Multicenter screening for pre-eclampsia and fetal growth restriction by transvaginal uterine artery Doppler at 23 weeks of gestation

Comparison of competing-risks model with angiogenic factors in midgestation screening for preterm growth-related neonatal morbidity

OBJECTIVES

First, to evaluate the predictive performance for preterm growth-related neonatal morbidity of a high soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) ratio or low PlGF at midgestation and, second, to compare the performance of a high sFlt-1/PlGF ratio or low PlGF with that of the competing-risks model for small-for-gestational age (SGA), utilizing a combination of maternal risk factors, sonographic estimated fetal weight and uterine artery pulsatility index.

METHODS

This was a prospective observational study in women attending for a routine hospital visit at 19-24 weeks' gestation in two maternity hospitals in England. The visit included recording of maternal demographic characteristics and medical history, carrying out an ultrasound scan and measuring serum PlGF and sFlt-1. The primary outcome was delivery < 32 and < 37 weeks' gestation of a SGA neonate with birth weight < 10th or < 3rd percentile, combined with neonatal unit (NNU) admission for ≥ 48 h or a composite of major neonatal morbidity. The detection rates in screening by PlGF < 10th percentile, sFlt-1/PlGF ratio > 90th percentile and the competing-risks model for SGA were estimated and then compared using McNemar's test.

RESULTS

In the study population of 40 241 women, prediction of preterm growth-related neonatal morbidity provided by the competing-risks model for SGA was superior to that of screening by low PlGF concentration or high sFlt-1/PlGF ratio. For example, at a screen-positive rate of 10.0%, as defined by the sFlt-1/PlGF ratio > 90th percentile, the competing-risks model predicted 70.1% (95% CI, 61.0-79.2%) of SGA < 10th percentile and 76.9% (95% CI, 67.6-86.3%) of SGA < 3rd percentile with NNU admission for ≥ 48 h delivered < 32 weeks' gestation. The respective values for SGA with major neonatal morbidity were 73.8% (95% CI, 64.4-83.2%) and 77.9% (95% CI, 68.0-87.8%). These were significantly higher than the respective values of 35.1% (95% CI, 25.6-44.6%), 35.9% (95% CI, 25.3-46.5%), 38.1% (95% CI, 27.7-48.5%) and 39.7% (95% CI, 28.1-51.3%) achieved by the application of the sFlt-1/PlGF ratio > 90th percentile (all P < 0.0001).

CONCLUSION

At midgestation, the prediction of growth-related neonatal morbidity by the competing-risks model for SGA is superior to that of a high sFlt-1/PlGF ratio or low PlGF. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

The role of second trimester uterine artery Doppler in predicting obstetric and neonatal outcomes in abnormal first trimester maternal serum pregnancy-associated plasma protein-A and free β-human chorionic gonadotropin values

AIM

This study aims to determine whether second-trimester uterine artery (UtA) Doppler combined with first-trimester abnormal pregnancy-associated plasma protein-A (PAPP-A) and β-human chorionic gonadotropin (β-Hcg) levels predicts adverse obstetric and neonatal outcomes.

MATERIALS AND METHODS

This study of 289 pregnant women included 196 with normal PAPP-A and free β-HCG values (control group) and 93 with abnormal values (study group) in the first-trimester screening test. Second-trimester UtA Doppler sonography was done in these pregnancies. The perinatal prediction and screening potential of UtA Doppler pulsatility index (PI) parameters were examined in the study group.

RESULTS

UtA PI >95 percentile increased birth before the 37th week by 4.46 times, birth before the 34th week by 7.44 times, preeclampsia risk by 3.25 times, fetal growth restriction (FGR) risk by 4.89 times, and neonatal intensive care unit (NICU) admission rates by 3.66 times in the study group (p < 0.05 for all). UtA PI >95 percentile had 49.2% sensitivity and 82.1% specificity for birth before 37 weeks. For birth before 34 weeks, sensitivity was 80.0% and specificity 65.0%. FGR has 70.5% sensitivity and 67.1% specificity. Screening for preeclampsia has 66.6% sensitivity and 61.9% specificity.

CONCLUSION

Adding UtA Doppler in the second trimester to pregnancies with abnormal PAPP-A and/or free β-Hcg values in the first trimester may be a useful screening method for adverse outcomes.

Bridging the notch: quantification of the end diastolic notch to better predict fetal growth restriction

PURPOSE

We aimed to evaluate several quantitative methods to describe the diastolic notch (DN) and compare their performance in the prediction of fetal growth restriction.

MATERIALS AND METHODS

Patients who underwent a placental scan at 16-26 weeks of gestation and delivered between Jan 2016 and Dec 2020 were included. The uterine artery pulsatility index was measured for all of the patients. In patients with a DN, it was quantified using the notch index and notch depth index. Odds ratios for small for gestational age neonates (defined as birth weight <10th and <5th percentile) were calculated. Predictive values of uterine artery pulsatility, notch, and notch depth index for fetal growth restriction were calculated.

RESULTS

Overall, 514 patients were included, with 69 (13.4%) of them delivering a small for gestational age neonate (birth weight<10th percentile). Of these, 20 (20.9%) had a mean uterine artery pulsatility index >95th percentile, 13 (18.8%) had a unilateral notch, and 11 (15.9%) had a bilateral notch. 16 patients (23.2%) had both a high uterine artery pulsatility index (>95th percentile) and a diastolic notch. Comparison of the performance between uterine artery pulsatility, notch, and notch depth index using receiver operating characteristic curves to predict fetal growth restriction <10th percentile found area under the curve values of 0.659, 0.679, and 0.704, respectively, with overlapping confidence intervals.

CONCLUSION

Quantifying the diastolic notch at 16-26 weeks of gestation did not provide any added benefit in terms of prediction of neonatal birth weight below the 10th or 5th percentile for gestational age, compared with uterine artery pulsatility index.

Placentation and complications of ART pregnancy. An update on the different possible etiopathogenic mechanisms involved in the development of obstetric complications

INTRODUCTION

Infertile couples' percentage is increasing all over the world, especially in Italy, with high number of children born in our country through assisted reproductive techniques (ART). However, pregnancies obtained by ART have increased potential obstetrical risks which could be caused by fetus-placenta unit development, most of all due to placentation's evolution. These can be reassumed into miscarriage, chromosomal abnormalities, preterm delivery, multiple pregnancy, IUGR, placenta previa, abruptio placentae, preeclampsia and hypertensive disorders, postpartum hemorrhage.

METHODS

The aim of this article is to evaluate hypothetic mechanism involved in placentation process and in the etiopathology of ART pregnancies disorders, giving an updating overview of different etiopathogenetic pathways and features. On this scenario, we create an updated review about the etiopathogenesis of abnormal placentation in ART pregnancies.

RESULTS

Several features and different etiopathogenetic characteristic might impact differently such as advanced maternal age, poor ovarian reserve, oocyte quality and causes of subfertility themselves, and the ART techniques itself, as hormonal medical treatments and laboratory techniques such as gamete and embryo laboratory culture, cryopreservation versus fresh ET, number of embryos transferred.

CONCLUSION

To further explore the molecular mechanisms behind placentation in ART pregnancies, further studies are necessary to gain a better understanding of the various aspects involved, particularly those which are not fully comprehended. This could prove beneficial to clinicians in both ART care and obstetric care, as it could help to stratify obstetrical risk and decrease complications in women undergoing ART, as well as perinatal disorders in their children. Correct placentation is essential for a successful pregnancy for both mother and baby.

Preeclampsia Management and Maternal Ophthalmic Artery Doppler Measurements between 19 and 23 Weeks of Gestation

Background: The ophthalmic Doppler is a reliable and impartial way to assess the severity of preeclampsia (PE). The study aimed to assess the potential utility of Doppler measurements of the maternal ophthalmic arteries during the weeks 19-23 of gestation, both independently and in combination with established biomarkers for PE. Methods: A prospective cohort study was conducted involving women who were recruited from a variety of standard appointments, including booking, scanning, and regular prenatal visits. A total of 200 women that were divided into high-risk and low-risk groups for developing PE were involved during the period between April 2023 and November 2023. Results: The ophthalmic ratio had significantly higher values in high-risk patients than in low-risk women (p = 0.000). There was a significant relationship between PSV2/PSV1 and gestational age at birth in women with PE compared to the ones who did not develop PE. Conclusions: An ophthalmic artery Doppler can play a crucial role in the early detection of PE, allowing for timely intervention and management. Incorporating the ophthalmic artery Doppler as a screening tool for PE in Bulgaria has the potential to improve early detection, risk stratification, and overall maternal and fetal health outcomes.

Soluble suppression of tumorigenicity-2 in pregnancy with a small-for-gestational-age fetus and with preeclampsia

OBJECTIVE

Preeclampsia and fetal growth disorders are pregnancy-specific conditions that share common pathophysiological mechanisms. Yet, why some patients develop preeclampsia while others experience fetal growth restriction, or a combination of both clinical presentations, is unknown. We propose that the difference in severity of the maternal inflammatory response can contribute to the clinical phenotypes of preeclampsia vs. small for gestational age (SGA). To assess this hypothesis, we measured maternal plasma concentrations of the soluble isoform of suppression of tumorigenicity-2 (sST2), a member of the interleukin-1 receptor family that buffers proinflammatory responses. Previous reports showed that serum sST2 concentrations rise in the presence of intravascular inflammation and Th1-type immune responses and are significantly higher in patients with preeclampsia compared to those with normal pregnancy. The behavior of sST2 in pregnancies complicated by SGA has not been reported. This study was conducted to compare sST2 plasma concentrations in normal pregnancies, in those with preeclampsia, and in those with an SGA fetus.

METHODS

This retrospective cross-sectional study included women with an SGA fetus (n = 52), women with preeclampsia (n = 106), and those with normal pregnancy (n = 131). Maternal plasma concentrations of sST2 were determined by enzyme-linked immunosorbent assay. Doppler velocimetry of the uterine and umbilical arteries was available in a subset of patients with SGA (42 patients and 43 patients, respectively).

RESULTS

(1) Women with an SGA fetus had a significantly higher median plasma concentration of sST2 than normal pregnant women (p = .008); (2) women with preeclampsia had a significantly higher median plasma concentration of sST2 than those with normal pregnancy (p < .001) and those with an SGA fetus (p < .001); (3) patients with SGA and abnormal uterine artery Doppler velocimetry had a higher median plasma concentration of sST2 than controls (p < .01) and those with SGA and normal uterine artery Doppler velocimetry (p = .02); (4) there was no significant difference in the median plasma sST2 concentration between patients with SGA who had normal uterine artery Doppler velocimetry and controls (p = .4); (5) among patients with SGA, those with abnormal and those with normal umbilical artery Doppler velocimetry had higher median plasma sST2 concentrations than controls (p = .001 and p = .02, respectively); and (6) there was no significant difference in the median plasma sST2 concentrations between patients with SGA who did and those who did not have abnormal umbilical artery Doppler velocimetry (p = .06).

CONCLUSIONS

Preeclampsia and disorders of fetal growth are conditions characterized by intravascular inflammation, as reflected by maternal plasma concentrations of sST2. The severity of intravascular inflammation is highest in patients with preeclampsia.

