Uterine and ovarian flow velocity waveforms in the normal menstrual cycle: a transvaginal Doppler study

A combined transvaginal 2D real-time and pulsed Doppler method was used for recording flow velocity waveforms in the uterine and ovarian arteries from 16 healthy women during the follicular and luteal phase of the normal menstrual cycle. Continuous forward end-diastolic flow velocities were documented in 74% of the ovarian artery and 96.5% of the uterine artery flow velocity waveforms. Comparison of the pulsatility index from the left and right ovarian artery revealed a significantly lower pulsatility index on the side of the ovary bearing the developing corpus luteum, suggesting reduced down-stream impedance or increased blood flow. The pulsatility index from the uterine artery only seems to be marginally involved in the observed impedance changes during the luteal phase of the menstrual cycle.     

Severe intrauterine growth retardation; assessment of its origin from fetal arterial flow velocity waveforms

Doppler blood flow velocity waveforms in the umbilical artery and fetal internal carotid artery were recorded in a total of 10 patients with severe intrauterine growth retardation (IUGR) and marked oligohydramnios to establish a fetal or utero-placental origin of IUGR. Gestational age varied between 28 and 37 wk. Negative maternal serology ruled out fetal infections. In six patients, IUGR was associated with abnormal flow velocity waveforms, indicating utero-placental insufficiency. Following delivery, these infants showed no structural defects; moderate to marked placental infarction was documented in 4 out of 6 cases. In the remaining four patients, IUGR was associated with normal flow velocity waveforms, suggesting a fetal origin of the IUGR. Following delivery, all four infants revealed structural defects, only one of which was diagnosed prenatally. Twice an abnormal karyotype was the underlying cause. There was no placental infarction. These preliminary data suggest that combined recording of the flow velocity waveform in the above-mentioned vessels may provide valuable additional information as to the cause of IUGR and as such be helpful in determining obstetric management.     

Umbilical artery Doppler velocimetry as a labor admission test

Doppler ultrasound of the umbilical artery flow velocity waveform was studied prospectively as an admission test at the labor ward. Recordings were made in 575 women in various stages of labor before, during, and after uterine contractions, and evaluated in relation to intrapartum and fetal outcome variables. No association was found between abnormal flow velocity waveforms and cord complications, meconium-stained amniotic fluid, or abnormal fetal heart rate tracing, nor was there any association with operative delivery for fetal distress or low Apgar scores at 1 and 5 minutes. Small for gestational age fetuses had significantly more abnormal flow velocity waveforms than appropriate for gestational age fetuses, and so had those with umbilical artery acidemia compared with those with normal pH. The results indicate that Doppler recording of the umbilical artery flow velocity waveform as an admission test at the labor ward is not a good predictor of fetal distress in an unselected population.     

Doppler blood flow changes and placental morphology in pregnancies with third trimester hemorrhage.

Combined real-time ultrasound and pulsed Doppler ultrasound examinations were performed in 67 patients with third trimester hemorrhage and other symptoms related to placental abruption, starting from the onset of symptoms to delivery. In 52 of the cases, placental morphology was investigated by light microscopy. Thirteen patients were ultimately given the diagnosis abruptio placentae. None of the morphological placental changes considered had any statistical relationship to placental abruption. Patients with placental centrocotyledon hemorrhages and infarction more often had abnormal umbilical artery flow velocity waveforms at the onset of symptoms, and more frequent abnormal arcuate artery flow velocity waveforms were found among those with placental infarction alone. Abnormal flow velocity waveforms in the umbilical and arcuate arteries were associated with placental abruption, both at the onset of symptoms and at the final examination before delivery. The results indicate an increased risk for placental abruption if the arcuate and/or umbilical artery flow velocity waveforms are abnormal in patients with third trimester hemorrhage.     

