BACKGROUND Despite the known effects of neuraxial blockade on major vessel function and the rapid decrease in uterine vascular impedance, it is unclear how the blockade affects the utero-placental circulation in the near-term. We hypothesize that among women with chronic hypertension, a loss of sympathetic tonus consequent to spinal block may cause significant changes in the utero-placental hae...

Aim—To determine whether antenatal administration of thyrotrophin releasing hormone (TRH), to promote lungmaturation, alters blood flow through the fetal middle cerebral, umbilical artery, or ductus arteriosus and through the maternal uterine arteries. Methods—The eVect of transplacentally administered TRH on the fetal circulation was prospectively evaluated in 30 patients between 24 and 34 wee...

Right and left ventricular outputs were measured by a dye dilution technique in fetal lambs before and during graded reduction of umbilical blood flow by constriction of the abdominal portion of the umbilical vein. POo, PCO2 and pH were measured on blood samples taken from the carotid artery and the ductus arteriosus. Oxygen saturation values were estimated from oxygen dissociation curves for f...

Aim: To evaluate fetal thymus size using the thymic-thoracic ratio (TTR) in women with a pregnancy complicated growth restriction (FGR) and to assess relationship adverse perinatal outcomes. 
 Materials Method: A total of 35 pregnant FGR 42 healthy similar demographic characteristics were included this prospective study. In group, cases pathological doppler flow parameters absent end-diast...

Regulation of endothelial cell (EC) plasminogen activator inhibitor type-1 (PAI-1), the primary physiological inhibitor of tissue-type plasminogen activator (TPA) and urokinase-type plasminogen activator (UPA), by various stimuli has been well characterized. We report the upregulation of secreted and intracellular PAI-1 in human umbilical ECs when cocultured with human smooth muscle cells (SMCs...

Bradykinin (BK) and serotonin (5-HT) are vasoactive agents that significantly contribute to the normal functioning of fetoplacental blood flow, including modulation of smooth muscle tone in umbilical vein and arteries. Accordingly, umbilical artery is a crucial component of fetoplacental circulation with the vital function of providing suitable perfusion and nutrition for placenta. The aim of t...

Fetuses with deviations in the normal left versus right weight relationships of the paired viscera were examined for correlation with particular malformations, syndromes, or other common factors. Alterations of the normal pattern were observed among cases with cytogenetic anomalies, diaphragmatic hernia, renal duplication, dyshydramnios, and single umbilical artery. A reversal of the left versu...

In a total of 42 consecutive pregnancies with intrauterine growth retardation (IUGR), Doppler velocimetry was related to neonatal outcome as determined by Apgar score at 1 min, umbilical artery acid-base status and PO2, number of nucleated red blood cells (NRBC), duration of ventilatory support, and sonographic appearance of cerebral leukomalacia. Doppler flow velocity waveforms were obtained f...

34 35 The present study was conducted to determine the impact of suppressing trophoblast 36 remodeling of the uterine spiral arteries by prematurely elevating estrogen levels in the first 37 trimester of baboon pregnancy on uterine and umbilical blood flow dynamics. Uteroplacental 38 blood flow was assessed by Doppler ultrasonography after acute administration of saline (basal 39 state) and ser...

Pregnant ewes and their fetuses were instrumented between 110 to 120 days of gestation (term, 145 days) for monitoring heart rate, blood pressure, uterine artery blood flow, and fetal intra-abdominal umbilical artery blood flow and arterial blood gases. DOM (2,5-dimethoxy-4methyl-amphetamine) was administered intravenously to the ewe in doses of 1, 2.5, 5, 10, or 20 fig/kg. Maternal administrat...