Unveiling Preeclampsia Prognosis: Uterine Artery Doppler Indices in Low-Risk Pregnancies

Background Anticipating preeclampsia's onset is pivotal in mitigating adverse maternal and perinatal outcomes. This study aims to prognosticate preeclampsia within low-risk pregnancies by evaluating uterine artery Doppler indices within the 14-28 week gestation. Methodology An observational cohort comprising 360 low-risk pregnancies (14-28 weeks gestation) underwent serial uterine artery Doppler assessments at 14-20 and 20-28 weeks. Follow-up was extended to delivery to detect preeclampsia incidence. Results Among 360 participants, 56 (15.5%) developed preeclampsia. Sensitivity values for resistance index (RI), pulsatility index (PI), and bilateral notching were 17.6%, 56.25%, and 71%, respectively, during 14-20 weeks. Similarly, during 20-28 weeks, sensitivities for RI, PI, and bilateral notching were 16.6%, 36.8%, and 55.5%, respectively, with specificity exceeding 90%. Notch depth index (NDI) >0.14 emerged as a better predictor of preeclampsia between both intervals (area under the curve = 0.686 and 0.646). Conclusions Bilateral notching during 14-20 weeks and NDI >0.14 within 14-20 and 20-28 weeks indicate preeclampsia susceptibility in low-risk pregnancies. Conversely, uterine artery Doppler indices at 14-28 weeks effectively rule out preeclampsia development, exhibiting a specificity of >90%.

Prediction of adverse perinatal outcome at midgestation

OBJECTIVES

First, to investigate the association between adverse neonatal outcomes and birth weight and gestational age at delivery. Second, to describe the distribution of adverse neonatal outcomes within different risk strata derived by a population stratification scheme based on the midgestation risk assessment for small-for-gestational-age (SGA) neonates using a competing-risks model.

METHODS

This was a prospective observational cohort study in women with a singleton pregnancy attending a routine hospital visit at 19 + 0 to 23 + 6 weeks' gestation. The incidence of neonatal unit (NNU) admission for ≥ 48 h was evaluated within different birth-weight-percentile subgroups. The pregnancy-specific risk of delivery with SGA < 10th percentile at < 37 weeks was estimated by the competing-risks model for SGA, combining maternal factors and the likelihood functions of Z-score of sonographically estimated fetal weight and uterine artery pulsatility index multiples of the median. The population was stratified into six risk categories: > 1 in 4, > 1 in 10 to ≤ 1 in 4, > 1 in 30 to ≤ 1 in 10, > 1 in 50 to ≤ 1 in 30, > 1 in 100 to ≤ 1 in 50 and ≤ 1 in 100. The outcome measures were admission to the NNU for a minimum of 48 h, perinatal death and major neonatal morbidity. The incidence of each adverse outcome was estimated in each risk stratum.

RESULTS

In the study population of 40 241 women, 0.8%, 2.5%, 10.8%, 10.2%, 19.0% and 56.7% were in the risk strata > 1 in 4, > 1 in 10 to ≤ 1 in 4, > 1 in 30 to ≤ 1 in 10, > 1 in 50 to ≤ 1 in 30, > 1 in 100 to ≤ 1 in 50 and ≤ 1 in 100, respectively. Women in higher-risk strata were more likely to deliver a baby that suffered an adverse outcome. The incidence of NNU admission for ≥ 48 h was highest in the > 1 in 4 risk stratum (31.9% (95% CI, 26.9-36.9%)) and it gradually decreased until the ≤ 1 in 100 risk stratum (5.6% (95% CI, 5.3-5.9%)). The mean gestational age at delivery in SGA cases with NNU admission for ≥ 48 h was 32.9 (95% CI, 32.2-33.7) weeks for risk stratum > 1 in 4 and progressively increased to 37.5 (95% CI, 36.8-38.2) weeks for risk stratum ≤ 1 in 100. The incidence of NNU admission for ≥ 48 h was highest for neonates with birth weight below the 1st percentile (25.7% (95% CI, 23.0-28.5%)) and decreased progressively until the 25th to < 75th percentile interval (5.4% (95% CI, 5.1-5.7%)). Preterm SGA neonates < 10th percentile had significantly higher incidence of NNU admission for ≥ 48 h compared with preterm non-SGA neonates (48.7% (95% CI, 45.0-52.4%) vs 40.9% (95% CI, 38.5-43.3%); P < 0.001). Similarly, term SGA neonates < 10th percentile had significantly higher incidence of NNU admission for ≥ 48 h compared with term non-SGA neonates (5.8% (95% CI, 5.1-6.5%) vs 4.2% (95% CI, 4.0-4.4%); P < 0.001).

CONCLUSIONS

Birth weight has a continuous association with the incidence of adverse neonatal outcomes, which is affected by gestational age. Pregnancies at high risk of SGA, estimated at midgestation, are also at increased risk for adverse neonatal outcomes. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Personalized stratification of pregnancy care for small for gestational age neonates from biophysical markers at midgestation

BACKGROUND

Antenatal identification of pregnancies at high risk of delivering small for gestational age neonates may improve the management of the condition and reduce the associated adverse perinatal outcomes. In a series of publications, we have developed a new competing-risks model for small for gestational age prediction, and we demonstrated that the new approach has a superior performance to that of the traditional methods. The next step in shaping the appropriate management of small for gestational age is the timely assessment of these high-risk pregnancies according to an antenatal stratification plan.

OBJECTIVE

This study aimed to demonstrate the stratification of pregnancy care based on individual patient risk derived from the application of the competing-risks model for small for gestational age that combines maternal factors with sonographic estimated fetal weight and uterine artery pulsatility index at midgestation.

STUDY DESIGN

This was a prospective observational study of 96,678 singleton pregnancies undergoing routine ultrasound examination at 19 to 24 weeks of gestation, which included recording of estimated fetal weight and measurement of uterine artery pulsatility index. The competing-risks model for small for gestational age was used to create a patient-specific stratification curve capable to define a specific timing for a repeated ultrasound examination after 24 weeks. We examined different stratification plans with the intention of detecting approximately 80%, 85%, 90%, and 95% of small for gestational age neonates with birthweight <3rd and <10th percentiles at any gestational age at delivery until 36 weeks; all pregnancies would be offered a routine ultrasound examination at 36 weeks.

RESULTS

The stratification of pregnancy care for small for gestational age can be based on a patient-specific stratification curve. Factors from maternal history, low estimated fetal weight, and increased uterine artery pulsatility index shift the personalized risk curve toward higher risks. The degree of shifting defines the timing for assessment for each pregnancy. If the objective of our antenatal plan was to detect 80%, 85%, 90%, and 95% of small for gestational age neonates at any gestational age at delivery until 36 weeks, the median (range) proportions (percentages) of population examined per week would be 3.15 (1.9-3.7), 3.85 (2.7-4.5), 4.75 (4.0-5.4), and 6.45 (3.7-8.0) for small for gestational age <3rd percentile and 3.8 (2.5-4.6), 4.6 (3.6-5.4), 5.7 (3.8-6.4), and 7.35 (3.3-9.8) for small for gestational age <10th percentile, respectively.

CONCLUSION

The competing-risks model provides an effective personalized continuous stratification of pregnancy care for small for gestational age which is based on individual characteristics and biophysical marker levels recorded at the midgestation scan.

A Comparison of Changes in the Mean Arterial Blood Pressure and Mean Uterine Artery Pulsatility Index from 11-14 to 19-24 + 6 Gestation Weeks in Low-Risk and High-Risk Asian Indian Pregnant Women

Aim  The aim of this study was to determine the changes in the mean arterial blood pressure (MAP) and mean uterine artery (UtA) pulsatility index (PI) from 11-14 to 19-24 + 6 gestation weeks in Asian Indian pregnant women. Methods  Clinical and demographic details, MAP, and mean UtA PI measures were ascertained for pregnant women at 11 to 14 gestation weeks and 19-24 + 6 gestation weeks. Women were categorized as a high-or-low risk for preterm preeclampsia using the Fetal Medicine Foundation algorithm and 1 in 150 cutoff. High-risk pregnant women were recommended low-dose aspirin 150 mg daily at bedtime. Changes in MAP and mean UtA PI were compared for gestational age intervals and high-and-low risk women using nonparametric tests. Results  The study analyzed the results of 1,163 pregnant women. Both MAP (mean difference: 5.14, p  < 0.001) and mean UtA PI (mean difference: 0.14, p  < 0.001) remained significantly higher at the second-trimester assessment in high-risk pregnant women compared to low-risk pregnant women. Seventy-seven (35.16%) of the 219 pregnant women with abnormal mean UtA PI in the first trimester had an abnormal mean UtA PI in the second-trimester assessment. One hundred (10.59%) of the 944 pregnant women with normal mean UtA PI in the first trimester had an abnormal mean UtA PI in the 19-24 + 6 weeks assessment. Seventy-seven pregnant women (6.62% of 1,163 women, 95% confidence interval: 5.33, 8.20) had an abnormal mean UtA PI at both gestation age intervals. High-risk pregnant women taking low-dose aspirin daily showed a larger reduction in mean UtA PI compared to high-risk pregnant women that did not report the use of low-dose aspirin (0.89 vs. 0.62, p <0.001) Conclusion  MAP and mean UtA PI decreased significantly from the first to the second trimester of pregnancy. Sequential assessment of the MAP and mean UtA PI in the first and second trimesters of pregnancy will be useful for fetal radiologists in India to identify a subgroup of women with abnormal mean UtA PI at both trimesters that may need more intense surveillance and follow-up till childbirth.

A mathematical model of vascular and hemodynamics changes in early and late forms of preeclampsia

Preeclampsia-eclampsia syndrome is a leading cause of maternal mortality. The precise etiology of preeclampsia is still not well-defined and different forms exist, including early and late forms or preeclampsia, which may arise via distinctly different mechanisms. Low-dose aspirin administered at the end of the first trimester in women identified as high risk has been shown to reduce the incidence of early, but not late, preeclampsia; however, current risk factors show only fair predictive capability. There is a pressing need to develop accurate descriptions for the different forms of preeclampsia. This paper presents 1D fluid, solid, growth, and remodeling models for pregnancies complicated with early and late forms of preeclampsia. Simulations affirm a broad set of literature results that early forms of preeclampsia are characterized by elevated uterine artery pulsatility index (UA-PI) and total peripheral resistance (TPR) and lower cardiac output (CO), with modestly increased mean arterial blood pressure (MAP) in the first half of pregnancy, with elevation of TPR and MAP beginning at 20 weeks. Conversely, late forms of preeclampsia are characterized by only slightly elevated UA-PI and normal pre-term TPR, and slightly elevated MAP and CO throughout pregnancy, with increased TPR and MAP beginning after 34 weeks. Results suggest that preexisting arterial stiffness may be elevated in women that develop both early forms and late forms of preeclampsia; however, data that verify these results are lacking in the literature. Pulse wave velocity increases in early- and late-preeclampsia, coincident with increases in blood pressure; however, these increases are mainly due to the strain-stiffening response of larger arteries, rather than arterial remodeling-derived changes in material properties. These simulations affirm that early forms of preeclampsia may be associated with abnormal placentation, whereas late forms may be more closely associated with preexisting maternal cardiovascular factors; simulations also highlight several critical gaps in available data.

Combination of Maternal Serum ESM-1 and PLGF with Uterine Artery Doppler PI for Predicting Preeclampsia

OBJECTIVE

This study aimed to determine whether the combination of pregnancy-associated endothelial cell-specific molecule 1 (ESM-1), the placental growth factor (PLGF) in the first- and second-trimester maternal serum, and the uterine artery Doppler pulsatility index (PI) in the second trimester can predict preeclampsia (PE).

METHODS

The serum levels of ESM-1 and PLGF in 33 severe preeclampsia (SPE) patients, 18 mild preeclampsia patients (MPE), and 60 age-matched normal controls (CON) were measured. The Doppler ultrasonography was performed, and the artery pulsatility index (PI) was calculated for the same subjects.

RESULTS

The 2nd PLGF level was significantly lower and the 2nd PI was higher than those in the MPE group. Combining the 2nd PLGF with the 2nd PI yielded an AUC of 0.819 (83.33% sensitivity and 70.00% specificity). In the SPE group, the 1st ESM-1 level and the 2nd PLGF level were significantly lower, and the 2nd ESM-1 level and the 2nd PI were significantly higher in the SPE group. The combination of the 1st ESM-1, the 2nd PLGF, and the 2nd PI yielded an AUC of 0.912 (72.73% sensitivity and 95.00% specificity).

