Impaired trophoblastic invasion of the maternal spiral arteries is associated with increased risk for subsequent development of intrauterine growth restriction, preeclampsia, and placental abruption. A series of screening studies involving assessment of impedance to flow in the uterine arteries have examined the potential value of Doppler in identifying pregnancies at risk of the complications of impaired placentation. Currently we are able to characterize uteroplacental perfusion with quantitative and qualitative methodologies. This review will examine both methodologies and seek to highlight conclusive and inconclusive findings.
"Doppler ultrasound enables the assessment of blood flow parameters for the adequate and reduced perfusion in vivo. Impaired trophoblastic invasion of the maternal spiral arteries is shown to be associated with increased impedance to flow in the waveforms obtained by Doppler ultrasound examination of the UtA  . Bilateral high-resistance flow velocity waveforms with early diastolic notches at 22nd–26th gw are associated with subsequent fetal death, intrauterine growth restriction (IUGR) and preeclampsia . "
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to examine plasma levels of fibronectin and plasminogen inhibitor type 1 (PAI-1), and alterations in uterine artery (UtA) waveforms throughout normotensive and preeclamptic pregnancies and to analyze its predictive value for the detection of preeclampsia within the second trimester of pregnancy.
Blood samples were collected from 102 healthy, nulliparous women between the 24th and 26th gestational week. Preeclampsia developed in 13 patients; 89 normotensive control subjects were matched from the same cohort. Plasma samples were assayed for fibronectin and PAI-1 by enzyme-linked immunosorbent assay. Color pulsed Doppler examinations of UtA were performed after blood sampling. Trends were compared between two groups.
Maternal plasma fibronectin and PAI-1 levels and average PI, RI and S/D ratios of patients with preeclampsia were significantly higher (p< 0.05). The best cut-off values for predicting preeclampsia of fibronectin, PAI-1, PI, RI, S/D ratio based on ROC curve analysis were 290 mg/ml, 77.3 ng/ml, 1,0615, 0.605 and 2,59 respectively. The areas under the curve equal to 0.705, 0.753, 0.689, 0.695 and 0.699 for fibronectin, PAI-1 and uterine artery Doppler PI, RI, S/D ratio were determined for the prediction of preeclampsia.
Fibronectin, PAI-1 and UtA Doppler are potentially useful predictors of preeclampsia. Maternal plasma PAI-1 combinated with fibronectin had the highest predictive values in our study.
[Show abstract][Hide abstract] ABSTRACT: The assessment of the hemodynamics in the maternal and fetal blood circulation currently relies on the color doppler and spectral doppler US techniques. Although several studies have proven the reliability of such methods, the complex morphology of the investigated vessels still causes several limitations. An alternative, high resolution technique, named MSDA, has been recently introduced for the investigation of fetal-maternal circulation. This work reports several examples selected among the data collected on more than 150 healthy and pathological pregnancies over 1 year of multi-centre screening. The presented results suggest that MSDA represents a method suitable to improve the accuracy in predicting pregnancy complications and in detecting pathological events. Prospective studies are needed to determine the utility of this technique in predicting placenta mediated complications.
Proceedings of the IEEE Ultrasonics Symposium 01/2007; DOI:10.1109/ULTSYM.2007.617
[Show abstract][Hide abstract] ABSTRACT: Oligohydramnios is related to adverse perinatal outcomes particularly when associated with fetal growth restriction. The purpose of this study was to delineate predictors of adverse perinatal outcomes in cases of preterm idiopathic oligohydramnios associated with appropriate-for-gestational-age (AGA) fetal biometry. A database of preterm AGA fetuses (< 37 weeks) presenting for evaluation of idiopathic oligohydramnios (defined as an amniotic fluid index [AFI] < 10th percentile) in the third trimester with delivery information and uterine artery Doppler indices (average resistance index [RI] and bilateral notching) available was prospectively collected ( N = 90). AFI and birth weight (BW) percentiles were calculated using standard tables. Chi-square and Student T test were used to evaluate for predictors of adverse perinatal outcomes including BW < or = 10th percentile, stillbirth, neonatal intensive care unit admission, 5-minute Apgar score < 7, preterm delivery < 35 weeks, and preeclampsia. Patients destined to experience poor perinatal outcomes (22%) were demographically similar to those experiencing normal outcomes in terms of maternal age ( P = 0.5), ethnicity ( P = 0.9), body mass index ( P = 0.3), and parity ( P = 0.9). However, at-risk patients were more likely to present with oligohydramnios at an earlier gestational age (GA) than those not at risk (33.0 +/- 3.0 versus 34.4 +/- 2.0 weeks; P = 0.02). There were no differences in perinatal outcomes associated with AFI percentile ( P = 0.9), increased average uterine artery RI ( P = 0.5), bilateral notching ( P = 0.4) or a combination of increased uterine artery RI and bilateral notching ( P = 0.2). Patients with preterm AGA fetuses who present with idiopathic oligohydramnios at an earlier GA are at risk for adverse perinatal outcomes compared with those presenting later in gestation. Sonographic indices, particularly uterine artery Doppler findings, were not found to be useful predictors of adverse outcomes.
American Journal of Perinatology 10/2008; 26(1):21-5. DOI:10.1055/s-0028-1091392 · 1.91 Impact Factor
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