Pregnancy in women having chronic renal insufficiency and undergoing hemodialysis is a rare event with a poor outcome. This is the 1st case in whom pre- and posthemodialysis fetal renal artery Doppler flow velocimetry was used in conjunction with fetal blood sampling which was performed to assess fetal karyotype and ...

OBJECTIVES: To conduct a prospective evaluation of the incidence and neonatal outcome of fetuses with persistent right umbilical vein. This condition had traditionally been considered to be extremely rare and to be associated with a very poor neonatal prognosis, but later evidence has raised some doubts about the veracity of ...

Color pulsed Doppler ultrasound was used to examine the uterine arteries of a total of 265 normal pregnant women during 22-28 weeks' gestation at the Division of Maternal-Fetal Medicine, King Chulalongkorn Memorial Hospital. Reference ranges for pulsatility index (PI) were determined and throughout this gestational range, the mean values were ...

OBJECTIVE: The purpose of this study was to determine the sensitivity and specificity for acidosis of intrapartum fetal oxygen saturation measured by reflectance pulse oximetry. STUDY DESIGN: Intrapartum fetal oxygen saturation values per labor stage were correlated with umbilical artery pH, base excess and PCO(2) by regression analysis. Receiver operating ...

OBJECTIVE: The aim of the study was to evaluate the prognostic factors for survival of growth-restricted fetuses with absent end-diastolic velocity in the umbilical artery. STUDY DESIGN: Forty-five intrauterine growth-restricted fetuses with either absent end-diastolic (34 fetuses) or reverse flow (11 fetuses) in the umbilical artery were studied. The clinical ...

OBJECTIVE: To assess the inter- and intraobserver reproducibilities of pulsed Doppler measurements of the maternal renal circulation in normal pregnancies and those affected by pregnancy-induced hypertension. MATERIALS AND METHODS: Color and pulsed Doppler ultrasound was used to measure acceleration time and resistance index in the renal segmental and interlobar arteries. ...

Late pregnancy in rats is characterized by a decrease in arterial pressure and in isolated arterial vessels response to vasoconstrictors. In uterine arteries the pregnancy-associated attenuation of the response to vasoconstrictors has been attributed to an increase in basal and agonist-induced endothelial NO production. However, the role of NO in ...

Despite the essential role of the placenta in pregnancy, the control of the blood flow within the fetoplacental circulation is poorly understood. A handful of myography studies have directly assessed the role of vasoactive agonists in fetoplacental vasculature contractility but have used a range of steady-state conditions. Our aim, therefore, ...

OBJECTIVE: The purpose of this retrospective analysis was to compare pregnancy outcomes in growth-restricted fetuses retaining normal umbilical artery Doppler flow and the outcomes of pregnancies with end-diastolic velocity either diminished or severely reduced/absent. METHODS: One hundred pregnant women with growth-restricted fetuses were followed with Doppler velocimetry of the umbilical ...

OBJECTIVE: We examined the hypothesis that fetal proinflammatory cytokine release is a feature of placental vascular disease causing fetal compromise. We measured the concentrations of fetal proinflammatory cytokines interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and interleukin-8 (IL-8) in the presence of vascular disease in the umbilical placental villous ...

Intrauterine growth restriction (IUGR) is a common complication in pregnancy and influences morbidity and mortality at all stages of life. Historically, the management of IUGR has been dependent on antenatal biophysical testing and umbilical artery Doppler studies. With recent Doppler studies of the fetal central circulation, including intracardiac flows and ...

OBJECTIVE: To provide reference values for the umbilical coiling index in uncomplicated pregnancy. METHODS: Umbilical cords were collected from livebom singleton infants born after uncomplicated pregnancies. The umbilical coiling index (UCI) was calculated as the number of coils divided by the cord length in centimeters. The mean value (SD) for ...

OBJECTIVE: To compare uterine artery blood flow in normal first-trimester pregnancies with those complicated by uterine bleeding. METHODS: Uterine artery blood flow was investigated by transvaginal color Doppler in 46 pregnant women affected by uterine bleeding and in a control group of 35 women with normal intrauterine pregnancy. Gestational age ...