Second Trimester Colour Doppler Imaging of the Uterine Artery: Reproducibility of the Resistance Index

Summary: Second trimester assessment of uterine blood flow has been advocated as a predictor of subsequent adverse perinatal outcome. The reproducibility of uterine artery resistance index, as assessed using colour Doppler imaging, was investigated. Two observers, both of whom were experienced in colour Doppler assessment of uterine artery flow velocity waveforms, performed the measurements. One-way analysis of variance was used to evaluate intraobserver variability and the limits of agreement method was used to determine the 95% prediction interval for interobserver differences. The intraobserver standard deviation was small for both observers. The limits of agreement for interobserver differences were wide (- 0.24, 0.16), similar in magnitude to those reported by other workers who assessed the uterine vessel using continuous wave Doppler. The poor reproducibility of the resistance index suggests that second trimester Doppler assessment of uterine artery flow velocity waveforms may be better described using other semiquantitative methods such as the presence or absence of a diastolic notch.     

Behavior-state–dependent changes in human fetal pulmonary blood flow velocity waveforms

Objective: To establish the influence of fetal behavior states on venous and arterial pulmonary blood flow velocity waveforms in the normally developing term fetus.Methods: The relation between venous and arterial pulmonary blood flow velocity waveforms and fetal behavior states was investigated in 18 normal term fetuses. Recordings of the venous pulmonary blood flow velocity waveforms were obtained just proximal to the entrance in the left atrium, and the arterial pulmonary blood flow velocity waveforms were taken from the most proximal branch of the pulmonary artery in the same lung using color Doppler imaging. Time-averaged peak systolic, peak diastolic, and end-diastolic flow velocity; peak systolic to peak diastolic ratio; pulsatility index; and fetal heart rate were calculated from both venous and arterial Doppler recordings obtained during behavior states 1F (quiet sleep) and 2F (active sleep). Fetal behavior states were determined from combined recordings of fetal eye and body movements.Results: Recordings of sufficient quality for analysis were obtained from ten fetuses. Venous pulmonary blood flow velocity waveforms demonstrated a statistically significant increase in time-averaged peak diastolic and end-diastolic velocity during fetal behavior state 2F. No behavior-state-related changes were observed for the arterial pulmonary blood flow velocity waveform.Conclusion: The data suggest an increased pressure gradient between the pulmonary venous system and the left atrium during behavior state 2F. Flow velocity waveforms from the proximal arterial pulmonary branch are independent of behavioral state.     

Normal fetal Doppler inferior vena cava, transtricuspid, and umbilical artery flow velocity waveforms between 11 and 16 weeks' gestation.

OBJECTIVES: Our objectives were to determine flow velocity waveform patterns in the fetal inferior vena cava and to relate these waveforms to transtricuspid and umbilical artery waveforms and fetal heart rate in early gestation. STUDY DESIGN: Doppler waveforms were recorded in 40 normal fetuses at 11 to 16 weeks of gestation. Only transvaginal scanning was carried out at 11 to 12 weeks and only transabdominal scanning was used at 15 to 16 weeks. RESULTS: The ratio of time velocity integrals of flow from the inferior vena cava during systole and early diastole, the percentage of reverse flow in this vessel, the pulsatility index from the umbilical artery, and the fetal heart rate were negatively correlated with gestational age. Peak E-wave and A-wave velocities and E/A ratios from the transtricuspid waveforms were positively correlated with gestational age. CONCLUSION: Early normal pregnancies are associated with remarkable changes in fetal flow velocity waveforms at both the cardiac and the extracardiac level.     

Uteroplacental Doppler velocimetry during Braxton Hicks' contractions.

