First trimester uterine artery Doppler for the prediction of preeclampsia and foetal growth restriction

Evaluation of Conventional and Combined Doppler Parameters in Preeclampsia: Diagnostic and Prognostic Insights

Background: The aim of this study was to examine the relationship between conventional and novel Doppler parameters, including cerebroplacental ratio (CPR), cerebral-placental-uterine ratio (CPUR), umbilical-to-cerebral ratio (UCR), and amniotic-to-umbilical-cerebral ratio (AUCR), with the diagnosis of preeclampsia (PE) and adverse neonatal outcomes in PE cases. Methods: This prospective case-control study was conducted at the Ankara Etlik City Hospital Perinatology Clinic between November 2023 and May 2024. The study population was divided into two groups: Group 1, consisting of 74 patients diagnosed with preeclampsia, and Group 2, consisting of 80 healthy control patients. Composite adverse perinatal outcomes (CANOs) include presence of at least one adverse outcome: 5th-minute APGAR score < 7, transient tachypnea of the newborn (TTN), respiratory distress syndrome (RDS), need for continuous positive airway pressure (CPAP), need for mechanical ventilation, neonatal intensive care unit (NICU) admission, neonatal hypoglycemia, need for phototherapy, intraventricular hemorrhage (IVH), and neonatal sepsis. Results: The CPR, CPUR, and AUCR were significantly lower in the PE group compared to the control group, while the UCR was notably higher in the PE group. Among the combined ratios, the CPUR exhibited the highest diagnostic performance for both PE diagnosis and the prediction of CANOs. Additionally, while the UCR, CPR, and AUCR were significant for PE diagnosis, only AUCR demonstrated a significant association with the prediction of CANOs. Conclusions: Combined Doppler parameters, especially CPUR and AUCR, offer valuable insights into diagnosing PE and predicting CANOs. CPUR demonstrated the highest diagnostic accuracy, underscoring its potential utility in clinical settings.

Prediction of ischemic placental diseases during the first trimester combined test period: a retrospective cohort of low-risk pregnancies in search of the link between parity and disease

Objective: To assess the predictive power of a multifactorial model established on maternal characteristics, placenta-associated plasma protein A (PAPPA), and the mean uterine artery pulsatility index (Ut A PI) levels for the development of ischemic placental diseases (IPD) during the first-trimester combined test (FTCT) period and to evaluate the strength of some generally accepted clinical risk factors.Method: The studied data were obtained from a retrospective cohort of low-risk singleton pregnancies in the FTCT between 1 August 2016 and 1 December 2017. After routine 11-13-week examinations for FTCT, the Ut A PI was measured and stored electronically. The PAPPA multiple of median (MoM) was obtained as a routine component of aneuploidy screening.Results: A sample of 2493 pregnancies with clearly documented outcomes was studied. Early-onset preeclampsia, late-onset preeclampsia and fetal growth restriction (FGR) were observed in 9 (0.36%), 27 (1.08%), and 41 (1.64%) cases, respectively. With optimum cut-off levels of 0.69 for PAPPA MoM and 2.05 for mean Ut A PI and a false positive rate of 4.9%, IPD cases could be predicted with 83.3% sensitivity and 73.7% specificity. Nulliparity, previous abortion in nulliparous women and first pregnancy from second marriage were not independent risk factors. Maternal age, an interval from the last delivery longer than 6 years, and body mass index were found to be independent risk factors.Conclusion: The IPD showed some common and distinct clinical, laboratory and Doppler findings during the FTCT and were predictable with the help of multifactorial analysis. Some widely accepted risk factors could be affected by various confounders. Because of the increased IPD frequencies, parous women with a time interval from the last delivery of 6 years or longer should be screened as a high-risk group for placental dysfunction-related diseases.

Aspirin causes endothelium-dependent vasodilation of resistance arteries from non-gravid and gravid rats

OBJECTIVE

The objective of this study was to understand the effect of acetylsalicylic acid (aspirin) on resistance arteries from mesentery and uterus. During pregnancy, the uterine vasculature undergoes consistent growth to provide sufficient uteroplacental blood flow, a process whose failure is associated with pregnancy complications characterized by high uterine vascular resistance.