The objective of this study is an attempt to evaluate the best ultrasonic method of diagnosing intrauterine growth restriction (IUGR); a retrospective study of patients with singleton pregnancies who had been scanned at the author's institution within 2 weeks of their delivery was undertaken. Estimated fetal weight, abdominal circumference, head ...

Pregnancy is associated with a substantial increase in uterine artery blood flow, which may in part result from dilation in response to vascular endothelial growth factor (VEGF). Uterine blood flow is reported to be reduced in globally diet-restricted pregnant rats. Both global and protein dietary restriction in pregnancy produce programmed ...

Effects of distance lags between landfills and monitoring wells on contaminant detection capability were quantified in several groundwater velocity settings. Detection efficiency calculations were made with and without imposing a time limit on contaminant travel. In general, longer distance lags yielded higher detection efficiencies. However, detection efficiencies decreased as monitoring ...

OBJECTIVE: To assess the value of different admission tests in predicting the outcome of small-for-gestational age (SGA) fetuses with normal Doppler waveforms in the umbilical artery. METHODS: Criteria for admission into this retrospective study included: singleton pregnancy with a birth weight < 10th centile; absence of severe maternal complications; no ...

BACKGROUND: Pregnancy is associated with marked alteration in cardiovascular hemodynamics. Recent reports have characterized the effects on cardiac systolic function. Little has been written on the influences of loading conditions on Doppler measures of diastolic function during pregnancy. HYPOTHESIS: Stage of pregnancy has an impact on Doppler indices of diastolic ...

AIM: To evaluate the detection rate of fetal anemia and pregnancy outcome as related to our policy of monitoring pregnancies with red blood cell alloimmunization. METHODS: From August 1997 to July 2000 35 pregnant women with maternal red blood cell alloantibodies were monitored by ultrasonographic measurements of the fetal spleen ...

The umbilical cord is a critical connection between the embryo (and later, the fetus) and the placenta. The umbilical cord houses the blood vessels that are responsible for nourishing the fetus. Proper umbilical cord function is essential for growth and development before birth. A review of the embryologic origin of ...

BACKGROUND AND OBJECTIVE: The study was designed to evaluate whether the administration of sevoflurane in 100% oxygen for anaesthesia during Caesarean section would improve fetal and neonatal oxygenation compared with the administration of sevoflurane with 50% nitrous oxide in oxygen. METHODS: The randomized, single-blind controlled study examined 24 mothers, ASA ...

OBJECTIVE: The purposes of our study were to assess the ability of color and power Doppler sonography to depict the blood flow in the intraplacental villous arteries and to evaluate whether the blood flow of intraplacental villous arteries in a normal pregnancy is different from that in a pregnancy that ...

OBJECTIVE: To identify the temporal sequence of abnormal Doppler changes in the fetal circulation in a subset of early and severely growth-restricted fetuses. METHODS: This was a prospective observational study in a tertiary care/teaching hospital. Twenty-six women who were diagnosed with growth-restricted fetuses by local standards before 32 weeks' gestation ...

OBJECTIVE: To investigate the relationship between nuchal translucency thickness and cardiac flow velocity in normal fetuses at 11-13 weeks of gestation. Subjects and METHODS: Eighteen normal pregnancies were prospectively studied with transvaginal sonography and pulsed and color Doppler ultrasound. Flow velocities at the fetal atrioventricular valves (mitral and tricuspid valve) ...

OBJECTIVE: To assess the diagnostic value of Doppler sonography of the uterine arteries (DSUA) at 20-23 gestational weeks as screening procedure in a low risk population. PATIENTS AND METHODS: The study group consisted of 7508 singleton low-risk pregnancies. Doppler sonography of both uterine arteries was performed as routine part of ...