CONCLUSIONS

The 1st ESM-1 and the 2nd PLGF levels and the 2nd PI were associated with PE. The combination of serum biomarkers and the PI improved the screening efficiency of the PE prediction, especially for SPE.

Impact of Marginal and Velamentous Cord Insertion on Uterine Artery Doppler Indices, Fetal Growth, and Preeclampsia

OBJECTIVES

To assess the impact of marginal (MCI) or velamentous (VCI) cord insertion on uterine artery pulsatility index (UtA PI), preeclampsia (PE), and offspring's birthweight (BW).

METHODS

A retrospective cohort study of singleton pregnancies, undergoing routine anomaly scan at 20⁺⁰ -23⁺⁶ gestational weeks, was conducted between 2016 and 2020. The effect of placental cord insertion on BW and UtA mean PI z-scores was assessed using the t test or analysis of variance and post-hoc tests; their association with PE was evaluated with the chi-square test. A multivariate logistic regression model was employed to assess the independent association of placental cord insertion and UtA PI z-score with PE, BW <10th, <5th centile, and intrauterine death (IUD), using specific confounders.

RESULTS

The study population included 4453 pregnancies. Conception via assisted reproductive technology (ART) was associated with increased risk of abnormal cord insertion (odds ratio [OR]: 2.237; 95% confidence interval [CI]: 1.561-3.206; P < .001). Women with MCI/VCI had higher mean UtA PI z-score than those with central/eccentric (0.29 vs 0.01; mean difference: -0.28; 95% CI: -0.399 to -0.165; P < .001). MCI/VCI were associated with higher rates of BW <10th centile (central/eccentric: 16.2% vs MCI: 21.9% vs VCI: 35.7%; P < .001) and BW <5th centile (9.8 vs 15.1 vs 23.2%, respectively; P < .001). No association was identified between MCI/VCI and PE (P = .968). Finally, VCI (aOR: 13.717; 95% CI: 1.576-119.379; P = .018) and increased BMI (aOR: 1.167; 95% CI: 1.071-1.271; P < .001) significantly correlated with IUD.

CONCLUSIONS

Abnormal cord insertion is more common in ART pregnancies. MCI/VCI are associated with higher mean UtA PI and lower BW centile, but not with increased risk of PE.

Midgestation cardiovascular phenotype in women who develop gestational diabetes and hypertensive disorders of pregnancy: comparative study

OBJECTIVE

Women with gestational diabetes mellitus (GDM) and/or hypertensive disorders of pregnancy (HDP) are at increased long-term cardiovascular risk. Mild cardiac functional alterations have been detected in women with GDM or HDP in midgestation, prior to clinical onset of the disease, but these functional alterations have not been found to be useful as screening tools. In contrast, increased impedance to peripheral blood flow, measured by echocardiography or ophthalmic artery Doppler, has been shown to provide incremental value to maternal characteristics for the prediction of pre-eclampsia. However, it is unknown whether similar changes can be detected in women at risk of GDM. In this study, we performed detailed cardiovascular phenotyping in a large, unselected population of women in midgestation to identify similarities and differences in cardiovascular adaptation in women who are at risk of GDM and/or HDP.

METHODS

This was a prospective observational study in women attending for a routine hospital visit at 19 + 1 to 23 + 3 weeks' gestation. This visit included assessment of flow velocity waveforms from the maternal ophthalmic arteries, echocardiography for assessment of maternal cardiovascular function and measurement of uterine artery pulsatility index and serum placental growth factor (PlGF) for assessment of placental perfusion and function. The measured indices were converted to either multiples of the median (MoM) values or deviation from the median (delta) after adjusting for maternal characteristics and elements of medical history. Biomarker delta or MoM values in the GDM and HDP groups were compared with those in the unaffected group using 95% CI and t-tests.

RESULTS

The study population of 5214 pregnancies contained 4429 (84.9%) that were unaffected by GDM or HDP, 509 (9.8%) complicated by GDM without HDP, 41 (0.8%) with GDM and HDP, and 235 (4.5%) with HDP without GDM. In HDP cases, with or without GDM, there was evidence of impaired placentation, with a decrease in PlGF, and increased impedance to flow in the peripheral circulation, suggested by an increase in ophthalmic artery peak systolic velocity (PSV) ratio, peripheral vascular resistance assessed on echocardiography and mean arterial pressure. In the GDM group without HDP, there was no evidence of altered placental perfusion or function and ophthalmic artery PSV ratio was not significantly different from that in the unaffected group; peripheral vascular resistance and mean arterial pressure were increased but to a lesser degree than in the HDP group. In the HDP group, there was an increase in global longitudinal systolic strain and slight increase in isovolumic relaxation time, while in the GDM group, there was an increase in mitral valve E/e', myocardial performance index and global longitudinal systolic strain.

CONCLUSIONS

In midgestation, women who subsequently develop HDP or GDM have a mild subclinical reduction in left ventricular function. In HDP cases, with or without GDM, there is evidence of impaired placentation and all biomarkers of impedance to peripheral blood flow are consistently increased. In contrast, in the GDM group without HDP, biomarkers of placental function are normal and those of impedance to peripheral blood flow are either marginally increased or not significantly different from those in normal pregnancies. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Ophthalmic artery Doppler at 19-23 weeks' gestation in pregnancies that deliver small-for-gestational-age neonates

OBJECTIVES

First, to explore hemodynamic differences between pregnancies delivering a small-for-gestational-age (SGA) neonate in the absence of hypertensive disorders and those that develop pre-eclampsia (PE) or gestational hypertension (GH), by comparing the ophthalmic artery peak systolic velocity (PSV) ratio and first (PSV1) and second (PSV2) PSV at 19-23 weeks' gestation, and second, to compare these pregnancies for markers of placental perfusion and function.

METHODS

This was a prospective observational study in women attending for a routine hospital visit at 19 + 1 to 23 + 3 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination for assessment of fetal anatomy and growth, and measurement of maternal ophthalmic artery PSV ratio, PSV1, PSV2, mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and serum placental growth factor (PlGF). The values of PSV ratio, PSV1, PSV2, MAP, UtA-PI and PlGF were converted to multiples of the median (MoM) or deltas. Mean MoMs or deltas of these biomarkers in the SGA, PE and GH groups were compared with those in the unaffected group. The definition of SGA was birth weight below the 10^th percentile in the absence of PE or GH.

RESULTS

The study population of 5214 pregnancies contained 4375 (83.9%) that were unaffected by SGA, PE or GH, 563 (10.8%) complicated by SGA, 157 (3.0%) with PE and 119 (2.3%) with GH. There were three main findings of the study. First, in the SGA, PE and GH groups, compared with unaffected pregnancies, the PSV ratio delta, PSV2 MoM, MAP MoM and UtA-PI MoM were increased and PlGF MoM was decreased; however, the magnitude of most changes was smaller in the SGA group than in PE and GH groups. Second, in the PE and GH groups, but not in the SGA group, PSV1 MoM was increased. Third, in general, in the pathological pregnancies, the magnitude of deviation of biomarkers from unaffected pregnancies was greater for those delivering at < 37 than at ≥ 37 weeks' gestation.

CONCLUSION

In mid-gestation, pregnancies that subsequently develop hypertensive disorders and those delivering a SGA neonate, compared with unaffected pregnancies, have abnormal uteroplacental measurements and increased maternal ophthalmic artery PSV ratio. These data suggest similar pathophysiology in the two conditions, with evidence of placental dysfunction and increased peripheral vascular resistance, but the magnitude of abnormalities is greater in hypertensive disorders. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

A Review of Roles of Uterine Artery Doppler in Pregnancy Complications

The invasion of trophoblasts into the uterine decidua and decidual vessels is critical for the formation of placenta. The defects of placentation are related to the etiologies of preeclampsia (PE), fetal growth restriction (FGR), and small-for-gestational age (SGA) neonates. It is possible to predict significant vascular events during pregnancy through uterine artery Doppler (UAD). From the implantation stage to the end of pregnancy, detecting changes in uterine and placental blood vessels can provide a favorable diagnostic instrument for pregnancy complications. This review aims to collect literature about the roles of UAD in pregnancy complications. We consider all relevant articles in English from January 1, 1983 to October 30, 2021. Predicting pregnancy complications in advance allows practitioners to carry out timely interventions to avoid or lessen the harm to mothers and neonates. Administering low-dose aspirin daily before 16 weeks of pregnancy can significantly reduce the incidence of pregnancy complications. From early pregnancy to late pregnancy, UAD can combine with other maternal factors, biochemical indicators, and fetal measurement data to identify high-risk population. The identification of high-risk groups can also lessen maternal mortality. Besides, through moderate risk stratification, stringent monitoring for high-risk pregnant women can be implemented, decreasing the incidence of adversities.

Using ultrasound and angiogenic markers from a 19- to 23-week assessment to inform the subsequent diagnosis of preeclampsia

BACKGROUND

A definition of preeclampsia that incorporates the assessment of maternal, fetal, and uteroplacental status would optimize the identification of pregnancies at risk of complications at term gestational age. This definition would include "carrying forward" angiogenic test results from 35 to 36 weeks of gestation to term gestational age. Would this approach still be useful if testing is performed earlier or at a routine midgestation scan and the result is used to inform the diagnosis of preeclampsia that developed thereafter?

OBJECTIVE

This study aimed to evaluate whether fetoplacental assessment at a 19- to 23-week scan could be "carried forward" to contribute to the classification of preeclampsia and improve the detection of women and fetuses at risk of adverse outcomes associated with hypertension.

STUDY DESIGN

In this prospective cohort study of singleton pregnancies at 2 maternity hospitals in England (October 2011 to March 2020), women attending a routine hospital visit at 19 to 23 weeks of gestation underwent an assessment that included history, ultrasonographic estimated fetal weight, Doppler measurements of the pulsatility index in uterine arteries, and serum placental growth factor. Preeclampsia was defined according to various definitions: (1) traditional, based on new-onset proteinuria at ≥20 weeks of gestation; (2) 2013 American College of Obstetricians and Gynecologists; (3) 2018 International Society for the Study of Hypertension in Pregnancy maternal factor; (4) 2018 International Society for the Study of Hypertension in Pregnancy maternal-fetal factor (death or growth restriction), based on ultrasound scans at the 19 0/7 to 23 6/7 week of gestation (an estimated fetal weight of <3rd percentile or estimated fetal weight between the 3rd and 10th percentiles with a uterine artery pulsatility index of >95th percentile); and (5) 2021 International Society for the Study of Hypertension in Pregnancy maternal-fetal factor plus placental growth factor (with abnormal placental growth factor defined as an estimated fetal weight of <5th percentile for gestational age). The detection rates for outcomes of interest (ie, severe maternal hypertension, major maternal morbidity, perinatal mortality or major neonatal morbidity, neonatal intensive care unit admission ≥48 hours, and birthweight of <3rd percentile) ascertained by health record review were compared using the chi-square test. A P value of <.05 was considered statistically significant.