METHODS

Uterine arcuate (UA) and mesenteric arteries (MA; diameter <300 µm) isolated from non-gravid, mid-gravid (day 14), and late-gravid rats (day 20) were exposed to aspirin (10^-12 to 10^-5 M). Further, in UA from late-gravid rats, aspirin was evaluated in presence of inhibitors of nitric oxide synthases, cyclooxygenase, cyclic nucleotides (cAMP, cGMP) and BK channels, and also on endothelium-denuded vessels.

RESULTS

Aspirin dilated both UA and MA in a dose dependent manner. Pregnancy increased aspirin vasodilation in MA and UA from mid-gravid rats, an effect that was reduced in vessels from late gravid animals at concentrations >10^-7 M. Further, uterine vasodilation was significantly reduced when the endothelium was removed (p < 0.001), and by inhibitors of nitric oxide synthase (p < 0.001), cyclooxygenase synthase (p < 0.05), cyclic nucleotides cGMP/cAMP and BK channels.

CONCLUSION

This is the first study to show a direct vasodilatory effect of aspirin on rat uterine artery that is mediated by a combination of cellular - primarily endothelial - mechanisms. Our results in UA suggest that the use of aspirin may be effective in enhancing uteroplacental blood flow, while its vasodilation effect on MA may lower peripheral resistance.

First-Trimester Uterine Artery Pulsatility Index and Maternal Serum PAPP-A and PlGF in Prediction of Preeclampsia in Primigravida

Background

Preeclampsia is a heterogeneous disorder affecting different body systems and frequently associated with morbidity and mortality. Early preeclampsia prediction will reduce this associated morbidity and mortality as it will give the chance for frequent maternal and fetal surveillance and application of prophylactic procedures.

Objective

The aim of this work is to evaluate the role of mean pulsatility index (PI) of the uterine arteries and maternal serum concentrations of pregnancy-associated plasma protein A (PAPP-A) and placental growth factor (PlGF) in early preeclampsia prediction in primigravida.

Patients and Methods

Three hundred primigravida attending the antenatal care clinic in Zagazig University Hospitals were included in the study. The mean PI of the uterine arteries was calculated. Maternal serum levels of PAPP-A and PIGF were analyzed by specific immunoassay.

Results

Three hundred women were included in the final analysis, of them 30 patients (10%) suffered from preeclampsia. There was a significant difference between preeclamptic and normal women as regards the mean PI of the uterine arteries and levels of PAPP-A and PIGF at 11-13 weeks. When combining the cutoff levels of the three methods, mean PI of the uterine arteries ≥1.69, PAPP-A assay <0.96 multiple of median (MoM) and PlGF assay <0.91 MoM, the sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy were 56.7, 99.3, 89.5, 95.4 and 67%, respectively.

Conclusion

The combined measurement of maternal serum PAPP-A and PlGF concentrations and mean PI of the uterine arteries at 11-13 weeks of pregnancy may help to predict preeclampsia in primigravida when other parameters of preeclampsia prediction are normal. However, we need more studies on larger and variable populations to evaluate the use of those combined methods in preeclampsia prediction.

Feeding Your Baby In Utero: How the Uteroplacental Circulation Impacts Pregnancy

The utero-placental circulation links the maternal and fetal circulations during pregnancy, ensuring adequate gas and nutrient exchange, and consequently fetal growth. However, our understanding of this circulatory system remains incomplete. Here, we discuss how the utero-placental circulation is established, how it changes dynamically during pregnancy, and how this may impact on pregnancy success, highlighting how we may address knowledge gaps through advances in imaging and computational modeling approaches.

Arterial Resistance in Late First Trimester as a Predictor of Subsequent Pregnancy-Related Hypertension

OBJECTIVES

This study aimed to examine the association between indicators of arterial resistance occurring late in the first trimester and the subsequent development of pregnancy-related hypertension.

METHODS

This study took place between May 2014 and August 2015 and included 329 consecutive women with singleton pregnancies attending the antenatal clinics of a medical college in Karnataka, India, during this period. Pulse pressure (PP) and uterine artery Doppler parameters were recorded between 11-14 gestational weeks. Consequently, women were followed-up until after delivery for subsequent hypertension.