Pulsed-wave Doppler ultrasound was used to evaluate the influence of Braxton Hicks' contractions on flow velocity waveforms in the uterine arteries. Flow velocity waveforms were obtained from a standardized site, at the crossing of the uterine artery with the external iliac artery near the uterine wall. Doppler signals were recorded in 16 healthy near-term nulliparous pregnant women. During Braxton Hicks' contractions, a considerable increase in pulsatility index (PI) was found in the uterine arteries increasing from 0.71 +/- 0.21 (mean +/- SD) to 1.14 +/- 0.67 (p < 0.005). Maternal heart rate decreased slightly but significantly during contractions. Despite the high PI values that were found during Braxton Hicks' contractions, a diastolic notch in the flow velocity waveform was never noticed. The findings indicate that during Braxton Hicks' contractions, resistance to blood flow in the uteroplacental circulation is considerably increased.     

正常晚期妊娠胎儿脐动脉,大脑中动脉及腹主动脉血流速度波形与？…

目的 探讨正常妊娠胎儿血流速度波形与胎儿血气的相关性,方法 应用彩色多普勒超声对４５例正常晚期妊娠初孕妇女于剖宫产术时２４小时内进行胎儿脐动脉（ＵＡ）,大脑中动脉（ＭＣＡ）及腹主动脉（ＡｂＡｏ）的血流速度波形（ＦＶＷｓ）检查,计算搏动指数（ＰＩ）,阻力指数（ＲＩ）及收缩期最大血流速度（Ｓ）与舒张末期血流速度（Ｄ）的比值（Ｓ／Ｄ）,同时对剖宫产分娩的新生称立即进行脐动脉血气ｐＨ,二氧化碳分压（ＰＣＯ     

Transvaginal color Doppler assessment of the uteroplacental circulation in early pregnancy

Transvaginal color Doppler was used to investigate the uteroplacental circulation of 45 patients with normal intrauterine pregnancies at 4-18 weeks' gestation. The main uterine artery and the radial and spiral arteries were demonstrated, and characteristic flow velocity waveforms were obtained in more than 90% of cases. The indices of impedance to flow decreased with gestation and there was a progressive fall in these indices from the uterine artery, through the radial, to the spiral artery. Blood velocity in the uterine artery increased exponentially with gestation.     

正常晚期妊娠胎儿脐动脉、大脑中动脉及腹主动脉血流速度波形与胎儿血气相关性探讨

目的探讨正常妊娠胎儿血流速度波形与胎儿血气的相关性。方法应用彩色多普勒超声对４５例正常晚期妊娠初孕妇女于剖宫产术前２４小时内进行胎儿脐动脉（ＵＡ）、大脑中动脉（ＭＣＡ）及腹主动脉（ＡｂＡｏ）的血流速度波形（ＦＶＷｓ）检查，计算搏动指数（ＰＩ）、阻力指数（ＲＩ）及收缩期最大血流速度（Ｓ）与舒张末期血流速度（Ｄ）的比值（Ｓ／Ｄ），同时对剖宫产分娩的新生儿立即进行脐动脉血气ｐＨ、二氧化碳分压（ＰＣＯ２）、氧分压（ＰＯ２）测定。结果ＵＡＲＩ与血ｐＨ、ＰＯ２呈明显负相关（Ｐ＜０．０１，Ｐ＜０．０５），与ＰＣＯ２呈正相关（Ｐ＜０．０５），ＭＣＡＲＩ与血ｐＨ、ＰＯ２呈明显正相关（Ｐ＜０．０１，Ｐ＜０．０５），与ＰＣＯ２呈负相关（Ｐ＜０．０５）。结论产前监测ＵＡ及ＭＣＡ的血流速度波形，可间接了解胎儿血气情况，及时判断胎儿宫内安危的状况。     

Uteroplacental blood flow velocity-time waveforms in normal and complicated pregnancy