RESULTS

Among 40,241 singleton pregnancies, preeclampsia incidence varied by definition, from lows of 2.6% (traditional) and 3.0% (American College of Obstetricians and Gynecologists) to a high of 3.8% (International Society for the Study of Hypertension in Pregnancy maternal-fetal factor plus placental growth factor). The International Society for the Study of Hypertension in Pregnancy maternal-fetal factor plus placental growth factor definition (vs the traditional) best identified women who developed adverse outcomes: severe hypertension (detection rate: 70.6% vs 52.8%; P<.001), major maternal morbidity (detection rate: 100% vs 87.5%; P=.027), perinatal mortality or major morbidity (detection rate: 84.6% vs 69.5%; P=.004), neonatal intensive care unit admission ≥48 hours (detection rate: 76.6% vs 63.2%;, P=.0002), and birthweight of <3rd percentile (detection rate: 81.3% vs 61.9%; P<.0001]. The detection rates improved, going from the American College of Obstetricians and Gynecologists definition to the International Society for the Study of Hypertension in Pregnancy maternal-fetal factor plus placental growth factor definition, for severe hypertension (11.4%; P=.003), perinatal mortality or major morbidity (10.6%; P=.03), neonatal intensive care unit admission ≥48 hours (8.6%; P=.01), and birthweight of <3rd percentile (16.2%; P<.001). However, going from the International Society for the Study of Hypertension in Pregnancy maternal-fetal factor definition to the International Society for the Study of Hypertension in Pregnancy maternal-fetal factor plus placental growth factor definition, the detection of fetuses with a birthweight of <3rd percentile improved by 7.0% (P=.01), but no other improvement was seen for severe hypertension (1.7%; P=.33), major maternal morbidity (0%), perinatal mortality or major morbidity (4.0%; P=.20), and neonatal intensive care unit admission ≥48 hours (3.2%; P=.17).

CONCLUSION

The criteria for uteroplacental dysfunction (including placental growth factor) from the 19- to 23-week assessment can be used in the assessment of women who are later suspected of having PE, to best identify pregnancies at risk of adverse outcomes.

Longitudinal assessment of spiral artery and intravillous arteriole blood flow and adverse pregnancy outcome

OBJECTIVE

Superb microvascular imaging (SMI) has been shown to improve visualization of small vessels by suppressing global motions while preserving low-flow components, such as the microvessels in the placenta. We sought to determine if SMI-aided visualization of flow velocity waveforms in the spiral arteries (SA) and intravillous fetal arterioles (IVA) could predict fetal growth restriction (FGR), gestational hypertension (GH) and/or pre-eclampsia (PE).

METHODS

This was a prospective longitudinal study of singleton pregnancies without fetal anomaly, receiving prenatal care in one of two medical centers over a 5-year period. Using SMI-aided color Doppler, SA and IVA flow velocity was measured at three timepoints: 11 + 0 to 14 + 0, 18 + 0 to 22 + 6 and 28 + 0 to 34 + 6 weeks of gestation. SA and IVA flow velocity waveforms were reported as resistance indices (RI). RI values were analyzed using multilevel modeling; individual regression curves were estimated and combined to obtain the reference intervals for SA-RI and IVA-RI in uncomplicated pregnancies. The primary clinical outcome was FGR and secondary outcomes were PE and GH. FGR was defined as estimated fetal weight < 10^th percentile. Student's t-test was used to compare deviation from expected RI between normal and complicated pregnancies.

RESULTS

Among 540 pregnancies included in the analysis, 18 (3.3%) had FGR, 31 (5.7%) PE and 61 (11.3%) GH. In uncomplicated pregnancies, the SA-RI decreased progressively with advancing gestation, whereas the IVA-RI increased with gestational age. In the third trimester, the mean SA-RI and IVA-RI values were significantly higher in the FGR group compared with pregnancies that did not develop FGR, while the mean SA-RI was significantly higher in PE compared with non-PE pregnancies. There was no significant difference in mean SA-RI or IVA-RI between pregnancies with vs those without GH at any gestational age. When all three adverse outcomes were combined, SA-RI was significantly higher in pregnancies with these outcomes when compared to uncomplicated pregnancies in the third trimester (mean ± SD, 0.29 ± 0.12 vs 0.26 ± 0.12; P = 0.02). In screening for FGR using SA-RI, the areas under the receiver-operating-characteristics curves (AUC) were 0.68, 0.73 and 0.73 in the first, second and third trimesters, respectively. The respective AUCs for IVA-RI were 0.72, 0.72 and 0.73 for each trimester.

CONCLUSIONS

SA-RI and IVA-RI, measured using SMI technology, were significantly higher in pregnancies at risk for FGR in late gestation. Larger studies are needed to determine if SA and IVA flow are reliable predictors of adverse pregnancy outcome. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Estimated fetal weight at mid-gestation in prediction of pre-eclampsia in singleton pregnancy

OBJECTIVE

To examine the distribution of birth weight according to gestational age in pregnancies complicated by pre-eclampsia (PE) and assess the potential value of sonographic estimated fetal weight (EFW) at mid-gestation as a predictor of PE.

METHODS

The data for this study were derived from prospective screening for adverse obstetric outcome in 93 911 women with a singleton pregnancy attending for routine pregnancy care at 19 + 0 to 24 + 6 weeks' gestation in two UK maternity hospitals. This visit included recording of maternal demographic characteristics and medical history, sonographic EFW and measurement of mean arterial pressure (MAP) and uterine artery pulsatility index (UtA-PI). The distribution of birth weight of pregnancies with and those without PE was assessed. The competing-risks model was used to estimate the individual, patient-specific risk of delivery with PE at < 32 and < 37 weeks' gestation and at any gestational age. The areas under the receiver-operating-characteristics curves and detection rates (DRs) of delivery with PE, at a 10% false-positive rate (FPR), were assessed for various combinations of maternal risk factors, EFW, MAP and UtA-PI. McNemar's test was used to determine the significance of difference in DR at a 10% FPR between screening with vs without EFW.

RESULTS

The study population contained 2843 (3.0%) pregnancies that subsequently developed PE, including 148 (0.2%) that delivered with PE at < 32 weeks' gestation and 654 (0.7%) that delivered with PE at < 37 weeks. Birth weight was < 10^th percentile in 82% of pregnancies with PE delivering at < 32 weeks' gestation and this decreased to 21% of those with PE delivering at ≥ 37 weeks. In screening for delivery with PE at < 32 and < 37 weeks' gestation, the DR, at a 10% FPR, achieved by maternal risk factors (51% and 46%, respectively) was improved by addition of EFW (69% and 51%, respectively). Similarly, addition of EFW improved the performance of screening by a combination of maternal risk factors and MAP from 72% to 80% for PE < 32 weeks and from 57% to 60% for PE < 37 weeks. EFW did not improve the predictive performance of screening by a combination of maternal risk factors, MAP and UtA-PI.

CONCLUSIONS

In pregnancies complicated by preterm PE, a high proportion of neonates are small-for-gestational age, and sonographic EFW at mid-gestation can improve the prediction of early and preterm PE provided by maternal risk factors and MAP but not the prediction provided by a combination of maternal risk factors, MAP and UtA-PI. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Could Aspirin Treatment Modify the Assessment of the Uterine Arteries?

OBJECTIVE

 To analyze whether acetylsalicylic (ASA) intake modifies the mean uterine arteries pulsatility index (UtA-PI) at the 2^nd or 3^rd trimester in a cohort of pregnant women with abnormal mean UtA-PI at between 11 and 14 weeks of gestation.

METHODS

 This is a retrospective cohort study. Singleton pregnancies with abnormal mean UtA-PI at between 11 and 14 weeks of gestation were studied. The participants were divided into 3 groups: 1) If the participant did not take ASA during pregnancy; 2) If the participant took ASA before 14 weeks of gestation; and 3) If the participant took ASA after 14 weeks of gestation. The mean UtA-PI was evaluated at the 2^nd and 3^rd trimesters, and it was considered to improve when it decreased below the 95^th percentile. The prevalence ratio (PR) and the number needed to treat (NNT) were calculated.

RESULTS

 A total of 72 participants with a mean UtA-PI > 95^th percentile at the 1^st trimester of gestation were evaluated. Out of the 18 participants who took ASA, 8 participants started it before 14 weeks of gestation and 10 after. A total of 33.3% of these participants had improved the mean UtA-PI at the 2^nd and 3^rd trimesters of gestation, although it was not statistically significant (p = 0.154). The prevalence ratio was 0.95 (95% confidence interval [CI]: 0.31-1.89), but between the 1^st and 2^nd trimesters of gestation, the PR was 0.92 (95%CI: 0.21-0.99) and it was statistically significant.

CONCLUSION

 The present work demonstrates a modification of the mean UtA-PI in participants who took ASA compared with those who did not. It is important to check if ASA can modify the normal limits of uterine arteries because this could have an impact on surveillance.

Second-trimester contingent screening for small-for-gestational-age neonate

OBJECTIVES

First, to investigate the additive value of second-trimester placental growth factor (PlGF) for the prediction of a small-for-gestational-age (SGA) neonate. Second, to examine second-trimester contingent screening strategies.

METHODS

This was a prospective observational study in women with singleton pregnancy undergoing routine ultrasound examination at 19-24 weeks' gestation. We used the competing-risks model for prediction of SGA. The parameters for the prior model and the likelihoods for estimated fetal weight (EFW) and uterine artery pulsatility index (UtA-PI) were those presented in previous studies. A folded-plane regression model was fitted in the dataset of this study to describe the likelihood of PlGF. We compared the prediction of screening by maternal risk factors against the prediction provided by a combination of maternal risk factors, EFW, UtA-PI and PlGF. We also examined the additive value of PlGF in a policy that uses maternal risk factors, EFW and UtA-PI.

RESULTS

The study population included 40 241 singleton pregnancies. Overall, the prediction of SGA improved with increasing degree of prematurity, with increasing severity of smallness and in the presence of coexisting pre-eclampsia. The combination of maternal risk factors, EFW, UtA-PI and PlGF improved significantly the prediction provided by maternal risk factors alone for all the examined cut-offs of birth weight and gestational age at delivery. Screening by a combination of maternal risk factors and serum PlGF improved the prediction of SGA when compared to screening by maternal risk factors alone. However, the incremental improvement in prediction was decreased when PlGF was added to screening by a combination of maternal risk factors, EFW and UtA-PI. If first-line screening for a SGA neonate with birth weight < 10^th percentile delivered at < 37 weeks' gestation was by maternal risk factors and EFW, the same detection rate of 90%, at an overall false-positive rate (FPR) of 50%, as that achieved by screening with maternal risk factors, EFW, UtA-PI and PlGF in the whole population can be achieved by reserving measurements of UtA-PI and PlGF for only 80% of the population. Similarly, in screening for a SGA neonate with birth weight < 10^th percentile delivered at < 30 weeks, the same detection rate of 90%, at an overall FPR of 14%, as that achieved by screening with maternal risk factors, EFW, UtA-PI and PlGF in the whole population can be achieved by reserving measurements of UtA-PI and PlGF for only 70% of the population. The additive value of PlGF in reducing the FPR to about 10% with a simultaneous detection rate of 90% for a SGA neonate with birth weight < 3^rd percentile born < 30 weeks, is gained by measuring PlGF in only 50% of the population when first-line screening is by maternal factors, EFW and UtA-PI.

CONCLUSIONS

The combination of maternal risk factors, EFW, UtA-PI and PlGF provides effective second-trimester prediction of SGA. Serum PlGF is useful for predicting a SGA neonate with birth weight < 3^rd percentile born < 30 weeks after an inclusive assessment by maternal risk factors and biophysical markers. Similar detection rates and FPRs can be achieved by application of contingent screening strategies. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal Cardiac Function at Midgestation and Development of Preeclampsia

BACKGROUND

Preeclampsia (PE) is an independent risk factor for adverse maternal cardiovascular outcomes. The role of maternal cardiac function in the pathophysiology of PE remains unclear.

OBJECTIVES

This study sought to describe differences in cardiac function at midgestation between women who develop PE and those with uncomplicated pregnancy and to establish whether routine cardiac assessment at midgestation can improve performance of screening for PE achieved by established biomarkers.

METHODS

Mean arterial pressure was measured, medical history was obtained, and left ventricular (LV) systolic and diastolic functions were assessed using standard echocardiography and speckle tracking imaging. Uterine artery pulsatility index and serum placental growth factor and soluble fms-like tyrosine kinase-1 were measured.