RESULTS

Hypertension occurred more frequently if PP was high (17.6% versus 14.4% of pregnancies without high PP; P = 0.713), if a diastolic notch (DN) was present (15.1% versus 12.8% of pregnancies with an absent DN; P = 0.612) and if the resistive index (RI) was raised (22.2% versus 14.3% of pregnancies without raised RI; P = 0.366). A raised pulsatility index (PI) was significantly associated with hypertension (P = 0.013). The risk of hypertension was approximately seven-fold higher if two or more arterial resistance indicators were used, except with a present DN plus a raised RI or a present DN plus high PP. All arterial resistance indicators showed negative predictability (>85.6%) and good specificity (≥95.0%), except for the presence of a DN. A population-specific cut-off PI value of 1.72 had high negative predictability (92.8%) and good sensitivity (70.8%) and specificity (65.1%).

CONCLUSION

Raised PI in the late first trimester was a significant predictor of hypertension later in pregnancy. A combination of arterial resistance indicators may enhance prediction of subsequent hypertension.

Serum C3 and uterine artery Doppler indices at 14-20 weeks gestation for preeclampsia screening in low-risk primigravidas: A prospective observational study

PROBLEM

Preeclampsia affects 2-10% of human pregnancies with poor screening tests. In order to intervene preventively, high risk population should be identified before the 20th week of pregnancy and by a method not subjected to operator efficiency.

METHODOLOGY

Prospective observational study recruiting 825 low risk primigravidas. Serum C3 and uterine artery Doppler indices were measured at 14-20 weeks.

RESULTS

Serum C3 levels at 14-20 weeks of gestation had a sensitivity 83.3%, specificity 100%, PPV 100% and NPV 98.3% when the cut-off value was 53.1mg/. For the mean RI, the best cut off value found was 0.72 with 100% sensitivity, 99.1% specificity, 92.3% PPV and 100% NPV. For the mean PI the best cut off value was 1.35 with 100% sensitivity, 94.1% specificity, 63.2% PPV and 100% NPV. The combination of serum C3 level and mean uterine artery PI showed 100% sensitivity, 97.4% specificity, 80% PPV and 100% NPV in prediction of PE.

CONCLUSION

Serum C3 levels at 14-20 weeks can be used for prediction of PE with comparable results to uterine artery Doppler indices but has the superiority of being operator independent.

Maternal arterial elasticity in the first trimester as a predictor of birthweight

The early detection of foetal growth restriction and macrosomia is an important goal of modern obstetric care. Aberrant foetal growth is an important cause of perinatal morbidity and mortality. Current modalities for detecting the abnormal foetal growth are often inadequate. Pulse wave analysis using applanation tonometry is a simple and non-invasive test that provides information about the cardiovascular system. Arterial elasticity has previously been implicated in the pathophysiology of pre-eclampsia and cardiovascular disease. Our study examined the relationship between maternal arterial elasticity and birthweight by using pulse wave analysis. We discovered that increased large artery elasticity predicted a larger baby at birth. Large artery elasticity therefore has the potential to act as a useful screening tool which may help in the prediction of women who are at risk of aberrant foetal growth.

Diagnosis and Treatment of Hypertensive Pregnancy Disorders. Guideline of DGGG (S1-Level, AWMF Registry No. 015/018, December 2013)

Purpose: Official guideline published and coordinated by the German Society of Gynecology and Obstetrics (DGGG). Hypertensive pregnancy disorders contribute significantly to perinatal as well as maternal morbidity and mortality worldwide. Also in Germany these diseases are a major course for hospitalization during pregnancy, iatrogenic preterm birth and long-term cardiovascular morbidity. Methods: This S1-guideline is the work of an interdisciplinary group of experts from a range of different professions who were commissioned by DGGG to carry out a systematic literature search of positioning injuries. Members of the participating scientific societies develop a consensus in an informal procedure. Afterwards the directorate of the scientific society approves the consensus. Recommendations: This guideline summarizes the state-of-art for classification, risk stratification, diagnostic, treatment of hypertensive pregnancy disorders.

Predictive accuracy of the first trimester Doppler scan: a meta-study

AIM

To determine sensitivity and cut-off indices of the uterine artery Doppler (UAD) in prediction of preeclampsia and fetal growth restriction (FGR).