Summary. A simple continuous wave Doppler ultrasound system for recording arterial flow velocity waveforms in branches of the uterine artery in the placental bed is described. Twelve normal pregnancies were studied serially from 20 weeks to delivery. The diastolic flow velocity expressed as a percentage of the systolic provides an index of downstream vascular bed resistance and perfusion. This always exceeded 50% in normal pregnancy and there was a small increase with gestational age indicative of a decreasing flow resistance. Of the 91 complicated pregnancies, studied because of potential uteroplacental insufficiency and fetal risk, 25 resulted in the birth of an infant small-for-gestational-age. In 15 the uterine artery flow velocity waveform revealed a pattern of low diastolic flow velocity. It is postulated that these represent a subgroup of growth-retarded fetuses in whom there is reduced uterine artery perfusion. Reduced uterine artery diastolic flow velocity in these patients was associated with reduced umbilical artery diastolic flow velocity on the fetal side of the placenta. In contrast the 10 small-for-gestation infants associated with normal uterine artery waveforms suggest a primary fetal cause. Twelve patients with severe hypertensive disease of pregnancy were studied. Nine were associated with reduced uterine artery diastolic flow velocity (reduced uterine artery perfusion) consistent with vasospasm in the branches of the uterine artery in the placental bed.     

Uteroplacental blood flow velocity-time waveforms in normal and complicated pregnancy

A simple continuous wave Doppler ultrasound system for recording arterial flow velocity waveforms in branches of the uterine artery in the placental bed is described. Twelve normal pregnancies were studied serially from 20 weeks to delivery. The diastolic flow velocity expressed as a percentage of the systolic provides an index of downstream vascular bed resistance and perfusion. This always exceeded 50% in normal pregnancy and there was a small increase with gestational age indicative of a decreasing flow resistance. Of the 91 complicated pregnancies, studied because of potential uteroplacental insufficiency and fetal risk, 25 resulted in the birth of an infant small-for-gestational-age. In 15 the uterine artery flow velocity waveform revealed a pattern of low diastolic flow velocity. It is postulated that these represent a subgroup of growth-retarded fetuses in whom there is reduced uterine artery perfusion. Reduced uterine artery diastolic flow velocity in these patients was associated with reduced umbilical artery diastolic flow velocity on the fetal side of the placenta. In contrast the 10 small-for-gestation infants associated with normal uterine artery waveforms suggest a primary fetal cause. Twelve patients with severe hypertensive disease of pregnancy were studied. Nine were associated with reduced uterine artery diastolic flow velocity (reduced uterine artery perfusion) consistent with vasospasm in the branches of the uterine artery in the placental bed.     

Effects of maternal administration of 3% carbon dioxide on umbilical artery and fetal renal and middle cerebral artery Doppler waveforms.

OBJECTIVE: The null hypothesis is that umbilical, middle cerebral, and renal artery pulsed Doppler velocity waveforms in the normal term fetus may be affected during short-term maternal inhalation of 3% carbon dioxide gas mixture. STUDY DESIGN: Seventy-two observations were made on 14 term fetuses before and during maternal 3% carbon dioxide gas mixture inhalation. The umbilical, middle cerebral, and renal arteries of these fetuses were sampled with pulsed Doppler velocity waveforms and recorded on a strip chart at a preset speed of 50 mm/sec. Doppler waveforms were analyzed for differences in the systolic peak to end-diastolic velocity ratio for these three vascular beds. Peak flow velocity and time velocity integral were also analyzed for the cerebral and renal vascular beds. The data were analyzed with the paired t test. RESULTS: A significant decrease in the systolic-to-diastolic-velocity ratio of the middle cerebral artery occurred with 3% carbon dioxide inhalation (p < 0.02). The other vascular beds had no demonstrable change. CONCLUSION: Transient maternal breathing of 3% carbon dioxide gas mixture selectively causes a decrease in resistance in the fetal cerebral circulation.     

Umbilical artery Doppler flow velocimetry in intrauterine growth restriction and its relation to perinatal outcome.

