OBJECTIVE: To characterize umbilical-placental blood flow gradient during early second trimester of pregnancy. METHODS: Forty normal pregnant women with a singleton fetus gave their informed consent to participate in this study. All scans were preformed between 12 and 20 weeks' gestation using the simultaneous multigate spectral Doppler imaging (MS-SDI) modality ...

OBJECTIVE: This study was undertaken to test for structural differences between myometrial radial arteries isolated from women having normal pregnancies and pregnancies complicated by preeclampsia and intrauterine growth restriction. STUDY DESIGN: Pressure myography was used to study myometrial radial arteries obtained at cesarean section. With the use of a transilluminating ...

Our aim was to review the literature on umbilical cord coiling. Relevant articles in English published between 1966 and 2003 were retrieved by a Medline search and cross-referencing. The normal umbilical cord coiling index (UCI) is 0.17 (+/- 0.009) spirals completed per cm. Abnormal cord coiling, i.e. UCI <10th centile ...

The progressive rise in uterine blood flow during pregnancy is accompanied by outward hypertrophic remodeling of the uterine artery (UA). This process involves changes of the arterial smooth muscle cells and extracellular matrix. Acute increases in blood flow stimulate endothelial production of nitric oxide (NO). It remains to be established ...

OBJECTIVE: To evaluate the relationship between umbilical artery pulsatility index and the umbilical cord pH in small-for-gestational-age fetuses. METHODS: Data were collected from all pregnancies seen in our Fetal Surveillance Unit that underwent antenatal monitoring for being small-for-gestational-age beyond 24 weeks of pregnancy. A linear regression was used to analyse ...

To study the efficacy of yoga on the outcome of complicated pregnancy, 121 women attending antenatal clinic at Gunasheela Surgical and Maternity Hospital (GSMH) in Bangalore, India, were enrolled between 18-20 weeks of pregnancy in a prospective, matched, observational study. Sixty-eight women were in the yoga group and 53 women ...

OBJECTIVE: To investigate whether an atypical umbilical coiling pattern at prenatal sonography is associated with adverse pregnancy outcome. METHODS: A targeted sonographic evaluation of the umbilical cord (UC) was performed in 758 women with singleton gestation, and gestational age above 20 weeks. Atypical coiling was defined as the presence of ...

PURPOSE: This study was conducted to determine possible maternal age-related changes in uterine artery impedance in normal late pregnancy. PATIENTS AND METHODS: In a cross-sectional design study, Doppler velocimetry of the uterine vessels was performed in 884 pregnant women with normal, late, singleton pregnancies. We hypothesized that maternal age is ...

During a four-year period we analyzed the significance, sensitivity and sensibility of myoma Doppler flow during pregnancy in relation to the course and outcome of the pregnancy and to later histopathological findings. By following 36 older primigravidas with determined myomas, we observed the course of the pregnancies in all trimesters ...

OBJECTIVE: To determine the value of uterine artery velocimetry and mid-trimester maternal serum AFP/hCG measurements in predicting pregnancy complications in a high-risk group of pregnant patients. METHODS: Eighty-eight patients with chronic hypertension, previous preeclampsia, and thrombophilia were included. Maternal serum AFP/hCG was examined between 15-16 weeks gestation. Levels > 3 ...

OBJECTIVES: To elucidate the hemodynamics of the uterine artery in normal and abnormal pregnancies by use of Doppler ultrasound and SQUID biomagnetometry. METHOD: Two hundred and three women (gestational age 28-42 weeks) were included in the study. Forty-three of them had preeclampsia and/or intrauterine growth restriction and 160 were normal. ...

OBJECTIVE: Our objective was to test the hypothesis that systemic blood pressure (BP) is increased above normal in intrauterine growth restricted (IUGR) fetal lambs with elevated umbilical artery (UmA) Doppler indices. STUDY DESIGN: Five pregnant ewes were exposed to hyperthermic conditions for 80 days beginning at 40 days' gestation (dGA) ...