Three-dimensional power Doppler sonography is a unique instrument that enables assessment of vascular signals within the whole investigated area. Hemodynamical changes included in the process of early placentation are one of the most exciting topics in investigation of early human development. This investigation was designed as an observational cross-sectional study. ...

The aim of this study was to evaluate the uteroplacental vascular characteristics during the first trimester of normal and failed pregnancies. A clinical descriptive study was conducted using colour Doppler ultrasound in 45 women with normal pregnancies (group A) and 44 with non-embryonic sac or missed abortions (group B). The ...

THE AIM: To record blood flow velocimetry in the fetal superior mesenteric artery in normal pregnancy and to evaluate if blood flow recordings in the vessel might predict adverse outcome in high-risk pregnancy. METHODS: The fetal superior mesenteric artery blood velocimetry was recorded in a cross sectional manner in 75 ...

OBJECTIVE: This study was performed in order to compare the performance of classical two dimensional (2D) and three dimensional (3D) ultrasound, both with power Doppler technology, in the visualization of the placental vascular network during ongoing pregnancy. METHODS: 15 pregnant volunteers in the third trimester of pregnancy were examined by ...

OBJECTIVES: The purpose of the present study was to test the hypothesis that pregnancy is associated with an attenuation of the vasoconstrictor response not only in the uterine, but also in the systemic circulation. Decreased vascular reactivity should be characterized by an early onset to account for the rapid fall ...

OBJECTIVE: To examine the value of uterine artery Doppler at 11-14 weeks of gestation in the identification of women at risk of developing pre-eclampsia and fetal growth restriction. METHODS: Uterine artery Doppler was carried out at 11-14 weeks in 3324 consecutive singleton pregnancies attending for routine care in three London ...

OBJECTIVE: To determine uterine artery impedance using Doppler in the second and third trimesters at sea level and at high altitude. METHODS: Uterine artery resistance and pulsatility indices (RI and PI, respectively) were obtained by Doppler velocimetry from 242 women in Cerro de Pasco (4300 m altitude) and 200 women ...

OBJECTIVE: To describe the time sequence of changes in fetal monitoring variables in intrauterine growth restriction and to correlate these findings with fetal outcome at delivery. METHODS: This was a prospective longitudinal observational multicenter study on 110 singleton pregnancies with growth-restricted fetuses after 24 weeks of gestation. Short-term variation of ...

OBJECTIVE: To evaluate placental volume and uterine artery Doppler in the first trimester in the prediction of pregnancies that subsequently develop pre-eclampsia, pregnancy-induced hypertension, preterm placental abruption or fetal growth restriction. METHODS: In 380 singleton pregnancies attending our center for nuchal translucency screening at 11-14 weeks of gestation, Doppler assessment ...

OBJECTIVE: To establish whether asymptomatic normotensive pregnant women with an abnormal uterine Doppler velocimetry, have haematological changes characteristic of congenital or acquired thrombophilia, and whether this information improve predict in pregnancy complications. STUDY DESIGN: A prospective study involved the enrolment of 30 healthy normotensive pregnant women between the 23rd and ...

OBJECTIVE: To evaluate changes in left ventricular mass and diastolic function during normal pregnancy. METHODS: This was a cross-sectional study of 125 pregnant women at 9-42 weeks of gestation and 19 non-pregnant female controls. Two-dimensional and M-mode echocardiography of the maternal left ventricle and left atrium was performed. RESULTS: During ...

OBJECTIVE: To examine the effect of antenatal steroids on the biophysical profile and the Doppler parameters of umbilical and middle cerebral arteries of healthy fetuses. STUDY DESIGN: Thiry-five singleton pregnancies between the gestational ages of 28 and 34 weeks, who received two consecutive doses of betamethasone 24h apart to accelerate ...

Active perifollicular angiogenesis in ovaries and endometrium is linked with the quality of oocytes and endometrial receptivity, and consequently with the outcome of implantation. Studies evaluating ovarian velocimetry in relation to implantation and pregnancy rates bring essentially into play velocity values or non-quantitative parameters, whose reproducibility is low and which ...