RESULTS

In 4,795 pregnancies, 126 (2.6%) developed PE. Following multivariable analysis, peripheral vascular resistance was significantly higher and LV global longitudinal systolic strain, ejection fraction, cardiac output, and left atrial area were mildly lower in women who developed PE compared to those who did not. There was a weak association between maternal cardiovascular indices and biomarkers of placental perfusion and function. Cardiac indices did not improve the performance of screening for PE on top of maternal risk factors, mean arterial pressure, and biomarkers of placental perfusion and function.

CONCLUSION

Women who develop PE have an increase in peripheral vascular resistance and a mild reduction in LV functional cardiac indices long before PE development. However, cardiac indices do not improve the performance of screening for PE; thus, their routine clinical use is not advocated.

Development and validation of model for prediction of placental dysfunction-related stillbirth from maternal factors, fetal weight and uterine artery Doppler at mid-gestation

OBJECTIVE

To examine the performance of a model combining maternal risk factors, uterine artery pulsatility index (UtA-PI) and estimated fetal weight (EFW) at 19-24 weeks' gestation, for predicting all antepartum stillbirths and those due to impaired placentation, in a training dataset used for development of the model and in a validation dataset.

METHODS

The data for this study were derived from prospective screening for adverse obstetric outcome in women with singleton pregnancy attending for routine pregnancy care at 19 + 0 to 24 + 6 weeks' gestation. The study population was divided into a training dataset used to develop prediction models for placental dysfunction-related antepartum stillbirth and a validation dataset to which the models were then applied. Multivariable logistic regression analysis was used to develop a model based on a combination of maternal risk factors, EFW Z-score and UtA-PI multiples of the normal median. We examined the predictive performance of the model by, first, the ability of the model to discriminate between the stillbirth and live-birth groups, using the area under the receiver-operating-characteristics curve (AUC) and the detection rate (DR) at a fixed false-positive rate (FPR) of 10%, and, second, calibration by measurements of calibration slope and intercept.

RESULTS

The study population of 131 514 pregnancies included 131 037 live births and 477 (0.36%) stillbirths. There are four main findings of this study. First, 92.5% (441/477) of stillbirths were antepartum and 7.5% (36/477) were intrapartum, and 59.2% (261/441) of antepartum stillbirths were observed in association with placental dysfunction and 40.8% (180/441) were unexplained or due to other causes. Second, placental dysfunction accounted for 80.1% (161/201) of antepartum stillbirths at < 32 weeks' gestation, 54.2% (52/96) at 32 + 0 to 36 + 6 weeks and 33.3% (48/144) at ≥ 37 weeks. Third, the risk of placental dysfunction-related antepartum stillbirth increased with increasing maternal weight and decreasing maternal height, was 3-fold higher in black than in white women, was 5.5-fold higher in parous women with previous stillbirth than in those with previous live birth, and was increased in smokers, in women with chronic hypertension and in parous women with a previous pregnancy complicated by pre-eclampsia and/or birth of a small-for-gestational-age baby. Fourth, in screening for placental dysfunction-related antepartum stillbirth by a combination of maternal risk factors, EFW and UtA-PI in the validation dataset, the DR at a 10% FPR was 62.3% (95% CI, 57.2-67.4%) and the AUC was 0.838 (95% CI, 0.799-0.878); these results were consistent with those in the dataset used for developing the algorithm and demonstrate high discrimination between affected and unaffected pregnancies. Similarly, the calibration slope was 1.029 and the intercept was -0.009, demonstrating good agreement between the predicted risk and observed incidence of placental dysfunction-related antepartum stillbirth. The performance of screening was better for placental dysfunction-related antepartum stillbirth at < 37 weeks' gestation compared to at term (DR at a 10% FPR, 69.8% vs 29.2%).

CONCLUSIONS

Screening at mid-gestation by a combination of maternal risk factors, EFW and UtA-PI can predict a high proportion of placental dysfunction-related stillbirths and, in particular, those that occur preterm. Such screening provides poor prediction of unexplained stillbirth or stillbirth due to other causes. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Predictive performance for placental dysfunction related stillbirth of the competing risks model for small for gestational age fetuses

OBJECTIVES

First, to examine the predictive performance for placental dysfunction related stillbirths of the competing risks model for small for gestational age (SGA) fetuses based on a combination of maternal risk factors, estimated fetal weight (EFW) and uterine artery pulsatility index (UtA-PI); and second, to compare the performance of this model to that of stillbirth-specific model utilizing the same biomarkers and to the Royal College of Obstetricians and Gynecologists (RCOG) guideline for the investigation and management of the SGA fetus.

DESIGN

Prospective observational study.

SETTING

Two UK maternity hospitals.

POPULATION

131,514 women with singleton pregnancies attending for routine ultrasound examination at 19-24 weeks' gestation.

METHODS

The predictive performance for stillbirth achieved by three models was compared. Main outcome measure Placental dysfunction related stillbirth.

RESULTS

At 10% false positive rate, the competing risks model predicted 59%, 66% and 71% of placental dysfunction related stillbirths, at any gestation, at <37 weeks and at <32 weeks, respectively, which were similar to the respective figures of 62%, 70% and 73% for the stillbirth-specific model. At a screen positive rate of 21.8 %, as defined by the RCOG guideline, the competing risks model predicted 71%, 76% and 79% of placental dysfunction related stillbirths at any gestation, at <37 weeks and at <32 weeks, respectively, and the respective figures for the RCOG guideline were 40%, 44% and 42%.

CONCLUSION

The predictive performance for placental dysfunction related stillbirths by the competing risks model for SGA was similar to the stillbirth-specific model and superior to the RCOG guideline.

Vibrational Spectroscopy: A Valuable Screening and Diagnostic Tool for Obstetric Disorders?

Preeclampsia (PE) is a common obstetric disorder typically affecting 2–8% of all pregnancies and can lead to several adverse obstetric outcomes for both mother and fetus with the greatest burden of severe outcomes in low middle-income countries (LMICs), therefore, screening for PE is vital. Globally, screening is based on maternal characteristics and medical history which are nonspecific for the disorder. In 2004, the World Health Organization acknowledged that no clinically useful test was able to predict the onset of PE, which prompted a universal search for alternative means of screening. Over the past decade or so, emphasis has been placed on the use of maternal characteristics in conjunction with biomarkers of disease combined into predictive algorithms, however these are yet to transition into the clinic and are cost prohibitive in LMICs. As a result, the screening paradigm for PE remains unchanged. It is evident that novel approaches are needed. Vibrational spectroscopy, specifically Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR), could provide better alternatives suited for implementation in low resource settings as no specialized reagents are required for conventional approaches and there is a drive to portable platforms usable in both urban and rual community settings. These techniques are based on light scattering and absorption, respectively, allowing detailed molecular analysis of samples to produce a unique molecular fingerprint of diseased states. The specificity of vibrational spectroscopy might well make it suited for application in other obstetric disorders such as gestational diabetes mellitus and obstetric cholestasis. In this review, we summarize current approaches sought as alternatives to current screening methodologies and introduce how vibrational spectroscopy could offer superior screening and diagnostic paradigms in obstetric care. Additionally, we propose a real benefit of such tools in LMICs where limited resources battle the higher prevalence of obstetric disorders.

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.

Competing risks model for prediction of small-for-gestational-age neonates from biophysical markers at 19 to 24 weeks' gestation

BACKGROUND

Antenatal identification of women at high risk to deliver small-for-gestational-age neonates may improve the management of the condition. The traditional but ineffective methods for small-for-gestational-age screening are the use of risk scoring systems based on maternal demographic characteristics and medical history and the measurement of the symphysial-fundal height. Another approach is to use logistic regression models that have higher performance and provide patient-specific risks for different prespecified cutoffs of birthweight percentile and gestational age at delivery. However, such models have led to an arbitrary dichotomization of the condition; different models for different small-for-gestational-age definitions are required and adding new biomarkers or examining other cutoffs requires refitting of the whole model. An alternative approach for the prediction of small-for-gestational-age neonates is to consider small for gestational age as a spectrum disorder whose severity is continuously reflected in both the gestational age at delivery and z score in birthweight for gestational age.

OBJECTIVE

This study aimed to develop a new competing risks model for the prediction of small-for-gestational-age neonates based on a combination of maternal demographic characteristics and medical history with sonographic estimated fetal weight, uterine artery pulsatility index, and mean arterial pressure at 19 to 24 weeks' gestation.

STUDY DESIGN

This was a prospective observational study of 96,678 women with singleton pregnancies undergoing routine ultrasound examination at 19 to 24 weeks' gestation, which included recording of estimated fetal weight, uterine artery pulsatility index, and mean arterial pressure. The competing risks model for small for gestational age is based on a previous joint distribution of gestational age at delivery and birthweight z score, according to maternal demographic characteristics and medical history. The likelihoods of the estimated fetal weight, uterine artery pulsatility index, and mean arterial pressure were fitted conditionally to both gestational age at delivery and birthweight z score and modified the previous distribution, according to the Bayes theorem, to obtain an individualized posterior distribution for gestational age at delivery and birthweight z score and therefore patient-specific risks for any desired cutoffs for birthweight z score and gestational age at delivery. The model was internally validated by randomly dividing the data into a training data set, to obtain the parameters of the model, and a test data set, to evaluate the model. The discrimination and calibration of the model were also examined.

RESULTS

The estimated fetal weight was described using a regression model with an interaction term between gestational age at delivery and birthweight z score. Folded plane regression models were fitted for uterine artery pulsatility index and mean arterial pressure. The prediction of small for gestational age by maternal factors was improved by adding biomarkers for increasing degree of prematurity, higher severity of smallness, and coexistence of preeclampsia. Screening by maternal factors with estimated fetal weight, uterine artery pulsatility index, and mean arterial pressure, predicted 41%, 56%, and 70% of small-for-gestational-age neonates with birthweights of <10th percentile delivered at ≥37, <37, and <32 weeks' gestation, at a 10% false-positive rate. The respective rates for a birthweight of <3rd percentile were 47%, 65%, and 77%. The rates in the presence of preeclampsia were 41%, 72%, and 91% for small-for-gestational-age neonates with birthweights of <10th percentile and 50%, 75%, and 92% for small-for-gestational-age neonates with birthweights of <3rd percentile. Overall, the model was well calibrated. The detection rates and calibration indices were similar in the training and test data sets, demonstrating the internal validity of the model.

CONCLUSION

The performance of screening for small-for-gestational-age neonates by a competing risks model that combines maternal factors with estimated fetal weight, uterine artery pulsatility index, and mean arterial pressure was superior to that of screening by maternal characteristics and medical history alone.

Pathological AT1R-B2R Protein Aggregation and Preeclampsia

Preeclampsia is one of the most frequent and severe complications of pregnancy. Symptoms of preeclampsia usually occur after 20 weeks of pregnancy and include hypertension and kidney dysfunction with proteinuria. Up to now, delivery of the infant has been the most effective and life-saving treatment to alleviate symptoms of preeclampsia because a causative treatment does not exist, which could prolong a pregnancy complicated with preeclampsia. Preeclampsia is a complex medical condition, which is attributed to a variety of different risk factors and causes. Risk factors account for insufficient placentation and impaired vasculogenesis and finally culminate in this life-threatening condition of pregnancy. Despite progress, many pathomechanisms and causes of preeclampsia are still incompletely understood. In recent years, it was found that excessive protein complex formation between G-protein-coupled receptors is a common sign of preeclampsia. Specifically, the aberrant heteromerization of two vasoactive G-protein-coupled receptors (GPCRs), the angiotensin II AT1 receptor and the bradykinin B2 receptor, is a causative factor of preeclampsia symptoms. Based on this knowledge, inhibition of abnormal GPCR protein complex formation is an experimental treatment approach of preeclampsia. This review summarizes the impact of pathological GPCR protein aggregation on symptoms of preeclampsia and delineates potential new therapeutic targets.

