Transvaginal color Doppler study of the uteroplacental circulation in early pregnancy

OBJECTIVE: To compare resistance index (RI) and pulsatility index (PI) values of blood flow in arteries of uteroplacental circulation in normal and threatened abortion first trimester pregnancies. STUDY DESIGN: We have analysed 36 pregnant woman between 5th and 12th weeks of pregnancy--17 patients with threatened abortion as a test group and 19 patients with normal intrauterine pregnancy taken as controls. In all patients transvaginal ultrasonography with pulse color Doppler was performed. The RI and PI values were calculated for blood flow velocity waveforms obtained from uterine artery and its branches--arcuate, radial and spiral arteries. RESULTS: In the test group we have analysed 17 flow velocity waveforms from uterine artery (mean RI 0.852; SD 0.080, mean PI 2.324; SD 0.693), 16 from arcuate artery (mean RI 0.638; SD 0.049, mean PI 1.315; SD 0.064,), 17 from radial artery (mean RI 0.638; SD 0.049, mean PI 1.009; SD 0.177) and 15 from spiral artery (mean RI 0.548; SD 0.068, mean PI 0.804; SD 0.160); in controls we have analysed 16 flow velocity waveforms from uterine artery (mean RI 0.866; SD 0.066, mean PI 2.469; SD 0.618), 17 from arcuate artery (mean RI 0.728; SD 0.123, mean PI 1.352; SD 0.362), 19 from radial artery (mean RI 0.630; SD 0.092, mean PI 1.017; SD 0.261) and 16 from spiral artery (mean RI 0.511; SD 0.100, mean PI 0.760; SD 0.202). CONCLUSION: There was no significant difference in mean RI and PI values between normal and abnormal pregnancies. A gradual statistically significant decrease of RI and PI values during time of pregnancy we have observed only in radial arteries in both groups. For other vessels in the control group the RI and PI values tended to decrease during the time of pregnancy while in the test group some even rose up.     

Effect of dehydroepiandrosterone sulfate on uterine artery flow velocity waveforms in term pregnancy

OBJECTIVE: To investigate the interrelation between estrogen synthesis by the fetoplacental unit and uteroplacental hemodynamics in term pregnancy. METHODS: Transvaginal color Doppler flow imaging and pulsed Doppler ultrasonographic assessments were made on ten normal full-term pregnant women before and 3, 5, 10, 30, and 60 minutes after the administration of a 200-mg intravenous dose of dehydroepiandrosterone sulfate (DHAS) in 20 mL of 5% dextrose. Ten normal full-term pregnant women received 20 mL of 5% dextrose as controls. The pulsatility index (PI) values for the uterine artery, heart rate, and mean arterial pressure were recorded. Plasma estradiol (E2) was measured before and 10 minutes after the infusion. RESULTS: In the DHAS group, uterine artery PI decreased from baseline by 26% (P < .05) after 5 minutes, and the mean reduction was 36% (P < .05) after 10 minutes and 15% (P < .05) after 30 minutes. The PI returned to the baseline value 60 minutes later. In the control group, there was no change in uterine artery PI. No change was found in heart rate or mean arterial blood pressure in the control or DHAS groups. The mean plasma E2 increased from 22.3 +/- 6.6 to 56.2 +/- 24.1 ng/mL (P < .05) 10 minutes after the infusion in DHAS subjects, whereas there was no significant change in plasma E2 in the controls. CONCLUSION: Dehydroepiandrosterone sulfate induces a significant decrease in the uterine artery PI, which suggests a possible decrease in uterine vascular impedance in term pregnancy.     

Use of colour and spectral Doppler ultrasound examination in gynaecology

Objective: To review and sum up the published literature on gynecological Doppler ultrasound examination. Methods: Publications on gynecological Doppler ultrasound examination already known by the author, publications found in the bibliographic database Medline, and publications found in the reference lists of available studies were read, and relevant information was extracted and summarized. Results: Reference data representative of normal findings at transvaginal color and spectral Doppler ultrasound examination of the uterine and ovarian arteries have been established in healthy pre- and post-menopausal women and in normal early pregnancies. Blood flow velocities in the uterine and ovarian arteries change during the normal menstrual cycle and are very different in pre- and post-menopausal women. Lower blood flow velocities and higher pulsatility index (PI) values have been recorded in the ovarian arteries after the menopause. Uterine artery blood flow velocities increase and uterine artery PI values and resistance index (RI) values decrease with gestational age in the first trimester. There is not yet an established role of the gynecological Doppler ultrasound examination in clinical practice. It remains unclear whether the gynecological Doppler ultrasound examination contributes substantially to the clinical management of early pregnancy complications or infertility problems, to the differential diagnosis of pelvic masses or uterine pathology. Conclusions: Large prospective studies-preferably randomized controled trials-are needed to determine the clinical value of the gynecological Doppler ultrasound examination. Copyright 1997 Elsevier Science Ireland Ltd.     