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 artery between weeks 28 and 41 of pregnancy. Outcomes were compared for the normal Doppler group (16%), the less-severely abnormal group (77%), and the group with severely reduced or absent end-diastolic velocity waveforms (7%). RESULTS: The diagnosis-to-delivery interval was significantly shorter, and the average birth weight and gestational age at delivery were significantly lower, for fetuses with abnormal Doppler velocimetry (showing diminished or severely reduced/absent end-diastolic velocity) than for those in the normal Doppler group. Fetuses with abnormal Doppler velocimetry also had a significantly higher incidence of oligohydramnios, low-birth weight (<10th percentile), and admission to the Neonatal Intensive Care Unit. There were no perinatal deaths among the normal Doppler patients. CONCLUSIONS: Growth-restricted fetuses with normal umbilical artery velocimetry are at significantly lower risk than those with abnormal velocity waveforms, and immediate delivery of the fetus with diminished end-diastolic flow may be unnecessary. Knowing this relationship may be useful in the clinical management of such pregnancies. Doppler surveillance of growth-restricted fetuses supplemented with cardiotocography, preferably combined with biophysical profile testing, results in a prolonged gestational age and acceptable fetal outcome.     

Delayed normalization of uterine artery Doppler waveforms is not a benign phenomenon

OBJECTIVE: To evaluate the pregnancy outcome in patients with abnormal uterine artery Doppler flow velocity waveforms (FVW's) at 19-21 weeks, which were subsequently normal by 24-26 weeks, and to study the effect of low-dose aspirin on these waveforms. DESIGN: The study group consisted of 49 patients who had abnormal uterine artery flow velocity waveforms (FVW's) at 19-21 weeks. These women were initially commenced on 100 mg slow-release aspirin at 20 weeks, which was discontinued at the follow-up visit, after confirming normal uterine artery Doppler FVW. The control group consisted of 730 patients with normal uterine artery Doppler waveforms at 19-21 weeks. The main outcome measures were: small for gestational age (SGA) <10th centile, pre-eclampsia, placental abruption, and perinatal mortality rate (PMR). RESULTS: When compared with the control group, the study group had an increased risk of placental abruption (2% versus 0.27%, P = 0.05) 95% Confidence Intervals CI = 0.01-0.13), low birth weight (3087 versus 3383 gm, P = 0.0003), SGA <10th centile (32.7% versus 11.9%, P 相似文献   

Arterial blood flow velocity waveforms of the pelvis and lower extremities in normal and growth-retarded fetuses.

Serial measurements of femoral artery flow velocity waveforms were made at specified intervals of 3 to 4 weeks from 15 to 20 weeks of gestational age to 35 weeks and 1- to 3-week intervals thereafter until delivery in 12 normal fetuses (group 1A) with pulsed Doppler ultrasonography. The pulsatility index of the femoral artery increased linearly with advancing gestation in all 12 fetuses; this was associated with reverse diastolic flow velocity waveforms. In 30 other normal fetuses (group 1B) whose gestational ages ranged between 16 and 38 weeks (mean +/- SD, 29.5 +/- 5.6 weeks), the femoral artery flow velocity waveforms were analyzed with the external iliac artery, internal iliac artery, and umbilical artery waveforms. No significant difference was observed between the pulsatility index of the external iliac artery and that of the femoral artery (mean +/- SD, 3.7 +/- 1.1 vs 3.7 +/- 1.1). The pulsatility index of the internal iliac artery was significantly higher than that observed in the umbilical artery (mean +/- SD, 1.27 +/- 0.28 vs 1.12 +/- 0.23). The femoral and umbilical artery velocity waveforms also were determined in 20 fetuses with intrauterine growth retardation (group 2), whose gestational ages ranged between 24 and 36 weeks (mean +/- SD, 31 +/- 3.4 weeks). Abnormal femoral artery pulsatility index was recorded in two fetuses who died. Absent or reverse flow of the umbilical artery was recorded in 10 fetuses; four of them died, and four others manifested fetal distress or required admission to the neonatal intensive care unit or both. These preliminary data suggest that the femoral artery pulsatility index cannot be used as an indicator of adverse fetal outcome, whereas absent or reverse flow of the umbilical artery seems to be better correlated with adverse fetal outcome.     