Contingent screening in stratification of pregnancy care based on risk of pre-eclampsia at 19-24 weeks' gestation

OBJECTIVE

To explore the possibility of carrying out routine screening for pre-eclampsia (PE) with delivery at < 28, < 32, < 36 weeks' gestation by maternal factors, uterine artery pulsatility index (UtA-PI) and mean arterial pressure (MAP) in all pregnancies and reserving measurements of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) for only a subgroup of the population.

METHODS

This was a prospective observational study in two UK maternity hospitals involving women with singleton pregnancy attending for routine assessment at 19-24 weeks' gestation. The improvement in performance of screening for PE, at fixed risk cut-offs, by the addition of serum PlGF and sFlt-1 to screening by maternal factors, UtA-PI and MAP, was estimated. We examined a policy of contingent screening in which biochemical testing was reserved for only a subgroup of the population. The main outcome measures were the additional contribution of PlGF and sFlt-1 to the performance of screening for PE and the proportion of the population requiring measurement of PlGF and sFlt-1 for maximum performance of screening.

RESULTS

The study population included 37 886 singleton pregnancies. At each risk cut-off, the highest detection rates for delivery with PE and the lowest screen-positive rates were achieved in screening with maternal factors, UtA-PI, MAP, PlGF and sFlt-1. The maximum performance by such screening was also achieved by contingent screening in which PlGF and sFlt-1 were measured in only about 40% of the population.

CONCLUSION

The performance of screening for PE by a combination of maternal factors, UtA-PI and MAP is improved by measurement of PlGF and sFlt-1 in about 40% of the population. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Doppler ultrasound in pregnancy - quality requirements of DEGUM and clinical application (part 2)

This second part on Doppler sonography in prenatal medicine and obstetrics reviews its clinical applications. While this has not become the initially anticipated screening tool, it is used for the diagnosis and surveillance of a variety of fetal pathologies. For example, the sonography-based determination of uterine artery blood flow indices is an important parameter for the first trimester multimodal preeclampsia risk assessment, increasing accuracy and providing indication for the prophylactic treatment with aspirin. It also has significant implications for the diagnosis and surveillance of growth-restricted fetuses in the second and third trimesters through Doppler-sonographic analysis of umbilical artery, middle cerebral artery and ductus venosus. Here, especially the hemodynamics of the ductus venosus provides a critical criterium for birth management of severe, early-onset FGR before 34 + 0 weeks of gestation. Further, determination of maximum blood flow velocity of the middle cerebral artery is a central parameter in fetal diagnosis of anemia which has been significantly improved by this analysis. However, it is important to note that the mentioned improvements can only be achieved through highest methodological quality. Importantly, all these analyses are also applied to twins and higher order multiples. Here, for the differential diagnosis of specific complications such as TTTS, TAPS and TRAP, the application of Doppler sonography has become indispensable. To conclude, the successful application of Doppler sonography requires both exact methodology and precise pathophysiological interpretation of the data.

Stratification of pregnancy care based on risk of pre-eclampsia derived from biophysical and biochemical markers at 19-24 weeks' gestation

OBJECTIVE

We have proposed previously that all pregnant women should have assessment of risk for pre-eclampsia (PE) at 20 and 36 weeks' gestation and that the 20-week assessment should be used to define subgroups requiring additional monitoring and reassessment at 28 and 32 weeks. The objective of this study was to examine the potential improvement in screening at 19-24 weeks' gestation for PE with delivery at < 28, < 32, < 36 and ≥ 36 weeks' gestation by the addition of serum placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) to the combination of maternal demographic characteristics and medical history, uterine artery pulsatility index (UtA-PI) and mean arterial pressure (MAP).

METHODS

This was a prospective, non-intervention study in women attending for an ultrasound scan at 19-24 weeks as part of routine pregnancy care. Patient-specific risks of delivery with PE at < 36 weeks' gestation were calculated using the competing-risks model to combine the prior distribution of gestational age at delivery with PE, obtained from maternal characteristics and medical history, with multiples of the median values of UtA-PI, MAP, PlGF and sFlt-1. Different risk cut-offs were used to vary the proportion of the population stratified into each of four risk categories (very high risk, high risk, intermediate risk and low risk) with the intention of detecting about 80%, 85%, 90% and 95% of cases of delivery with PE at < 28, < 32 and < 36 weeks' gestation. The performance of screening was assessed by plotting the detection rate against the screen-positive rate and calculating the areas under these curves, and by the proportion stratified into a given group for fixed detection rates. Model-based estimates of screening performance for these various combinations of markers were also produced.

RESULTS

In the study population of 37 886 singleton pregnancies, there were 1130 (3.0%) that subsequently developed PE, including 160 (0.4%) that delivered at < 36 weeks' gestation. In both the modeled and empirical results, there was incremental improvement in the performance of screening with the addition of PlGF and sFlt-1 to the combination of maternal factors, UtA-PI and MAP. If the objective of screening was to identify about 90% of cases of PE with delivery at < 28, < 32 and < 36 weeks and the method of screening was a combination of maternal factors, UtA-PI and MAP, the respective screen-positive rates would be 3.1%, 8.5% and 19.1%. The respective values for screening by maternal factors, UtA-PI, MAP and PlGF were 0.2%, 0.7% and 10.6%, and for screening by maternal factors, UtA-PI, MAP, PlGF and sFlt-1 they were 0.1%, 0.4% and 9.5%. The empirical results were consistent with the modeled results. There was good agreement between the predicted risk and the observed incidence of PE at < 36 weeks' gestation for all three strategies of screening. Prediction of PE at ≥ 36 weeks was poor for all three screening methods, with the detection rate, at a 10% screen-positive rate, ranging from 33.2% to 38.4%.

CONCLUSIONS

The performance of screening at 19-24 weeks' gestation for PE with delivery at < 28, < 32 and < 36 weeks' gestation achieved by a combination of maternal demographic characteristics and medical history, UtA-PI and MAP is improved by the addition of serum PlGF and sFlt-1. The performance of screening for PE at ≥ 36 weeks' gestation is poor irrespective of the method of screening at 19-24 weeks. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Competing Risks Model for Prediction of Small for Gestational Age Neonates and the Role of Second Trimester Soluble Fms-like Tyrosine Kinase-1

Small for gestational age (SGA) fetuses/neonates are characterized by the increased risk for adverse outcomes that can be reduced if the condition is identified antenatally. We have recently developed a new approach in SGA prediction that considers SGA a spectrum condition that is reflected in two dimensions: gestational age at delivery and Z score in birth weight for gestational age. The new method has a better predictive ability than the traditionally used risk-scoring systems and logistic regression models. In this prospective study in 40241 singleton pregnancies, at 19–24 weeks’ gestation, we examined the potential value of the antiangiogenic soluble fms-like tyrosine kinase-1 (sFlt-1) and the ratio of sFlt-1 to the angiogenic placental growth factor (PlGF) in the prediction of SGA. We found that first, sFlt-1 did not improve the performance of screening by maternal risk factors, and second, the ratio of sFlt-1/PlGF had a worse performance than PlGF alone in the prediction of SGA. Consequently, second trimester sFlt-1 and sFlt-1/PlGF are not useful in screening for SGA.

Stratification of pregnancy care based on risk of pre-eclampsia derived from uterine artery Doppler at 19-24 weeks' gestation

OBJECTIVES

There were two objectives of this study. First, to examine the value of uterine artery pulsatility index (UtA-PI) at 19-24 weeks' gestation in the prediction of subsequent development of pre-eclampsia (PE) and to compare the performance of screening between the use of, first, fixed cut-offs of UtA-PI, second, percentile cut-offs of UtA-PI adjusted for gestational age, third, a competing-risks model combining maternal demographic characteristics and medical history with UtA-PI, and, fourth, a competing-risks model combining maternal factors with UtA-PI and mean arterial pressure (MAP). Second, to stratify pregnancy care based on the estimated risk of PE at 19-24 weeks' gestation from UtA-PI and combinations of maternal factors with UtA-PI and MAP.

METHODS

This was a prospective, non-intervention study in women attending for an ultrasound scan at 19-24 weeks as part of routine pregnancy care. Patient-specific risks of delivery with PE at < 36 weeks' gestation were calculated using the competing-risks model to combine the prior distribution of the gestational age at delivery with PE, obtained from maternal characteristics and medical history, with multiples of the median (MoM) values of UtA-PI and MAP. Different risk cut-offs were used to vary the proportion of the population stratified into each risk category (very high risk, high risk, intermediate risk and low risk) with the intention of detecting about 80%, 85%, 90% and 95% of cases of delivery with PE at < 28, < 32 and < 36 weeks' gestation. We also examined the performance of screening by maternal factors and UtA-PI MoM, fixed cut-offs of UtA-PI and percentile cut-offs of UtA-PI adjusted for gestational age. Calibration for risks for PE < 36 weeks' gestation by the combination of maternal factors, UtA-PI MoM and MAP MoM was assessed by plotting the observed incidence of PE against the predicted incidence. Additionally, we developed reference ranges of transabdominal and transvaginal measurement of UtA-PI according to gestational age.

RESULTS

In the study population of 96 678 singleton pregnancies, there were 2866 (3.0%) that subsequently developed PE, including 467 (0.5%) that delivered at < 36 weeks' gestation. If the objective of screening was to identify about 90% of cases of delivery with PE at < 28, < 32 and < 36 weeks and the method of screening was a combination of maternal factors, UtA-PI MoM and MAP MoM, the proportion of the population stratified into very high-risk, high-risk, intermediate-risk and low-risk groups would be 2.4%, 3.9%, 17.8% and 75.9%, respectively; the respective values were 6.0%, 3.0%, 21.0% and 70.0% if screening was by maternal factors and UtA-PI MoM, 5.7%, 7.5%, 49.8% and 37.0% if screening was by fixed cut-offs of UtA-PI and 6.9%, 5.2%, 49.0% and 38.9% if screening was by percentile cut-offs of UtA-PI. In the validation of the prediction model based on a combination of maternal factors and MoM values of UtA-PI and MAP, calibration plots demonstrated good agreement between the predicted risk and the observed incidence of PE.

CONCLUSIONS

All pregnant women should have screening for PE at 20 and 36 weeks' gestation. The findings at 20 weeks can be used to identify the subgroups that require additional monitoring and reassessment at 28 and 32 weeks. The performance of screening by a combination of maternal factors and MoM values of UtA-PI and MAP at 19-24 weeks for delivery with PE at < 28, < 32 and < 36 weeks' gestation is superior to that of screening by a combination of maternal factors and UtA-PI MoM, by fixed cut-offs of UtA-PI or by percentile cut-offs of UtA-PI. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Evaluation of the RCOG guideline for the prediction of neonates that are small for gestational age and comparison with the competing risks model

OBJECTIVE

To examine the predictive performance of the relevant guideline by the Royal College of Obstetricians and Gynaecologists (RCOG) for neonates that are small for gestational age (SGA), and to compare the performance of the RCOG guideline with that of our competing risks model for SGA.

DESIGN

Prospective observational study.

SETTING

Obstetric ultrasound departments in two UK maternity hospitals.

POPULATION

A total of 96 678 women with singleton pregnancies attending for routine ultrasound examination at 19-24 weeks of gestation.

METHODS

Risks for SGA for different thresholds were computed, according to the competing risks model using maternal history, second-trimester estimated fetal weight, uterine artery pulsatility index and mean arterial pressure. The detection rates by the RCOG guideline scoring system and the competing risks model for SGA were compared, at the screen positive rate (SPR) derived from the RCOG guideline.

MAIN OUTCOME MEASURES

Small for gestational age (SGA), <10th or <3rd percentile, for different gestational age thresholds.

RESULTS

At an SPR of 22.5%, as defined by the RCOG guideline, the competing risks model predicted 56, 72 and 81% of cases of neonates that are SGA, with birthweights of <10th percentile, delivered at ≥37, <37 and <32 weeks of gestation, respectively, which were significantly higher than the respective figures of 36, 44 and 45% achieved by the application of the RCOG guideline. The respective figures for neonates that were SGA with birthweights of <3rd percentile were 66, 79, 85 and 41, 45, 44%.

