from high-resistance pregnancies could be increased by nitric oxide, whereas inhibition of nitric oxide in cells from normal-resistance pregnancies increased apoptotic sensitivity. This predates the onset of symptoms by several weeks and provides evidence for a mechanism responsible for the incomplete uterine vessel remodeling and the differences in artery resistance between preeclamptic and normal pregnancies.

Uterine artery Doppler velocimetry at 11-14 weeks in singleton pregnancies conceived by assisted reproductive technology

OBJECTIVE

Singleton pregnancies resulting from assisted reproductive technologies (ART) have an increased risk of preterm delivery, pre-eclampsia and intrauterine growth restriction. The aim of the present study was to determine whether first-trimester trophoblastic invasion, as assessed by uterine artery Doppler velocimetry, is different in singleton pregnancies resulting from ART compared to those conceived naturally.

METHODS

Case-control study on 31 singleton ART pregnancies (26 in-vitro fertilization-embryo transfer, five intracytoplasmic sperm injection) and 62 matched pregnancies conceived spontaneously. Doppler velocimetry was performed at 11-14 weeks of gestation.

RESULTS

The mean resistance index (coefficient of variation) was 0.70 (17%) and 0.70 (18%) in ART and controls, respectively (P = 0.92). The corresponding values for mean pulsatility index were 1.40 (44%) and 1.47 (44%) in ART and controls, respectively (P = 0.58). Pregnancies with no, unilateral or bilateral diastolic notches were 48%, 26%, 26% and 36%, 37%, 27%, in ART and controls, respectively (P = 0.43).

CONCLUSION

There are no differences in uterine artery Doppler indices between pregnancies obtained by invasive ART and naturally conceived matched controls. This finding suggests that there is no major difference in trophoblastic invasion of the maternal spiral arteries between ART and spontaneous pregnancies.

The significance of uterine notching in Doppler sonography in early pregnancy as a predictor for pathologic outcome of the pregnancy

INTRODUCTION

Doppler sonography of maternal vessels as a predictor for preeclampsia is an established screening method in the second trimester. Considering the first trimester its benefit has not been conclusively proven so far. Up to now the flow pattern of maternal vessels in the first trimester has only been insufficiently characterized and documented. Thus, there are only few pieces of information concerning the predictive value of the different kinds of flow patterns during the early pregnancy as regards the pathological and physiological outcome of the pregnancy. This survey aimed at evaluating the significance and the clinical importance of Doppler sonographical examinations of the Aa. uterinae during early pregnancy. It had to be analyzed whether various perfusions can be applied as a predictive value for the specific development during the pregnancy and whether therefore a risk group for pregnancy-associated hypertension can already be detected during the early pregnancy.

MATERIALS AND METHODS

A non-selected collective of 104 pregnant patients was examined with Doppler sonography and retrospectively divided into a standard collective and a high-risk collective. The standard collective contained 89 patients, who in the course of their pregnancy remained without any pathological findings. Fifteen patients, who were assigned to the high-risk collective, either developed a pregnancy-induced hypertension during their pregnancy or an intrauterine fetal growth retardation. The Doppler-sonographic examination of the Aa. uterinae was applied for the first time between the 6 and 8 weeks gestation (WG), then in the 9 WG, 10 WG, 11 WG, between the 12 and 14 WG, as well as between the 20 and 24 WG.

RESULTS

Contrary to published data, there can be traced a completely transformed flow pattern in the Aa. uterinae already during the first trimester to an increasing extent. This correlates with a positive outcome of the pregnancy. There is a definite association between pathological Doppler sonography in the first third of the pregnancy and the development of a uteroplacental insufficiency as well as a pregnancy-associated hypertension (SIH) in the further course of the pregnancy.

CONCLUSION

Doppler sonography is an approved method in order to become early attentive of a reduced uterine blood flow. Applying Doppler sonographic treatment of the maternal vessels, uteroplacental insufficiency can be traced at an early stage. Pregnancies, which might develop a pregnancy-associated hypertension (SIH) or a placental insufficiency, can be detected during the early pregnancy to decrease the morbidity rate and the mortality of premature newborns. Further studies in larger collectives are necessary to obtain adequate solid datasets and to further evaluate the clinical meaning and the significance concerning pathological maternal Doppler parameters.

Maternal cardiac function in early pregnancies with high uterine artery resistance

OBJECTIVE

To compare the maternal cardiac function and serum concentration of cardiac troponin T (cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in first-trimester patients, according to uterine artery Doppler velocimetry (UADV).

METHODS

This cross-sectional study included singleton pregnancies with normal UADV (n=17) and abnormal UADV (n=19). Maternal echocardiography was performed and blood samples were taken at 11-14 weeks. Echocardiographic parameters included: (a) left ventricular (LV) long axis velocities; (b) atrial size; (c) LV filling pressure; (d) the ratio of peak mitral flow velocity in early diastole and early mitral annular diastolic velocity (E/Ea ratio); and (e) the E/flow propagation velocity ratio. The maternal serum concentrations of cTnT and NT-proBNP were determined by sensitive and specific immunoassays.