Fetal and neonatal cerebral circulation: a pulsed Doppler study.

We studied the relation between the fetal cerebral circulation and changes in the cerebral circulation directly after birth. With a combined real time ultrasound/pulsed Doppler technique flow velocity waveforms from the fetal umbilical- and carotid-circulation were monitored. Pulsatility Index (PI) was computed and the ratio between Umbilical PI and Carotid PI was calculated. Flow velocity waveforms of the cerebral circulation before birth were related to anterior cerebral artery flow velocity waveforms recorded immediately after birth. The study shows that changes in flow velocity waveforms associated with the intra uterine brain-sparing effect are related to poor obstetrical outcome. Furthermore is shown that the brain-sparing effect in the fetal period is associated with higher PI values in the cerebrovascular circulation in the neonatal period. It is suggested that changes in these PI values, representing changes in cerebrovascular resistance, might be indicative of cerebral ischemia in the neonate.     

Uteroplacental Doppler flow velocity waveform analysis correlates poorly with glycemic control in diabetic pregnant women.

We examined 65 pregnant women with gestational (n = 31) and insulin dependent (n = 34) diabetes mellitus in order to evaluate the clinical usefulness of Doppler flow velocity waveform analysis in these pregnancies. Umbilical and uterine artery flow velocity waveforms were obtained during the third trimester with a continuous wave Doppler device. Quality of maternal glycemic control was evaluated by hemoglobin (Hb) A1 measurements at the time of delivery in 61 patients and by mean capillary blood sugars during the third trimester of pregnancy in four patients. There was no difference in various clinical and Doppler parameters between patients with good glycemic control and those with poor control. In contrast, the same clinical and Doppler parameters were significantly different in patients with preeclampsia than in those without preeclampsia, regardless of glycemic control. There was a poor positive linear correlation (r = 0.30, p less than 0.02) between maternal HbA1 and umbilical artery flow velocity waveforms (systolic/diastolic ratio). Proteinuria correlated better with umbilical artery systolic/diastolic ratio (r = 0.49, p less than 0.001). We conclude that Doppler flow velocity waveform analysis may be clinically useful only in diabetic pregnancies complicated by preeclampsia.     

Doppler sonographic evaluation of exercise-induced blood flow velocity and waveform changes in fetal, uteroplacental and large maternal vessels in pregnant women

The aim of this study was the evaluation by Doppler sonography of blood flow velocity and waveforms in maternal (Femoral artery and vein, carotid artery, uteroplacental) and fetal (Umbilical artery) vessels before and after exercise. Thirteen healthy women with uncomplicated pregnancies (and outcomes) participated in the study between the 36th and 40th gestational week. Each proband underwent 5 exercise tests in a sitting position on a bicycle ergometer with a work load of 100 Watts during 3 minutes. The Doppler measurements were performed with Acuson 128. In the femoral and carotid arteries, peak velocities (systolic and end-diastolic, and for the femoral artery also post-systolic) as well as the mean blood flow velocities were measured. Mean blood flow velocity was also measured in the femoral vein. For the measurements of the arterial diameters, the M-Mode technique, for the femoral vein diameter, the B-Mode technique was used. The uteroplacental and umbilical blood flow waveforms were analysed by the Resistance and Pulsatility Indices. The maternal heart rate as well as systolic and diastolic blood pressures increased after each of the exercise tests. The mean blood flow velocity increased in both the femoral artery and vein while the vessel diameter remained constant. In the carotid artery, however, the velocity remained constant. An analysis of the velocity waveforms for the femoral artery showed in increase in the systolic and end-diastolic velocities as well as a reversal of the post-systolic flow, where the velocity is negative in a state of rest.(ABSTRACT TRUNCATED AT 250 WORDS)