The effects of a copper-intrauterine device on the uterine artery blood flow in regularly menstruating women

The aim of the study was to evaluate the effect of a copper-intrauterine device (IUD) on uterine artery blood flow during the midluteal phase and on the first day of the menstrual cycle using pulsed colour Doppler ultrasonography. Twenty-one regularly menstruating women (18-45 years) who were willing to use copper-IUD contraception participated in the study. The patients were first examined without the IUD in the midluteal phase 6-9 days before the expected onset of menstruation and on the first day of menstruation, after which the IUD was inserted. Three months later the patients were examined again on the corresponding cycle days. The patients estimated the level of dysmenorrhoeic pain with a scoring system. Transvaginal ultrasonography with colour flow imaging was used to measure the pulsatility index (PI) in the uterine arteries. There were no significant changes in the uterine artery blood flow after the insertion of the IUD during menstruation or in the midluteal phase. In patients with increased IUD-related pain during menstruation (n = 5), however, there was a decrease in PI (2.87 +/- 0.52 versus 2.41 +/- 0.23, P = 0.05) after IUD insertion. The decrease in the mean PI was present in all five patients. In conclusion, copper-IUD does not induce any major changes in the resistance of the uterine artery blood flow, although during menstruation in patients with increased menstrual pain after IUD insertion there seems to be a decrease in the uterine artery PI.     

The clinical usefulness of urinary pyridinoline and deoxypyridinoline as potential markers of bone metastasis in patients with prostate cancer

The aims of this study were to investigate the effects of paracentesis on uterine and intraovarian haemodynamics by colour Doppler ultrasound and the influences of repeated paracentesis on pregnancy outcome in severe ovarian hyperstimulation syndrome (OHSS). Forty-one abdominal paracenteses were performed on seven pregnant women with tense ascites and eight thoracocenteses were performed on three pregnant women with pleural effusion. Pulsatility index (PI) and maximum peak systolic velocity (MPSV) of uterine and intraovarian arteries were measured before and after each intervention. The mean PI of uterine arteries was decreased significantly after paracentesis, but not after thoracocentesis. Furthermore, uterine PI was decreased in 13 out of 14 (92.9%) paracenteses with <2500 ml ascites removed, compared with eight out of 13 (61.5%) with >2500 ml ascites removed. After paracentesis, there were no significant changes in the intraovarian PI and MPSV in either group. The 24-hour urine output increased significantly in the paracentesis group, but not in the thoracocentesis group. There were no significant changes in haematocrit and electrolytes as a result of paracentesis. However, gradual falls in serum total proteins and albumin concentrations were observed in all patients after repeated paracentesis, necessitating post-paracentesis albumin infusion. There was no significant difference in miscarriage rates between the two groups. We conclude that repeated abdominal paracentesis increases uterine perfusion and has no adverse effects on pregnancy outcome in severe OHSS. Extraction of 2500 ml of ascitic fluid did not impair uterine perfusion.     

Prevalence and role of anticardiolipin antibodies in Crohn disease

OBJECTIVES: Anticardiolipin antibodies belong to the group of antiphospholid antibodies, and may be seen in association with endothelial damage and recurrent vascular thrombosis. The aim of our study was to determine in patients with Crohn's disease the frequency of anticardiolipin antibodies, and to correlate their presence with clinical activity and treatment of the disease. METHODS: One hundred and thirty-eight sera from patients with Crohn's disease and 118 from age-matched controls were tested for IgG anticardiolipin antibodies. In the Crohn's disease group, we determined whether the patients had a past history of vascular thrombosis, a clinically active intestinal disease, or a current immunosuppressive therapy (steroids or azathioprine). RESULTS: Anticardiolipin antibodies were found significantly more often in patients with Crohn's disease than in controls: 11.0% versus 2.5%, P < 0.02. Three patients with Crohn's disease had a past history of vascular thrombosis, but none of them had anticardiolipin antibodies. The presence of anticardiolipin antibodies was not correlated with the fact that patients had a clinically active disease (P = 0.77), or a current immunosuppressive therapy at the time of the serological test (P = 0.95). CONCLUSIONS: There is a significantly high prevalence of patients with anticardiolipin antibodies during Crohn's disease. The positivity of the test does not seem to be correlated to the existence of a past history of vascular thrombosis, nor to the clinical activity of the disease.     