RESULTS

Patients with abnormal UADV had higher estimated left ventricular filling pressure (P=0.004), higher E/Ea ratio (P=0.03), higher E/flow propagation ratio (P=0.02), and lower LV long axis velocity (P=0.02) than those with normal UADV. There were no significant differences in the maternal serum concentration of cTnT or NT-proBNP.

CONCLUSIONS

Patients with abnormal UADV in the first trimester have higher left ventricular filling pressure and may have left ventricular systolic dysfunction.

First-trimester Doppler investigation of the uterine circulation

There is now strong evidence that fetal events can significantly impact postnatal health and disease development. Doppler velocimetry can identify some early pathologic changes in pregnancy. Many investigators have tried to delineate the normal and pathologic models of the uterine circulation in the first trimester, but much has yet to be defined. A discrete amount of confusion derives from the incomplete knowledge of the initial placental development, and particularly the development of the intervillous circulation. This article comprehensively reviews the literature on first-trimester Doppler in both normal and complicated pregnancies, and briefly discusses potential future areas of application.

Correlation between first-trimester uterine artery Doppler indices and maternal serum free β-human chorionic gonadotropin and pregnancy-associated plasma protein A

OBJECTIVE

To assess the correlation between first-trimester uterine artery Doppler measurements and maternal serum levels of free beta-hCG and pregnancy-associated plasma protein A (PAPP-A).

DESIGN

Observational study.

SETTING

Teaching hospital.

PATIENT(S)

Four hundred thirty-three women at 10-14 weeks of gestation.

INTERVENTION(S)

Doppler ultrasound of the uterine arteries. Fluorimetric immunoassays for free beta-hCG and PAPP-A.

MAIN OUTCOME MEASURE(S)

Uterine artery mean resistance index (RI), pulsatility index (PI), and number of early diastolic notches. Maternal serum levels of free beta-hCG and PAPP-A.

RESULT(S)

There were 401 uncomplicated pregnancies. In this group, free beta-hCG and PAPP-A did not significantly correlate with uterine artery RI or PI (r values between -0.089 and 0.029, all nonsignificant). Free beta-hCG and PAPP-A levels did not significantly change with the number of notches. Uterine artery resistance and PAPP-A levels were independently correlated with birth weight.

CONCLUSION(S)

Preliminary evidence suggests that first-trimester uterine artery Doppler measurements do not correlate with maternal serum levels of free beta-hCG and PAPP-A. This may allow their combined use in multivariate screening for pregnancy complications.

First trimester uterine artery Doppler abnormalities predict subsequent intrauterine growth restriction

OBJECTIVE

This study was undertaken to evaluate the association between uterine artery Doppler velocimetry performed between 10 and 14 weeks gestation and intrauterine growth restriction (IUGR).

STUDY DESIGN

Uterine artery Doppler velocimetry data were collected on 1067 women enrolled in the FASTER trial at the University of Colorado site. The data were analyzed by using univariate and multivariable logistic regression analysis.

RESULTS

The uterine artery mean resistance index (RI) for the entire cohort was equal on the right and left sides (0.59 +/- 0.14). Of the 1067 women, 34.2% had unilateral or bilateral diastolic notches, 1 notch was observed in 23.8%, and bilateral notches in 10.4%. Women with a high uterine artery mean RI (> or = 75th percentile) were 5.5 times more likely to have IUGR (95% CI 1.6-18.7). There was no significant relationship between notching and IUGR.

CONCLUSION

Elevated first trimester uterine artery mean RI is significantly associated with IUGR.

Prospective Evaluation of Uterine Artery Flow Velocity Waveforms at 12–14 and 22–24 Weeks of Gestation in Relation to Pregnancy Outcome and Birth Weight

OBJECTIVE

Uterine artery flow velocity was prospectively assessed using Doppler ultrasound at 12-14 and 22-24 weeks of gestation in the prediction of subsequent complications related to uteroplacental insufficiency: preeclampsia, pregnancy-induced hypertension, fetal growth restriction, fetal death and placental abruption, and to elucidate its relationship with birth weight.

METHODS

Uterine artery Doppler assessment was obtained during routine ultrasound screening in 263 unselected women. Flow velocity waveforms were coded according to the number of notches present at each scanning, respectively: none (0, 0), uni-/bilateral notches that disappeared (1, 0) or (2, 0), uni-/bilateral notches that persisted unilaterally (1, 1) or (2, 1), and persistent bilateral notches (2, 2).

RESULTS

Complete outcome data was obtained for 243 (92.4%) women. Of these women, 55 (22.6%) and 84 (34.6%) women had uni- and bilateral notches, respectively, at 12-14 weeks' gestation; 14 (5.8%) and 21 (8.6%) patients had uni- and bilateral notches, respectively, at 22-24 weeks' gestation. Analysis of complication rates for the four groups showed that they increased with notch persistence (5.7, 13.5, 57.1 and 76.2%), while the corresponding mean birth weight declined (3,273, 3,180, 2,698 and 2,418 g).

CONCLUSION

The absence or early disappearance of uterine artery notches is associated with fewer complications related to uteroplacental insufficiency and normal birth weight, whereas their late and partial disappearance or bilateral persistence tends to compromise the prognosis.