CONCLUSION

The detection rate for neonates that were SGA with the competing risk approach is almost double than that obtained with the RCOG guideline.

TWEETABLE ABSTRACT

The competing risks approach for the prediction of SGA performs better than the existing RCOG guideline.

Maternal cardiac function at 19-23 weeks' gestation in prediction of pre-eclampsia

OBJECTIVES

First, to examine the factors from maternal characteristics and medical history that affect maternal cardiovascular indices, and, second, to examine the potential value of maternal cardiovascular indices at 19-23 weeks' gestation, on their own and in combination with maternal factors and the established biomarkers of pre-eclampsia (PE), including uterine artery pulsatility index (UtA-PI), mean arterial pressure (MAP), serum placental growth factor (PlGF) and serum soluble fms-like tyrosine kinase-1 (sFlt-1), in the prediction of subsequent development of PE.

METHODS

This was a prospective observational study in women attending for a routine hospital visit at 19 + 1 to 23 + 3 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, assessment of maternal E/A ratio, E/e' ratio, myocardial performance index, global longitudinal systolic strain, left ventricular ejection fraction, peripheral vascular resistance, left ventricular cardiac output and left ventricular mass indexed for body surface area, and measurement of MAP, UtA-PI, serum PlGF and serum sFlt-1. The measurements of the eight maternal cardiac indices were standardized to remove the effects of maternal characteristics and elements from the medical history. The competing-risks model was used to estimate the individual patient-specific risks of delivery with PE and determine the detection rate, at a 10% false-positive rate, in screening by a combination of maternal demographic characteristics and medical history with biomarkers.

RESULTS

The study population of 2853 pregnancies contained 76 (2.7%) that developed PE. In pregnancies that subsequently developed PE, there was evidence of altered cardiac geometry, impaired myocardial function and increased peripheral vascular resistance. All maternal cardiovascular indices were affected significantly by maternal demographic characteristics and elements of medical history known to be associated with an increased risk for subsequent development of PE. After adjustment for maternal demographic characteristics and medical history, the only cardiovascular index that was affected significantly by subsequent development of PE was peripheral vascular resistance. Peripheral vascular resistance multiples of the median (MoM) was correlated with MAP MoM, which is not surprising because blood pressure is involved in the estimation of both. There were weak correlations between several cardiovascular indices and MAP MoM, but none was correlated with MoM values of UtA-PI, PlGF or sFlt-1. The performance of screening for delivery with PE at < 37 weeks' gestation or delivery with PE at any gestational age in screening by maternal demographic characteristics and medical history or combinations of maternal factors with MAP, UtA-PI, PlGF and sFlt-1 was not improved by the addition of peripheral vascular resistance.

CONCLUSION

Assessment of maternal cardiovascular function provides information on the pathophysiology of PE but is not useful in the prediction of PE. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Doppler studies of placental function

Placental-associated diseases account for most cases of adverse perinatal outcome in developing countries. Doppler evaluation has been incorporated as a predictive parameter at early pregnancy for high-risk placental disease, in the diagnosis and management of those fetuses with impaired intrauterine growth and for the evaluation of fetal wellbeing in those high-risk pregnancies. Uterine Doppler at second trimester predicts most instances of early-onset preeclampsia and intrauterine growth restriction. However, the growing evidence of an effective early propylactic strategy, has turned Uterine Doppler an essential parameter to be included in first trimester predictive algorithms. Umbilical artery Doppler helps in the identification of small-for-gestational-age fetuses at higher risk, and is one of the essential vessels in the assessment of fetal hypoxia impairment, especially in the early cases. It helps in the decision timing for ending the pregnancy improving thus perinatal outcomes. Moreover, in high-risk pregnancies, umbilical artery Doppler has demonstrated to reduce the risk of perinatal deaths and the risk of obstetric interventions. On the other hand, middle cerebral artery Doppler reflects fetal adaptation to hypoxia, and with the cerebroplacental ratio, they improve the detection of fetuses a high risk of adverse perinatal outcome, mostly of those late small fetuses, where most instances of adverse outcome occur in fetuses with normal umbilical artery. Ductus venosous Doppler waveform is a surrogate parameter of the fetal base-acid status. Its use has demonstrated to improve perinatal outcomes, mainly reducing the risk of fetal intrauterine death. Alone or in combination with computerized CTG, it helps tailoring the best moment to end the pregnancy among early cases.

First- and second-trimester uterine artery pulsatility index as a combination factor in predictive diagnosis of pregnancy-induced hypertension

OBJECTIVE

Hypertensive disorder of pregnancy is a major cause of fetal and maternal morbidity and mortality. The current approach for pregnancy-induced hypertension (PIH) screening is complex and expensive. The present prospective cohort study assesses the advantage of combining first- and second-trimester uterine artery pulsatility index (UAPI) for predictive diagnosis of PIH.

METHODS

A total of 151 prenatal cases in their first trimester were studied and followed up till delivery. The mean UAPI was calculated for the first and second trimesters during the nuchal translucency and anomaly scans. Receiver operating characteristic analysis was used to calculate the cut-off of UAPI for first-trimester, second-trimester, and both trimesters combined.

RESULTS

Twenty-seven (17.9%) pregnant women developed PIH. Mean ± SD UAPI values for first and second trimesters were 1.92 ± 0.60 and 1.23 ± 0.36, respectively. The cut-offs for abnormal UAPI were ≥2.51, ≥1.32, and ≥1.91 for first trimester, second trimester, and both trimesters combined, respectively. The sensitivity and specificity of UAPI in predictive diagnosis of PIH were 82% and 95% for first trimester, 93% and 85% for the second trimester, and 93% and 98% for both trimesters combined.

CONCLUSION

Combining UAPI of first and second trimesters improves the predictive diagnosis of PIH, which can be carried out during the nuchal translucency and anomaly scans without imparting extra cost to the patient.

Sex differences in uterine artery Doppler during gestation in pregnancies complicated by placental dysfunction

BACKGROUND

There is growing evidence of sex differences in placental vascular development. The objective of this study was to investigate the effect of fetal sex on uterine artery pulsatility index (PI) throughout gestation in a cohort of normal and complicated pregnancies.

METHODS

A prospective longitudinal study was conducted in 240 pregnant women. Pulsed wave Doppler ultrasound of the proximal uterine arteries was performed at a 4-weekly interval between 14 and 40 weeks of gestation. The patients were classified retrospectively as normal or complicated (one or more of maternal preeclampsia, preterm birth, or small for gestational age). To assess if the change in uterine artery PI during gestation differed between normal and complicated pregnancies and between fetal sexes, the uterine artery PI was modeled using a linear function of gestational age and the rate of change was estimated from the slope.

RESULTS

While the uterine artery PI did not differ over gestation between females and males for normal pregnancies, the trajectory of this index differed by fetal sex for pregnancies complicated by either preeclampsia, preterm birth, or fetal growth restriction (p < 0.0001). The male fetuses in the complicated pregnancy group had an elevated slope compared to the other groups (p < 0.0001), suggesting a more progressive deterioration in uteroplacental perfusion over gestation.

CONCLUSIONS

The uterine artery PI is widely used to assess uteroplacental function in clinical settings. The observation that this metric changes more rapidly in complicated pregnancies where the fetus was male highlights the importance of sex when interpreting hemodynamic markers of placental maturation.

Generating evidence on screening, diagnosis and management of non-communicable diseases during pregnancy; a scoping review of current gap and practice in India with a comparison of Asian context

Background

Children born to high-risk pregnancies are more likely to experience adverse health outcomes later in life. As estimated, 15% of all pregnancies are at risk of various life-threatening conditions leading to adverse maternal and foetal outcomes. Millennium Development Goal resulted in the global reduction of maternal death from 390,000 to 275000 in 1990–2015). Similarly, to keep this momentum, the current United Nations Sustainable Development Goal (SDG: 3.1) aims at reducing the global maternal mortality ratio to less than 70 per 100,000 live births by 2030, and this can be achieved by addressing high-risk pregnancy contributing to significant mortality and morbidity. In India, gestational diabetes, gestational hypertension, and gestational hypothyroidism were identified as factors contributing to the high-risk pregnancy. This review summarises the commonly used approach for screening, diagnosis, and management of these conditions in the Asian population. It draws a comparison with the current protocols and guidelines in the Indian setting.

Methods

Electronic search in PubMed and Google Scholar, reference snowballing, and review of current guidelines and protocols were done between January 2010 to October 2019. Published studies reporting Screening, diagnosis, and management of these conditions were included. Articles selected were then screened, appraised for quality, extract relevant data, and synthesised.

Results

Screening, diagnosis, and management of these three conditions vary and no single universally accepted criteria for diagnosis and management exist to date. In India, national guidelines available have not been evaluated for feasibility of implementation at the community level. There are no national guidelines for PIH diagnosis and management despite the increasing burden and contribution to maternal and perinatal morbidity and mortality. Criteria for diagnosis and management of gestational diabetes, gestational hypertension, and gestational hypothyroidism varies but overall early screening for predicting risk, as reported from majority of the articles, were effective in minimizing maternal and foetal outcome.

Conclusion

Existing National guidelines for Screening, Diagnosis, and Management of Gestational Diabetes Mellitus (2018) and Gestational Hypothyroidism (2014) need to be contextualized and modified based on the need of the local population for effective treatment. Findings from this review show that early screening for predicting risk to be an effective preventive strategy. However, reports related to a definitive diagnosis and medical management were heterogeneous.

Ophthalmic artery Doppler in combination with other biomarkers in prediction of pre-eclampsia at 19-23 weeks' gestation

OBJECTIVE

To examine the potential value of maternal ophthalmic artery Doppler at 19-23 weeks' gestation on its own and in combination with the established biomarkers of pre-eclampsia (PE), including uterine artery (UtA) pulsatility index (PI), mean arterial pressure (MAP), serum placental growth factor (PlGF) and serum soluble fms-like tyrosine kinase-1 (sFlt-1), in the prediction of subsequent development of PE.

METHODS

This was a prospective observational study of women attending for a routine hospital visit at 19 + 1 to 23 + 3 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination for fetal anatomy and growth, assessment of flow velocity waveforms from the maternal ophthalmic arteries, and measurement of MAP, UtA-PI, serum PlGF and serum sFlt-1. Waveforms were obtained from the ophthalmic arteries in sequence from the right eye, left eye and again from the right and then left eye. We recorded the average of the four measurements, two from each eye, for the following four indices: first peak of systolic velocity; second peak of systolic velocity; PI; and the ratio of the second to first peak of systolic velocity (PSV ratio). The measurements of the four indices were standardized to remove the effects of maternal characteristics and elements from the medical history. The competing-risks model was used to estimate the individual patient-specific risks of delivery with PE at < 37 and ≥ 37 weeks' gestation and to determine the area under the receiver-operating-characteristics curve (AUC) and detection rate (DR), at a 10% false-positive rate (FPR), in screening by a combination of maternal demographic characteristics and medical history with biomarkers. The modeled performance of screening for PE was also estimated.

RESULTS

The study population of 2853 pregnancies contained 76 (2.7%) that developed PE, including 18 (0.6%) that delivered with PE at < 37 weeks' gestation. The ophthalmic artery PSV ratio was significantly increased in PE pregnancies, and the PE effect depended on gestational age at delivery; the deviation from normal was greater for early than late PE. The second peak of systolic velocity was also increased in PE pregnancies, but the effect did not depend on gestational age at delivery. The other two ophthalmic artery indices of first peak of systolic velocity and PI were not significantly affected by PE. The PSV ratio improved the prediction of preterm PE provided by maternal factors alone (from 56.1% to 80.2%), maternal factors, MAP and UtA-PI (80.7% to 87.9%), maternal factors, MAP, UtA-PI and PlGF (85.5% to 90.3%) and maternal factors, MAP, UtA-PI, PlGF and sFlt-1 (84.9% to 89.8%), at a FPR of 10%. The PSV ratio also improved the prediction of term PE provided by maternal factors alone (from 33.8% to 46.0%), maternal factors, MAP and UtA-PI (46.6% to 54.2%), maternal factors, MAP, UtA-PI and PlGF (45.2% to 53.4%) and maternal factors, MAP, UtA-PI, PlGF and sFlt-1 (43.0% to 51.2%), at a FPR of 10%. The empirical results for DR at a 10% FPR were consistent with the modeled results. The second peak of systolic velocity did not improve the prediction of either preterm or term PE provided by maternal factors alone.