Effect of antenatal administration of thyrotrophin releasing hormone on fetal flow velocity waveforms

AIM: To determine whether antenatal administration of thyrotrophin releasing hormone (TRH), to promote lung maturation, alters blood flow through the fetal middle cerebral, umbilical artery, or ductus arteriosus and through the maternal uterine arteries. METHODS: The effect of transplacentally administered TRH on the fetal circulation was prospectively evaluated in 30 patients between 24 and 34 weeks' gestation. TRH (400 micrograms) was given to the mother intravenously either as a bolus or an infusion. Fetal effects were determined by measuring the maximum velocity and pulsatility index (PI) in middle cerebral artery, ductus arteriosus, uterine artery and umbilical artery Doppler waveforms. Measurements were made immediately before, and 10 and 60 minutes after maternal TRH administration. RESULTS: Intravenous injection of TRH had no significant effect on PI in the uterine, umbilical, or middle cerebral artery and the ductus arteriosus within 60 minutes of administration in either group. CONCLUSION: The antenatal use of TRH in conjunction with steroids for fetal lung maturity does not affect utero-placental or fetal haemodynamic variables, as measured by Doppler. These findings, therefore, do not support the suggestion that antenatal intravenous administration of TRH either as bolus or infusion may have immediate adverse vascular effects in the fetus.     

Cholera toxin acts as a potent adjuvant for the induction of cytotoxic T-lymphocyte responses with non-replicating antigens

OBJECTIVE: To evaluate the relation between the development of the uteroplacental circulation as assessed by Doppler velocimetry and the maternal blood relaxin concentration. METHODS: Transvaginal color Doppler investigation of the uteroplacental circulation was performed in 42 healthy women at 6-15 weeks' gestation before termination of pregnancy for psychosocial reasons. The resistance index (RI), pulsatility index (PI), and maximum peak velocity were recorded at the level of the main uterine artery, and the presence of intervillous flow was noted. Relaxin, hCG, 17 beta-estradiol (E2), and progesterone levels were measured in maternal venous blood. RESULTS: Limited intervillous flow was noted from 10 weeks' gestation and continuous intervillous flow from 12 weeks. An inverse relation was observed between the circulating levels of both E2 and progesterone and uterine artery RI and PI, whereas the relaxin level correlated positively with uterine RI and PI. Estradiol and progesterone levels also correlated positively with uterine peak systolic velocity and intervillous blood flow. Multiple linear regression analysis indicated that both hormones contributed to the decrease in downstream resistance to uterine blood flow with advancing gestational age, as assessed by uterine RI. In addition, relaxin contributed to the uterine RI and PI and to the intervillous blood flow. CONCLUSION: These data suggest that relaxin, E2, and progesterone may influence the changes in uterine blood flow that occur in early pregnancy. The role played by E2 and progesterone in the development of the uteroplacental circulation may be modulated by relaxin, constituting a novel function for this ovarian peptide.     

Acute effects of cigarette smoking on fetal cardiovascular and uterine Doppler parameters

The purpose of this study was to assess the effects of smoking one cigarette (nicotine mean 0.63 +/- 0.17 mg) on uterine- and foetal cardiovascular Doppler parameters in healthy pregnant smokers. All pregnancies (n = 16; mean gestational age: 36 +/- 4 weeks) had been uneventful and all foetuses were appropriate for gestational age with normal baseline Doppler parameters and normal foetal outcome (birthweight: 3254 +/- 340 grams). Measurements, performed immediately before and after smoking, included pulsatility index (PI) of umbilical artery (UA), middle cerebral artery (MCA), foetal descending aorta and uterine artery as well as maternal and foetal heart rate. The ratio of UA/MCA PI was used to assess centralisation. Changes in foetal cardiac output were determined by: time-velocity integral times heart rate, at aortic and pulmonary valve level. Foetal heart rate (p < 0.0005, paired t-test) and maternal heart rate (p < 0.05) increased significantly. All other parameters did not change significantly. However, in one additional woman with labile hypertension and increased baseline uterine artery PI (1.9), smoking of one cigarette caused a substantial rise in uterine artery PI to 3.25 ten minutes after smoking. Middle cerebral artery PI decreased from 2.2 to 1.18 with an unchanged cardiac output and umbilical artery PI raising the UA/MCA PI ratio from 0.51 to 0.81, suggesting a brain sparing effect. Smoking of one cigarette raised maternal and foetal heart rate. There was no evidence of other cardiovascular effects or centralisation in healthy foetuses of normal pregnancies, but this might not be true in foetus of pathologic pregnancies.     

