Reference Curve for the Mean Uterine Artery Pulsatility Index in Singleton Pregnancies

Doppler Indices of the Uterine, Umbilical and Fetal Middle Cerebral Artery in Diabetic versus Non-Diabetic Pregnancy: Systematic Review and Meta-Analysis

Background and Objectives: The aim of this study was to assess the differences in Doppler indices of the uterine (Ut), umbilical (UA), and middle cerebral artery (MCA) in diabetic versus non-diabetic pregnancies by conducting a comprehensive systematic review of the literature with a meta-analysis. Materials and Methods: PubMed, Web of Science, and SCOPUS were searched for studies that measured the pulsatility index (PI), resistance index (RI), and systolic/diastolic ratio index (S/D ratio) of the umbilical artery, middle cerebral artery, and uterine artery in diabetic versus non-diabetic pregnancies. Two reviewers independently evaluated the eligibility of studies, abstracted data, and performed quality assessments according to standardized protocols. The standardized mean difference (SMD) was used as a measure of effect size. Heterogeneity was assessed using the I2 statistic. Publication bias was evaluated by means of funnel plots. Results: A total of 62 publications were included in the qualitative and 43 in quantitative analysis. The UA-RI, UtA-PI, and UtA-S/D ratios were increased in diabetic compared with non-diabetic pregnancies. Subgroup analysis showed that levels of UtA-PI were significantly higher during the third, but not during the first trimester of pregnancy in diabetic versus non-diabetic pregnancies. No differences were found for the UA-PI, UA-S/D ratio, MCA-PI, MCA-RI, MCA-S/D ratio, or UtA-RI between diabetic and non-diabetic pregnancies. Conclusions: This meta-analysis revealed the presence of hemodynamic changes in uterine and umbilical arteries, but not in the middle cerebral artery in pregnancies complicated by diabetes.

Anxiety and Uterine Artery Doppler Flow in A Population of Pregnant Women of High Risk Down Syndrome Fetus: A Prospective Cohort Study

BACKGROUND

Fetal exposure to maternal anxiety is associated with low birth weight and maternal stress may be led to constriction of uterine arteries. This study compared the relation of anxiety and uterine artery doppler flow indices in pregnant women with the high and low-risk of Down syndrome.

MATERIALS AND METHODS

This prospective cohort study was conducted among pregnant women in the second trimester that were classified as having a high or low risk according to their prenatal aneuploidy screening outcome. The high risk group underwent amniocentesis. Anxiety was initially assessed using the Spielberger State-Anxiety Inventory (STAI) and uterine artery blood flow indices were evaluated 2 times for the both groups. For the high-risk group first: immediately before amniocentesis and second: after two weeks follow up, when receiving the karyotype results and for the low-risk group in the first admission and two weeks later.

RESULTS

Totally, 375 pregnant women participated in our study that sorted into 2 risk populations based on the aneuploidy screening test, low-risk=176 and high-risk women=199. The high-risk group for Down syndrome amniocentesis showed abnormal results in the 23 cases (23/199). The mean state (P=0.003) and trait (P=0.033) of the Anxiety Inventory scores were significantly different between the groups. Baseline uterine artery indices were no significant difference between the groups. Baseline Uterine artery indices in the high-risk group was significantly different with follow-up (in both positive-amniocentesis and negative amniocentesis sub-groups) indices. Also, there was a weak and significant correlation in the uterine resistance index and STAI scores (P=0.008, r=0.137) during the follow-up period.

CONCLUSION

All pregnant women experienced high level anxiety, especially in the high-risk group that may reduce after confirmation of prenatal aneuploidy screening test and also affects the Doppler indices. For all pregnant women; Stress management and emotional support training is recommended before and during pregnancy.

Cross-modality and in-vivo validation of 4D flow MRI evaluation of uterine artery blood flow in human pregnancy

OBJECTIVES

Clinical assessment of uterine artery (UtA) hemodynamics is currently limited to Doppler ultrasound (US) velocimetry. We have demonstrated previously the feasibility of applying four-dimensional (4D) flow magnetic resonance imaging (MRI) to evaluate UtA hemodynamics during pregnancy, allowing flow quantification of the entire course of the vessel. In this study, we sought to further validate the physiological relevance of 4D flow MRI measurement of UtA blood flow by exploring its association with pregnancy outcome relative to US-based metrics.