METHODS

Seventy-six studies published in 1995-2014, present 298,329 prenatal Doppler screenings performed in nullipara in the first and early second trimesters of singleton pregnancies. The sample is stratified into four groups based on the Doppler sensitivity and specificity indices pertaining to the major clinical endpoints of the cohort.

RESULTS

The FGR diagnostic specificity (r = 0.728) and bilateral notching index (r = 0.803) correlations indicate that the UAD accuracy depends on the placental bed and the screening mode.

CONCLUSIONS

Predictive sensitivity of the UAD increases after 16 weeks + 3 days (115 days) of gestation. The best predictive parameter of preeclampsia and FGR is the placental side uterine artery resistance index which confers to the highest means when the placenta is on the midline (OR 0.9).

The vascular effects of sodium tanshinone IIA sulphonate in rodent and human pregnancy

Danshen, in particular its derivative tanshinone IIA (TS), is a promising compound in the treatment of cardiovascular diseases and has been used for many years in traditional Chinese medicine. Although many actions of TS have been researched, its vasodilator effects in pregnancy remain unknown. There have been a few studies that have shown the ability of TS to reduce blood pressure in women with hypertensive pregnancies; however, there are no studies which have examined the vascular effects of TS in the pregnant state in either normal or complicated pregnancies. Our aim was to determine the vasoactive role of TS in multiple arteries during pregnancy including: rat resistance (mesenteric and uterine) and conduit (carotid) arteries. Further, we aimed to assess the ability of TS to improve uterine blood flow in a rodent model of intrauterine growth restriction. Wire myography was used to assess vascular responses to the water-soluble derivative, sodium tanshinone IIA sulphonate (STS) or to the endothelium-dependent vasodilator, methylcholine. At mid-pregnancy, STS caused direct vasodilation of rat resistance (pEC₅₀ mesenteric: 4.47±0.05 and uterine: 3.65±0.10) but not conduit (carotid) arteries. In late pregnancy, human myometrial arteries responded with a similar sensitivity to STS (pEC₅₀ myometrial: 3.26±0.13). STS treatment for the last third of pregnancy in eNOS^-/- mice increased uterine artery responses to methylcholine (E_max eNOS^-/-: 55.2±9.2% vs. eNOS^-/- treated: 75.7±8.9%, p<0.0001). The promising vascular effects, however, did not lead to improved uterine or umbilical blood flow in vivo, nor to improved fetal biometrics; body weight and crown-rump length. Further, STS treatment increased the uterine artery resistance index and decreased offspring body weight in control mice. Further research would be required to determine the safety and efficacy of use of STS in pregnancy.

The relationship between preeclampsia and intrauterine growth restriction in twin pregnancies

OBJECTIVE

Preeclampsia and intrauterine growth restriction (IUGR) are correlated in singleton pregnancies. The objective of this study was to estimate their relationship in twin pregnancies.

STUDY DESIGN

Cohort of 578 patients with twin pregnancies delivered by 1 maternal fetal medicine practice from 2005-2013. Patients with chronic hypertension, monochorionic-monoamniotic placentation, twin-twin transfusion, and major congenital anomalies were excluded. Standard definitions were used for gestational hypertension and preeclampsia. We defined IUGR as any twin birthweight less than the 5th percentile for gestational age, as well as any twin birthweight less than the 10th percentile for gestational age.

RESULTS

The incidence of preeclampsia was 14.9%, the incidence of birthweight <10% was 50.0%, and the incidence of birthweight <5% was 27.5%. Comparing patients with and without preeclampsia, the rate of birthweight <5th percentile did not differ (27.9% vs 27.4%, P = .929), nor did the rate of birthweight <10th percentile (48.8% vs 50.2%, P = .815). We had 80% power with an alpha error of 5% to show a difference in the likelihood of IUGR <10th percentile from 50% to 66% and a difference in the likelihood of IUGR <5th percentile from 27% to 42% in patients without and with preeclampsia.

CONCLUSION

In patients with twin pregnancy, there is no correlation between preeclampsia and IUGR. This suggests that in twin pregnancies, as opposed to singleton pregnancies, the pathophysiology may differ between these 2 common conditions.

First-trimester prediction of small-for-gestational age neonates incorporating fetal Doppler parameters and maternal characteristics

OBJECTIVE

First-trimester screening for subsequent delivery of a small-for-gestational-age (SGA) infant typically focuses on maternal risk factors and uterine artery (UtA) Doppler. Our aim is to test if incorporation of fetal umbilical artery (UA) and ductus venosus (DV) Doppler improves SGA prediction.