Anticardiolipin antibodies and osteonecrosis of the femoral head

The current study evaluated the prevalence of anticardiolipin antibodies, which have been associated with thrombotic phenomena, in patients with nontraumatic osteonecrosis of the hip and assessed whether the presence of such antibodies is associated with an increased risk for the development of bone necrosis. Forty consecutive patients (25 men and 15 women) with nontraumatic osteonecrosis of the hip were studied. Their ages ranged from 19 to 56 years (average, 34.3 years). Anticardiolipin antibodies were present in 37.5% (15 of 40) of the tested patients, a significantly higher rate than is seen in healthy subjects, of whom only one of 100 had low titer anticardiolipin antibodies (1%). Six of 40 patients tested positive for immunoglobulin M alone, and six of 40 patients tested positive for immunoglobulin A alone. Three of 40 patients tested positive for immunoglobulin M and immunoglobulin A isotype. The results of the current study indicate an increased incidence of anticardiolipin antibodies in patients with nontraumatic osteonecrosis of the femoral head, which may reflect that anticardiolipin antibodies play a role in the pathogenesis of bone necrosis by predisposing to thrombotic phenomena.     

Intratumoral blood flow in uterine myoma correlated with a lower tumor size and volume, but not correlated with cell proliferation or angiogenesis

OBJECTIVE: To investigate the correlation of intratumoral blood flow in uterine myoma with cell proliferation, angiogenesis, tumor size, and tumor volume. METHODS: Thirty-nine patients who had been scheduled for surgery because of symptomatic uterine myomas were evaluated by transvaginal sonography and color Doppler ultrasound before surgery. The largest dimension of each tumor and the volumes of myomas were determined ultrasonographically. Pulsatility index (PI) was determined by color Doppler ultrasound according to the maximum systolic, end-diastolic, and the mean flow velocities measured within the uterine nodules. After surgery, the paraffin-embedded slides containing representative leiomyoma tissues were stained with hematoxylin and eosin, proliferating cell nuclear antigen for measurement of cell proliferation, and factor VIII for quantitation of microvessel density. The ultrasonographic findings were correlated postoperatively with pathologic findings, and the data were analyzed by simple linear regression and Fisher r to z transformation. RESULTS: Simple regression analysis of the intratumoral PI values on the sizes of myomas showed a negative correlation (r = -0.47, P = .003; n = 39), whereas a less significant correlation between PI values and tumor volumes was observed (r = -0.42, P = .008). In contrast, no statistically significant correlation was observed between the intratumoral PI values and the values of the proliferating cell nuclear antigen index (r = 0.10, P = .547) or microvessel density counts (r = 0.18, P = .282). CONCLUSION: The intratumoral blood flow by transvaginal color Doppler ultrasound correlated with a reduced tumor size and tumor volume, but did not correlate with cell proliferation or angiogenesis.     

Maternal and uteroplacental haemodynamic state in pre-eclamptic patients during spinal anaesthesia for Caesarean section

We have studied the effects of crystalloid (Ringer's acetate 1 litre) preloading and subsequent spinal anaesthesia in 12 pre-eclamptic parturient patients undergoing elective Caesarean section. Maternal placental uterine artery circulation was measured using a pulsed colour Doppler technique with simultaneous measurement of maternal haemodynamic state. Despite preloading, mean maternal systolic arterial pressure (SAP) decreased significantly and marked maternal hypotension (SAP < 80% of baseline value) was recorded in two patients after induction of spinal anaesthesia. Mean central venous pressure increased significantly after preload, but decreased to baseline shortly after induction of spinal anaesthesia. Mean pulsatility index (PI) in the uterine artery did not change during preload or spinal block. In one patient, uterine artery PI increased significantly when SAP decreased to 71% of the baseline value, 14 min after induction of spinal anaesthesia. These results suggest that preload with crystalloid solution does not prevent maternal hypotension in pre-eclamptic patients, and that changes in uterine artery velocity waveforms were minor when SAP was 80% or more of baseline during spinal anaesthesia. These changes did not appear to have any major effect on the clinical condition of the neonate, as assessed by Apgar score and umbilical artery pH values.     