METHODS

Recruited into this prospective, cross-sectional study were 87 women with a singleton pregnancy who underwent 4D flow MRI between May 2016 and April 2019 to measure the UtA pulsatility index (MRI-PI) and blood flow rate (MRI-flow, in mL/min). UtA-PI was also measured using US (US-PI). The primary outcome was a composite (COMP) of pre-eclampsia (PE) and/or small-for-gestational-age (SGA) neonate, and secondary outcomes were PE and SGA neonate individually. We assessed the ability of MRI-flow, MRI-PI and US-PI to distinguish between outcomes, and evaluated whether MRI-flow changed as gestation progressed.

RESULTS

Following 4D flow postprocessing and exclusions from the analysis, 74 women had 4D flow MRI data analyzed for both UtAs. Of these, 18 developed a COMP outcome: three developed PE only, 11 had a SGA neonate only and four had both. A comparison of the COMP group vs the no-COMP group found no differences in maternal age, body mass index, nulliparity, gravidity or race. For 66 of the 74 subjects, US data were also available. In these subjects, both median MRI-PI (0.95 vs 0.70; P < 0.01) and median US-PI (0.95 vs 0.73; P < 0.01) were significantly increased in subjects in the COMP group compared with those in the no-COMP group. The UtA blood-flow rate, as measured by MRI, did not increase significantly from the second to the third trimester (median flow (interquartile range (IQR)), 543 (419-698) vs 575 (440-746) mL/min; P = 0.77), but it was significantly lower overall in the COMP compared with the no-COMP group (median flow (IQR), 486 (366-598) vs 624 (457-749) mL/min; P = 0.04). The areas under the receiver-operating-characteristics curves for MRI-flow, MRI-PI and US-PI in predicting COMP were not significantly different (0.694, 0.737 and 0.731, respectively; P = 0.87).

CONCLUSIONS

4D flow MRI can yield physiological measures of UtA blood-flow rate and PI that are associated with adverse pregnancy outcome. This may open up new avenues in the future to expand the potential of this technique as a robust tool with which to evaluate UtA hemodynamics in pregnancy. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal plasma fetuin-A levels in fetal growth restriction: A case-control study

BACKGROUND

Higher Fetuin-A (FA) concentrations were found to be associated with obesity and there is an interest to the relation between maternal FA and pregnancy outcomes.

OBJECTIVE

In this study, our aim was to evaluate the association of maternal plasma levels of FA with fetal growth restriction (FGR).

MATERIALS AND METHODS

41 pregnant women with FGR and 40 controls were recruited in this case-control study between July and November 2015. At the diagnosis of FGR, venous blood samples (10 cc) were obtained for FA analysis.

RESULTS

Maternal plasma FA levels were significantly higher in fetal growth-restricted pregnant women compared with controls (19.3 ± 3.0 ng/ml vs 25.9 ± 6.8 ng/ml, p = 0.001). Area under receiver operating characteristic curve analysis of FA in FGR was 0.815 (95% confidence interval (CI): 0.718-0.912, p < 0.001). The maternal FA levels with values more than 22.5 ng/ml had a sensitivity of about 73.17% (95% CI: 56.79-85.25) and a specificity of about 82.5% (95% CI: 66.64-92.11) with positive and negative predictive values of about 81.08% (95% CI: 64.29-91.45) and 75% (95% CI: 59.35-86.30), respectively. Therefore, the diagnostic accuracy was obtained about 77.78%.

CONCLUSION

The results of this study show higher maternal plasma levels of FA in FGR. Further studies are needed in order to demonstrate the long-term effects of FA in pregnancies complicated with FGR and early prediction of FGR.

[Doppler Sonography during Pregnancy - DEGUM Quality Standards and Clinical Applications]

Doppler sonography is widely established in prenatal medicine and obstetrics and is commonly used in screening for aneuploidy and preeclampsia during the first trimester. More importantly, during the 2nd and 3 rd trimester, it is used in the assessment of fetal health as well as the surveillance of underlying fetal conditions such as IUGR and anemia. Correct use of the method is vital for correct data interpretation and the inferred clinical decision process. Therefore, we aim to provide all users of doppler sonography with a guide for meeting the required quality standards. These quality standards will further be the basis of DEGUM-certified training courses. In the first part, we will introduce the technical principles of the method and potential error sources, vascular disciplines to which the method can be applied, analysis of the spectral curves, patient safety and the needed requirements for successful certification.