OBJECTIVE: The purpose of this study was to determine whether, when, and how rates of short-term neonatal complications increase beyond 37 weeks of gestation. STUDY DESIGN: A retrospective cohort study was conducted of all low-risk, term, cephalic, and singleton births that were delivered at the University of California, San Francisco, ...

The aim was to determine experimentally the factors that increase the risk of venous occlusion by applying a standardised tightening force to isolated perfused umbilical cords tied in a true knot in vitro. Umbilical cords were collected from patients undergoing Caesarean section. Cords were clamped, isolated and studied within 15 ...

OBJECTIVE: To evaluate the effect of nifedipine on placental and fetal middle cerebral and atrioventricular Doppler waveforms. METHODS: Doppler waveforms of uterine (UtA), umbilical (UA) and middle cerebral (MCA) arteries and both atrioventricular valves were measured from 21 pregnant women/fetuses prior to and during nifedipine therapy for preterm labor. Maternal ...

OBJECTIVE: To determine to what extent adverse pregnancy outcomes are associated with thrombophilia. STUDY DESIGN: We studied 31 women who had HELLP syndrome, placental abruption, fetal growth restriction or unexplained stillbirth (study group), matched with 12 controls. All women were tested for: Factor V, Prothrombin, methylenetetrahydrofolate reductase gene (MTHFR) mutations; ...

OBJECTIVE: To construct normal ranges for umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI) and cerebroplacental ratio (CPR) in prolonged pregnancies according to strict methodological criteria using polynomial regression analysis. METHODS: This was a retrospective, cross-sectional observational study involving 140 women, 10 women for each ...

BACKGROUND: Umbilical vein constriction at the fetal abdominal inlet is a common finding after week 13, when the period of umbilical herniation is brought to an end. AIMS: To test the hypothesis that a constricting umbilical ring within physiological ranges affects fetal hemodynamics by either pooling blood in the placenta ...

The current evidence on the primary source of ammonia production in the human fetoplacental unit is potentially misleading. The aim of the present investigation was to determine the concentration of ammonia in human maternal and fetal blood at birth and to compare them with published data in late gestation sheep. ...

OBJECTIVE: To investigate the correlation between Doppler parameters in the umbilical and fetal middle cerebral arteries and pregnancy outcome in women with gestational diabetes mellitus (GDM). METHODS: A prospective study was performed on 169 singleton GDM pregnancies in a university teaching hospital from January to December 2002. Umbilical artery (UA) ...

Our objective was to evaluate the utility of gray-scale placental ultrasound for the detection of pathological lesions in the placentas of preterm pregnancies with abnormal fetoplacental blood flow (defined by absent or reversed end-diastolic flow velocities [ARED] in the umbilical arteries) before 32 weeks of gestation. Sixty consecutive structurally and ...

The objective of this study was to evaluate the role of uterine, endometrial and follicular blood flow in prediction of ongoing pregnancy after assisted conception. A prospective observational study was conducted on 53 women undergoing IVF treatment. Transvaginal colour and pulsed Doppler measurements were performed on the day that pituitary ...

OBJECTIVE: To evaluate and compare umbilical cord thickness of aneuploid fetuses with umbilical cord diameter nomograms generated from euploid fetuses between 14 and 23 weeks' gestational age. METHODS: A retrospective study was conducted in which 56 fetuses and neonates had diagnoses of abnormal karyotypes, of which 46 fetuses had numerical ...

OBJECTIVE: Pregnancies with myomas are known to have an increased risk for complications such as abruptio placentae, dysfunctional labor, growth of the tumor, necrosis and delivery problems, but prediction is still difficult based on clinical and real-time ultrasound evaluations alone. METHODS: We evaluated 15 patients with submucosal, intramural and subserous ...

The relationship of large and vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We present a patient with a large placental tumor and signs of impending fetal cardiac failure. The angioarchitecture of the tumor depicted by three-dimensional (3D) power Doppler ultrasound enabled us to accurately diagnose a placental chorioangioma. ...