Down-board thinking: what are our next moves?

BACKGROUND: To find out the effectiveness of color Doppler ultrasonography of the uterine arteries in the differentiation of benign molehydatidiforms from malignant gestational trophoblastic disease. METHODS: Prospective study was performed in 32 women who were referred to the Oncology Department with the diagnosis of gestational trophoblastic disease. Uterine artery Doppler studies were made and resistance index for both uterine arteries were calculated. In the follow-up, twelve of these patients required chemotherapy (first group) and 20 of them were treated with only suction curettage (second group). Non parametric Mann Whitney U test was used for the statistical analysis. RESULTS: Median of the lowest uterine artery resistance index were 0.29 for the first group and 0.46 for the second group. Resistance index were significantly lower in the first group (alpha<0.001). Color Doppler study of the uterine arteries is helpful in the differentiation of benign molehydatiforms from malignant gestational trophoblastic disease.     

The relationship between ovarian vascularity and the duration of stimulation in in-vitro fertilization

The role of transvaginal pulsed colour Doppler ultrasound in the assessment of ovarian vascularity was studied in 196 in-vitro fertilization (IVF) cycles. The changes in ovarian blood flow after gonadotrophin-releasing hormone agonist (GnRHa) down-regulation and human menopausal gonadotrophin (HMG) stimulation were determined. The data obtained showed that the ovarian blood flow was significantly improved by oestradiol secretion (P = 0.05) and human chorionic gonadotrophin (HCG) administration (P = 0.003). Folliculogenesis was affected by blood flow supply. The resistance index (RI) value was significantly different (P = 0.05) according to the duration of ovarian stimulation. Patients with a mean RI value >0.56 had a longer stimulation with a significantly lower mean number of oocytes retrieved (P = 0.01) despite the administration of a standard dose of HMG. The RI value is a good indicator of modifications in ovarian vascularization during stimulation. Doppler blood flow measurement could be used to determine the optimal timing for the beginning of HMG administration in patients undergoing ovarian stimulation after down-regulation for IVF treatment.     

Doppler velocimetry of the uterine arteries after hysteroscopic rollerball endometrial ablation

The aim of this study was to document the Doppler indices [pulsatility index (PI) and resistance index (RI)] of the uterine arteries in 30 patients who underwent hysteroscopic rollerball endometrial ablation for dysfunctional uterine bleeding by transvaginal pulsed Doppler sonography, and to reveal whether treatment failures (persistent menometrorrhagia) can be predicted by the blood flow characteristics of the uterine arteries in advance. On the basis of the outcome of patients at the end of the first postoperative year, the Doppler indices of the uterine arteries were meaningful 1 year after the operation when PI (1.32 +/- 0.11; mean +/- SD) and RI (0.71 +/- 0.04) in six menometrorrhagic patients were statistically different from PI (2.19 +/- 0.28; 1.95 +/- 0.36 and 1.82 +/- 0.37) and RI (0.87 +/- 0.06; 0.82 +/- 0.06 and 0.81 +/- 0.04) in normally menstruating, amenorrhoeic and hypomenorrhoeic patients respectively (P < 0.05). On the other hand, the patients who would be menometrorrhagic one year after the operation had a thicker endometrium in the first post-operative month. These findings suggest that the angiogenetic role of the persistent endometrial islands after endometrial ablation needs at some time to be reflected as changes in the Doppler parameters of the uterine arteries.     

Inhibition of protein S by autoantibodies in patients with acquired protein S deficiency

This study was undertaken to analyze antibodies to protein S (PS) in patients with an acquired PS deficiency. Plasma from symptomatic patients with acquired (n = 14) or congenital (n = 10) PS deficiency and 10 healthy donors was screened for PS antibodies by immunoblotting and for anti-phospholipid antibodies. PS antibodies (IgG) were detected in five of the patients with acquired PS deficiency. These antibodies belonged to the G1 and G4 immunoglobulin subclasses. IgG fractions from the same 5 patients were shown to inhibit PS activity. The inhibition of PS activity by the 5 IgG fractions was shown to be time- and dose-dependent and was abolished following incubation with purified PS, while no effect was found after absorption with cardiolipin micelles. In addition, anticardiolipin monoclonal or human purified antibodies, failed to exert significant PS inhibition. These findings demonstrate that anti-PS antibodies are able to inhibit PS activity and that this is independent of anti-phospholipid antibodies. Given the clinical features of the patients, these antibodies should be regarded as an expression of the broad autoimmune syndrome involving the phospholipid-binding plasma proteins.     