BACKGROUND: Pulsation in the flow velocity waveform in the umbilical vein is related to perinatal mortality but the flow velocity waveform in the fetal vein of Galen is normally even and without fluctuation. OBJECTIVES: To establish whether blood flow velocity pulsations in the vein of Galen in high-risk pregnancies are ...

OBJECTIVE: To study second-trimester maternal cardiac adaptation in asymptomatic patients at risk, on the basis of abnormal uterine artery Doppler, for the development of gestational hypertension or having a small-for-gestational age fetus. Fetal and maternal outcomes were verified at the end of pregnancy. METHODS: Thirty-six normotensive women with abnormal uterine ...

In the first weeks of pregnancy, columns of endovascular cytotrophoblastic plugs develop in the lumen of spiral arteries. Morphologic data show that these plugs become loosened as soon as the end of the second month and the intervillous circulation of maternal blood is likely to be established progressively between the ...

BACKGROUND: We attempted to establish normal Doppler flow velocity waveform patterns in the human fetal ductus venosus (DV), and also to establish a standardized measurement technique. METHODS: Ductus venosus blood flow was measured in a prospective study involving 545 fetuses aged between 8 and 38 weeks in utero, the mothers ...

The fetal umbilical and cerebral Doppler changes were recorded in a 27-year-old primigravida referred at 38 weeks for the treatment of an iliofemoral vein thrombosis. On admission and in comparison to a previous Doppler assessment systematically performed during growth scan at 37 weeks, the umbilical resistance index (URI) demonstrated an ...

Pregnancy produces marked systemic vasodilation, but the mechanism is unknown. Experiments were performed in conscious rabbits to test the hypotheses that increased nitric oxide (NO) production contributes to the increased vascular conductance, but that the contribution varies among vascular beds. Rabbits were instrumented with aortic and vena caval catheters and ...

OBJECTIVE: The purpose of this study was to determine the effects of pregnancy and of maximal exercise on left ventricular diastolic filling response. STUDY DESIGN: Transmitral pulsed Doppler echocardiography was obtained in 10 healthy women during each trimester of pregnancy and at 12 weeks after delivery. Doppler studies were performed ...

BACKGROUND: Blood flow is calculated from mean velocity across the vessel and its cross-sectional area and is related to the fetal growth. AIM: To investigate the relationship between diameter pulse waveform (DPW) and flow velocity waveform (FVW) in the fetal descending aorta during fetal development. STUDY DESIGN: Doppler ultrasound and ...

PROBLEM: Pregnancies in women with antiphospholipid syndrome (APS) are associated with obstetric complications despite treatment. The present study analyzes risk factors and evaluates fetal outcome in a large sample of treated APS pregnancies. METHOD OF STUDY: Seventy-seven pregnancies in 56 women were included. Twelve selected variables potentially related to the ...

OBJECTIVE: To determine the influence of vaginal bleeding with or without a persisting subchorionic hematoma on uteroplacental, umbilicoplacental and yolk-sac hemodynamics in early pregnancy. DESIGN: Twenty-six consecutive patients with vaginal bleeding entered this longitudinal study 1-3 days after the beginning of vaginal bleeding and were re-examined every 1-2 weeks. In ...

Adrenomedullin (AM) is a potent vasodilator. Pregnancy-induced hypertension (PIH) is a common cause of maternal or fetal mortality. We measured the changes of adrenomedullin receptor components gene expression, receptor activity-modifying protein 2 (RAMP2) and calcitonin receptor-like receptor (CRLR), at feto-maternal tissues in human normotensive pregnant women and pregnancy-induced hypertensive women ...

OBJECTIVE: To determine obstetrical risk factors and pregnancy outcome of fetuses with true knot of the umbilical cord. METHODS: Study population included 69,139 singleton deliveries occurring between the years 1990-1997. Data were retrieved from the database of the Soroka University Medical Center. Fetuses with malformations were excluded. RESULTS: The incidence ...