S-nitrosohemoglobin (HbSNO), where hemoglobin (Hb) is nitrosated at Cysbeta93, presumably controls delivery of the vasorelaxant nitric oxide (NO) to hypoxic tissues in an oxygen-sensitive manner. Little is known about how Hb regulates NO bioavailability during fetal development. A study was planned to determine the levels of HbSNO and HbFe(II)NO (NO ...

OBJECTIVE: To estimate the pattern of maternal vascular reactivity in normal and high-risk pregnancies using postocclusion brachial artery diameter. METHODS: Prospective, longitudinal study of 44 low-risk singleton pregnancies and 28 high-risk pregnancies, defined as pregestational diabetes (n = 7), chronic hypertension (n = 4), twin gestation (n = 6), and ...

OBJECTIVE: In previous pilot studies, fetal vein of Galen (GV) blood velocity has been shown to be non-pulsatile in normal pregnancies. A pulsating pattern in high-risk pregnancies has been related to adverse outcome of pregnancy. The aim of this study was to establish reference ranges for fetal cerebral venous blood ...

OBJECTIVE: Elevated counts of nucleated red blood cells (NRBCs), as well as prolongation of pregnancy, have been suggested as predictors of adverse perinatal outcome. However, the association between these 2 variables has received only minimal attention. We sought to evaluate fetal NRBCs in prolonged pregnancies. METHODS: Umbilical cord blood was ...

OBJECTIVES: The purpose of this study was to determine if maternal undernutrition during pregnancy altered myogenic tone in small radial uterine arteries. STUDY DESIGN: Myogenic tone of radial uterine arteries was studied from late pregnant rats (day 20) that were fed either ad libitum or globally restricted diet (moderately severe ...

OBJECTIVE: The measurement and evaluation of ductus venosus (DV) blood flow velocity waveform in high-risk pregnancies has been studied intensively in recent years in order to find a more intermediate signal of fetal compromise. Our objective was to study the fetal outcome of pregnancies with intrauterine growth retardation (IUGR) and ...

OBJECTIVE: The progressive increase in uterine blood flow (UBF) during pregnancy is accommodated by morphologic changes in the uterine artery (UA) in a process defined as arterial remodeling. This process is accompanied by changes in cytoskeletal architecture of the arterial smooth muscle cells (SMCs) and surrounding extracellular matrix (ECM). Aging ...

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 ...

OBJECTIVE: To evaluate the efficacy of a uniform management protocol in antiphospholipid-antibody-positive obstetric patients with at least one second- or third-trimester intra-uterine fetal death. STUDY DESIGN: A prospective study of 33 successive pregnancies in antiphospholipid-antibody-positive patients, diagnosed after an intra-uterine fetal death. The management included treatment by a combination of ...

AIM: The aim of this prospective study was to assess the role of uterine artery colour Doppler waveform analysis in the prediction of adverse pregnancy outcome such as preeclampsia, intrauterine growth retardation, placental abruption or a combination of outcome parameters. METHODS: Various uterine artery Doppler ultrasound parameters (RI>0.58, RI>0.7 and ...

AIM: The aim of this prospective study was to assess the role of uterine artery color Doppler waveform analysis in the prediction of adverse pregnancy outcome such as preeclampsia, intrauterine growth retardation, placental abruption or a combination of outcome parameters in risk pregnancies (n=52). METHODS: Various uterine artery Doppler ultrasound ...

OBJECTIVE: The purpose of this study was to determine the clinical outcome of isoimmunized pregnancies managed primarily by middle cerebral artery peak systolic velocity. STUDY DESIGN: A retrospective chart review was conducted of isoimmunized pregnancies that underwent ultrasound examinations from January 1, 2001, through May 1, 2003. Ultrasound reports, laboratory ...

The complications of placental insufficiency, pre-eclampsia and fetal growth restriction (FGR) are major causes of perinatal as well as maternal morbidity and mortality. In normal pregnancy, impedance to flow in the uterine arteries decreases with gestation, and histopathological studies suggest that this is due to trophoblastic invasion of the spiral ...