STUDY DESIGN

Prospective screening study of singletons at 11-14 weeks. Maternal characteristics, serum concentrations of pregnancy-associated plasma protein-A (PAPP-A) and free β-human chorionic gonadotropin are ascertained and UtA Doppler, UA, and DV Doppler studies are performed. These parameters are tested for their ability to predict subsequent delivery of a SGA infant.

RESULTS

Among 2267 enrolled women, 191 (8.4%) deliver an SGA infant. At univariate analysis women with SGA neonates are younger, more frequently African-American (AA), nulliparous, more likely to smoke, have lower PAPP-A and free β-human chorionic gonadotropin levels. They have a higher incidence of UtA Doppler bilateral notching, higher mean UtA Doppler-pulsatility index z-scores (P < .001) and UA pulsatility index z-scores (P = .03), but no significant difference in DV-pulsatility index z-scores or in the incidence of abnormal qualitative UA and DV patterns. Multivariate logistic regression analysis identifies nulliparity and AA ethnicity (P < .001), PAPP-A multiple of the median and bilateral notching (P < .05) as determinants of SGA infant. Predictive sensitivity was low; receiver operating characteristic curve analysis yields areas under the curve of 0.592 (95% confidence interval, 0.548-0.635) for the combination of UtA Doppler and UA pulsatility index z-scores.

CONCLUSION

Delivery of a SGA infant is most frequent in nulliparous women of AA ethnicity. Despite the statistical association with UtA Doppler first-trimester SGA prediction is poor and not improved by the incorporation of fetal Doppler.

Comparison of two different sites of measurement for transabdominal uterine artery Doppler velocimetry at 11-13 weeks

OBJECTIVES

To compare the feasibility of two transabdominal approaches for performing first-trimester uterine artery (UtA) Doppler and to evaluate the correlation with pulsatility index (PI) in the second trimester.

METHODS

This was a prospective longitudinal Doppler study of the uterine arteries at 11-13 and 21-22 weeks' gestation. Transabdominal ultrasound and color Doppler were used to measure the UtA-PI of the ascending branch of the uterine artery at the level of the internal cervical os (Site A) and at the level of the apparent crossover with the external iliac artery (Site B) at 11-13 weeks, and at Site B only at 21-22 weeks. In all cases the measured left and right PI were converted to a multiple of the median (MoM) for gestational age, and the intercorrelation between the measurements at different sites and gestational ages was calculated using non-parametric analysis (Spearman's rank correlation).

RESULTS

Satisfactory measurements were obtained at 11-13 weeks from both uterine arteries in all 81 women at Site A and in 50 (62%; 95% CI, 50-72%) at Site B (P < 0.01). Measurements were obtained at Site B at 21-22 weeks in all cases. In the 50 cases with measurements from both sites at 11-13 weeks, the correlation of PI-MoMs between Sites A and B at 11-13 weeks was only moderate (ρ = 0.61). The correlation between first-trimester UtA-PI MoMs at Site A and second-trimester UtA-PI MoMs was stronger than that between first-trimester UtA-PI MoMs at Site B and second-trimester UtA-PI MoMs (ρ = 0.73 vs ρ = 0.47, P < 0.01).

CONCLUSION

Evaluation of UtA-PI at 11-13 weeks can be achieved at the level of the internal cervical os in a greater proportion of women than at the level of the apparent crossover with the external iliac vessels, and the measurements obtained correlate better with second-trimester UtA-PI.

Early detection of maternal risk for preeclampsia

Preeclampsia is one of the leading causes of maternal and fetal morbidity and mortality. New molecular insights offer new possibilities of early diagnosis of elevated maternal risk. Maternal risk factors, biophysical parameters like Doppler examination of the uterine arteries and biochemical parameters allow early risk calculation. Preventive and effective therapeutic agents like acetylsalicylacid can be started in the early second trimester. This article reviews the diagnostic possibilities of early risk calculation to detect women having high risk for preeclampsia and the potential benefits for them, the offspring and health care systems. We provide risk calculation for preeclampsia as an important and sensible part of first trimester screening.