Transcranial assessment of maternal cerebral blood flow velocity in patients with pre-eclampsia

BACKGROUND: To clarify the cerebral hemodynamics in pre-eclamptic pregnant women, we investigated the blood flow velocity of the cerebral arteries. METHODS: The mean blood flow velocity and pulsatility index (PI) of the middle cerebral artery (MCA) and internal carotid artery (ICA) in normal pregnant women (n = 35) and pre-eclamptic patients (n = 18) were examined transcranially using pulsed-wave Doppler technique with a 2 MHz probe. In two pre-eclamptic women with post-partum visual disturbance, we examined the mean blood flow velocity and PI of the MCA and ICA every day. RESULTS: The mean blood flow velocity of the MCA in the pre-eclamptic patients (89.7 +/- 20.5 cm/s) was significantly higher than that in the normal pregnant women (53.6 +/- 16.9 cm/s) (p < 0.05). PI of the MCA in the former group (0.67 +/- 0.13) was significantly lower than that in the latter (0.78 +/- 0.02) (p < 0.05). There was no significant difference between these two groups in these variables of the ICA. In the two patients with visual disturbance, the mean blood flow velocity of the MCA was increased before the onset of visual disturbance and decreased gradually following the disappearance of this symptom. In these patients, spasm of the MCA was confirmed by magnetic resonance angiography. CONCLUSIONS: In pre-eclamptic patients, we found increased MCA mean velocity before the onset of visual disturbance. Transcranial Doppler may be useful for the evaluation of cerebral hemodynamics and the prediction of eclampsia.     

Effect of dehydroepiandrosterone sulfate on fetal middle cerebral artery flow velocity waveforms in term pregnancy

OBJECTIVE: To investigate whether bolus injection of dehydroepiandrosterone sulfate (DHAS) is associated with changes in fetal middle cerebral artery flow velocity waveforms in term pregnancy. METHODS: Ten normal full-term pregnant women received the administration of a 200-mg intravenous dose of DHAS in 20 ml of 5% dextrose. Ten normal full term pregnant women received 20 ml 5% dextrose as controls. Color Doppler flow imaging and pulsed Doppler ultrasonographic assessments were made on fetuses in each group before and 10 min, 30 min, 60 min, 90 min. and 120 min after DHAS or dextrose administration. The pulsatility index (PI) values for the middle cerebral artery, and umbilical artery, and fetal heart rate were recorded. RESULTS: In the DHAS group, middle cerebral artery PI decreased from baseline by 24% (p<.05) after 10 min, and the mean reduction was 22% (p<.05) after 30 min. The PI returned to the baseline value 60 min later. In the control group, there was no change in middle cerebral artery PI. No change was found in umbilical artery PI or fetal heart rate in the control or DHAS group. CONCLUSION: DHAS induces a significant decrease in the fetal middle cerebral artery PI, which suggests a possible decrease in fetal cerebral vascular impedance in term pregnancy.     

A study for predicting toxemia of pregnancy by the diastolic notch in pulsed Doppler flow velocity waveforms of the uterine arteries--quantitative analysis of the diastolic notch as uterine arterial index (UTAI)

To investigate the ability of measurement of the diastolic notch in Doppler flow velocimetry to predict development of toxemia of pregnancy, analysis of uteroplacental and fetal blood flow waveforms was performed. The waveforms were analyzed by calculating the resistance index (RI) and the pulsatility index (PI) and were investigated whether diastolic notches existed or not. In the prospective study, the uterine arterial index (UTAI; an index introduced to evaluate the degree of diastolic notch quantitatively) was also calculated. RETROSPECTIVE STUDY: The waveforms in the uterine arteries, the umbilical artery and the fetal vessel (inferior vena cava, descending aorta and middle cerebral artery) were measured in 153 pregnant women. PROSPECTIVE STUDY: Uterine artery velocimetry was performed at 16-23 weeks' gestation in 387 pregnant women. RESULT 1: Subjects with a diastolic notch had significantly higher rates of development of toxemia of pregnancy. Indexes of the fetal blood flow waveforms had no significant correlations with the development of toxemia of pregnancy. RESULT 2: UTAI showed an equivalently high negative predictive value (98.1%) and higher positive predictive value (17.6%) than RI (98.2%, 10.2% respectively) and PI (98.7%, 12.7% respectively). CONCLUSION: UTAI measurement was more useful for predicting toxemia of pregnancy than RI or PI.