OBJECTIVE: To evaluate the validity of systolic/diastolic (S/D) ratio of the umbilical artery in predicting intrauterine growth restriction (IUGR). STUDY DESIGN: Diagnostic test study. SETTING: Maharaj Nakorn Chiang Mai Hospital, Chiang Mai University. SUBJECTS: Two hundred and twelve singleton pregnancies between 30 and 42 weeks' gestation with clinical suspicion of ...

BACKGROUND: The role of antenatal risk factors associated with the occurrence of fetal growth restriction complicated by abnormal umbilical artery Doppler studies has not yet been studied extensively. We evaluated the role and the interactions of antenatal antecedents of fetal growth restriction complicated by abnormal umbilical artery end-diastolic velocities. METHODS: ...

OBJECTIVE: We report the case of a 36-yr-old woman with nesidioblastosis treated throughout pregnancy with high doses of octreotide. We studied the course of blood glucose, foetal growth and development. METHODS: Blood samples were obtained every month throughout pregnancy and taken at birth from the umbilical cord. Sonography was performed ...

OBJECTIVE: To evaluate the incidence and clinical relevance of intermittent absent and/or reversed diastolic flow on umbilical artery Doppler in different groups of monochorionic twin pregnancies. METHODS: This was a prospective study involving three groups of monochorionic pregnancies: Group 1: controls followed fortnightly from the first trimester (n = 80); ...

OBJECTIVE: In red blood cell (RBC) isoimmunized pregnancies fetal anemia is associated with a hyperdynamic circulation. The aim of the present study was to examine further the possible value of fetal middle cerebral artery peak systolic velocity (MCA-PSV) in the management of affected pregnancies. METHODS: A reference range of fetal ...

We assessed the accuracy of voiding color Doppler ultrasonography (US) with echo enhancement for diagnosis or exclusion of vesicoureteral reflux (VUR) versus voiding cystourethrography (VCUG) and evaluated patient tolerance of the echo-enhancing agent. One hundred twenty-two patients (ages range, 1 month to 17 years) with 244 ureterorenal units underwent voiding ...

OBJECTIVE: Heavy bleeding in the late postpartum has, in some cases, been attributed to subinvolution of the placental bed and enhanced myometrial vascularity (EMV) as seen on color Doppler imaging. The aim of this study was to investigate the incidence and spontaneous evolution of areas of enhanced vascularization over the ...

PURPOSE OF REVIEW: The purpose of this review is to summarize recently published studies on noninvasive diagnosis of fetal anemia in order to give recommendations for the use of these new tools. RECENT FINDINGS: Red cell alloimmunization remains one of the most common causes of fetal anemia. Amniocentesis and cordocentesis ...

The 'classical' concept that pregnancy-induced hypertension (PIH) and pre-eclampsia (PE) primarily originate from defective placentation in early pregnancy has been challenged recently. There is growing evidence that other factors, including maternal predisposing conditions, also play a significant role in the pathophysiology of PIH and PE. The aim of the present ...

OBJECTIVE: To explore the sonographic vascular architecture and the hyaluronan amount and distribution of umbilical cords of healthy and trisomy 21 fetuses in early gestation. MATERIAL AND METHODS: Umbilical cord sonographic morphology and morphometry of 112 consecutive normal fetuses and 11 trisomy 21 fetuses were assessed between 10 and 15 ...

Dilatation of the fetal intra-abdominal umbilical vein is a rare entity. It is unclear whether prenatally diagnosed umbilical vein dilatation is associated with an increased risk of fetal anomalies or poor perinatal outcome. Umbilical artery waveform notching may be a predictor of cord abnormalities. It seems reasonable following the baby ...

To test whether membrane-bound angiotensin I-converting enzyme (t-ACE) is involved in arterial remodeling, we applied unilateral carotid artery (CA) ligation and studied uterine arteries (UA) before, during, and after pregnancy in t-ACE-/- and t-ACE+/+ mice. RESULTS- In CA of t-ACE-/- mice, blood pressure, outer diameter (D), and medial cross-sectional area ...