CONCLUSION

Ophthalmic artery PSV ratio at 19-23 weeks' gestation, both on its own and in combination with other biomarkers, is potentially useful for prediction of subsequent development of PE, especially preterm PE, but larger studies are needed to validate this finding. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Uterine vascular resistance and other maternal factors associated with the risk of developing hypertension during pregnancy

Gestational hypertension and pre-eclampsia are important causes of perinatal morbidity. The objective of the present study was to determine the increase in relative risk for developing hypertensive disorders of pregnancy based on the evaluation of pregnant women between 20 and 25 weeks of gestation, and to correlate the findings at this period with the outcome of pregnancy. We conducted a prospective cohort study, with a convenience sample of 1417 patients evaluated at this gestational age, of which 1306 were contacted at childbirth. We detected an increased relative risk of 2.69 (95%CI: 1.86 to 3.89) associated with pulsatility index of the uterine arteries, a 2.8 increase (95%CI: 1.58 to 5.03) in relative risk attributed to maternal age above 35 years, a 1.68 increase (95%CI: 1.17 to 2.40) attributed to parity greater than or equal to 3, and a 5.35 increase (95%CI: 4.18 to 6.85) attributed to chronic hypertension and obesity, with a progressive increase in relative risk according to the degree of overweight, i.e., grades 1, 2, 3, and morbid obesity (2.58, 3.06, 5.84, and 7.28, respectively).

Society for Maternal-Fetal Medicine Consult Series #52: Diagnosis and management of fetal growth restriction: (Replaces Clinical Guideline Number 3, April 2012)

Fetal growth restriction can result from a variety of maternal, fetal, and placental conditions. It occurs in up to 10% of pregnancies and is a leading cause of infant morbidity and mortality. This complex obstetrical problem has disparate published diagnostic criteria, relatively low detection rates, and limited preventative and treatment options. The purpose of this Consult is to outline an evidence-based, standardized approach for the prenatal diagnosis and management of fetal growth restriction. The recommendations of the Society for Maternal-Fetal Medicine are as follows: (1) we recommend that fetal growth restriction be defined as an ultrasonographic estimated fetal weight or abdominal circumference below the 10th percentile for gestational age (GRADE 1B); (2) we recommend the use of population-based fetal growth references (such as Hadlock) in determining fetal weight percentiles (GRADE 1B); (3) we recommend against the use of low-molecular-weight heparin for the sole indication of prevention of recurrent fetal growth restriction (GRADE 1B); (4) we recommend against the use of sildenafil or activity restriction for in utero treatment of fetal growth restriction (GRADE 1B); (5) we recommend that a detailed obstetrical ultrasound examination (current procedural terminology code 76811) be performed with early-onset fetal growth restriction (<32 weeks of gestation) (GRADE 1B); (6) we recommend that women be offered fetal diagnostic testing, including chromosomal microarray analysis, when fetal growth restriction is detected and a fetal malformation, polyhydramnios, or both are also present regardless of gestational age (GRADE 1B); (7) we recommend that pregnant women be offered prenatal diagnostic testing with chromosomal microarray analysis when unexplained isolated fetal growth restriction is diagnosed at <32 weeks of gestation (GRADE 1C); (8) we recommend against screening for toxoplasmosis, rubella, or herpes in pregnancies with fetal growth restriction in the absence of other risk factors and recommend polymerase chain reaction for cytomegalovirus in women with unexplained fetal growth restriction who elect diagnostic testing with amniocentesis (GRADE 1C); (9) we recommend that once fetal growth restriction is diagnosed, serial umbilical artery Doppler assessment should be performed to assess for deterioration (GRADE 1C); (10) with decreased end-diastolic velocity (ie, flow ratios greater than the 95th percentile) or in pregnancies with severe fetal growth restriction (estimated fetal weight less than the third percentile), we suggest weekly umbilical artery Doppler evaluation (GRADE 2C); (11) we recommend Doppler assessment up to 2-3 times per week when umbilical artery absent end-diastolic velocity is detected (GRADE 1C); (12) in the setting of reversed end-diastolic velocity, we suggest hospitalization, administration of antenatal corticosteroids, heightened surveillance with cardiotocography at least 1-2 times per day, and consideration of delivery depending on the entire clinical picture and results of additional evaluation of fetal well-being (GRADE 2C); (13) we suggest that Doppler assessment of the ductus venosus, middle cerebral artery, or uterine artery not be used for routine clinical management of early- or late-onset fetal growth restriction (GRADE 2B); (14) we suggest weekly cardiotocography testing after viability for fetal growth restriction without absent/reversed end-diastolic velocity and that the frequency be increased when fetal growth restriction is complicated by absent/reversed end-diastolic velocity or other comorbidities or risk factors (GRADE 2C); (15) we recommend delivery at 37 weeks of gestation in pregnancies with fetal growth restriction and an umbilical artery Doppler waveform with decreased diastolic flow but without absent/reversed end-diastolic velocity or with severe fetal growth restriction with estimated fetal weight less than the third percentile (GRADE 1B); (16) we recommend delivery at 33-34 weeks of gestation for pregnancies with fetal growth restriction and absent end-diastolic velocity (GRADE 1B); (17) we recommend delivery at 30-32 weeks of gestation for pregnancies with fetal growth restriction and reversed end-diastolic velocity (GRADE 1B); (18) we suggest delivery at 38-39 weeks of gestation with fetal growth restriction when the estimated fetal weight is between the 3rd and 10th percentile and the umbilical artery Doppler is normal (GRADE 2C); (19) we suggest that for pregnancies with fetal growth restriction complicated by absent/reversed end-diastolic velocity, cesarean delivery should be considered based on the entire clinical scenario (GRADE 2C); (20) we recommend the use of antenatal corticosteroids if delivery is anticipated before 33 6/7 weeks of gestation or for pregnancies between 34 0/7 and 36 6/7 weeks of gestation in women without contraindications who are at risk of preterm delivery within 7 days and who have not received a prior course of antenatal corticosteroids (GRADE 1A); and (21) we recommend intrapartum magnesium sulfate for fetal and neonatal neuroprotection for women with pregnancies that are <32 weeks of gestation (GRADE 1A).

Notching and Pulsatility Index of the Uterine Arteries and Preeclampsia in Twin Pregnancies

Increased uterine artery Doppler indices have been shown to be associated with preeclampsia and adverse pregnancy outcomes in singleton and twin pregnancies. At 20–22 weeks of gestation, we assessed the use of notching, the highest, lowest, and mean pulsatility index (PI), and the combination of notching and PI of the uterine arteries to screen for preeclampsia. This was done in a cohort of 380 twin pregnancies. The results showed that the combination of notching and the highest PI above the 95th centile of the uterine arteries gives the best screening characteristics for preeclampsia in twin pregnancies. We calculated sensitivities for preeclampsia for notching, highest PI, and the combination of notching and the highest PI of 50%, 45% and 91%, with specificities of 96%, 96% and 93%, respectively. The present findings demonstrate that notching, increased highest PI, and the combination of notching and the highest PI of the uterine arteries is associated with an increased risk of preeclampsia in twin pregnancies. We observed the highest sensitivity and specificity by using the combination of notching and the highest PI of the uterine arteries.

Role of second-trimester uterine artery Doppler indices in the prediction of adverse pregnancy outcomes in a low-risk population

OBJECTIVE

To evaluate use of second-trimester uterine artery Doppler velocimetry to predict adverse pregnancy outcomes.

METHODS

A prospective longitudinal study among low-risk nulliparous women with singleton pregnancies attending Ekiti State University Teaching Hospital, Nigeria, between July and December 2017. Uterine artery Doppler indices were measured at 22-26 gestational weeks. Resistance index (RI) of 0.58 or less and pulsatility index (PI) of 1.6 or less were considered normal. The ability of Doppler indices to predict adverse pregnancy outcomes was determined.

RESULTS

Among 120 women, 73 (60.8%) women had at least one abnormal Doppler index and 50 (41.7%) at least one adverse pregnancy outcome. For pre-eclampsia, sensitivity and specificity of RI were 40.0% and 37.3% (area under curve [AUC], 0.28), and those of PI were 20.0% and 89.1% (AUC, 0.33) respectively. For intrauterine growth restriction, sensitivity and specificity of RI were 23.1% and 34.6% (AUC, 0.22), and those of PI were 0% and 86.95% (AUC, 0.48), respectively. For low birthweight, sensitivity and specificity of RI were 60.0% and 38.9% (AUC, 0.54), and those of PI were 20.0% and 90.5% (AUC, 0.55), respectively.

CONCLUSION

Late second-trimester uterine artery Doppler velocimetry had limited ability to predict adverse pregnancy outcomes in a low-risk population.

A Pilot Randomized Trial Comparing the Effects of 80 versus 160 mg of Aspirin on Midtrimester Uterine Artery Pulsatility Index in Women with a History of Preeclampsia

OBJECTIVE

To compare the effects of 80 mg and 160 mg of aspirin, initiated in the first trimester of pregnancy, on mid-trimester uterine artery pulsatility index (UtA-PI) in women with a history of preeclampsia.

METHODS

We performed a pilot double-blind randomized controlled trial. Pregnant women with a history of preeclampsia were recruited between 10^0/7 and 13^6/7 weeks gestation and randomly assigned to take either 80 or 160 mg of aspirin daily at bedtime from randomization to 35^6/7 weeks gestation. The primary outcome was mean UtA-PI at 22-24 weeks. Secondary outcomes included the rate of fetal growth restriction and preeclampsia, stratified as term (≥37 weeks), preterm (<37 weeks), and early-onset (<34 weeks) preeclampsia.

RESULTS

A total of 107 participants were randomized, including 41 (38%) with a history of preterm preeclampsia and 16 (15%) with a history of early-onset preeclampsia. We observed no significant difference in mean UtA-PI at 22-24 weeks between the 2 groups (0.97; 95% CI 0.88-1.05 vs. 0.97; 95% CI 0.88-1.07, P = 0.9). The rates of fetal growth restriction (8% vs. 2%; P = 0.20); preeclampsia (12% vs. 15%; P = 0.78), preterm preeclampsia (4% vs. 2%; P = 0.56), and early-onset preeclampsia (0% vs. 2%; P = 0.52) were similar in both groups. No serious adverse events associated with the study treatment were reported.

CONCLUSION

We observed no significant difference in UtA-PI between the two doses of aspirin, but we observed low rates of fetal growth restriction and preterm and early-onset preeclampsia (all less than 5%). The benefits of aspirin for the prevention of preterm preeclampsia is probably not related to the improvement of deep placentation alone.

Doppler Indices and Notching Assessment of Uterine Artery Between the 19th and 22nd Week of Pregnancy in the Prediction of Pregnancy Outcome

BACKGROUND/AIM

The aim of this study was to determine the value of Doppler indices and notching assessment of uterine artery between the 19th and 22nd week of gestation in the prediction of pregnancy outcome such as delivery mode, birth weight, Apgar score, afterbirth pH, fetal presentation, preeclampsia and fetal growth restriction in singleton pregnancy.

PATIENTS AND METHODS

This is a retrospective cohort study of Doppler ultrasound of the uterine arteries at 19-22 week of gestation in 1,472 women with singleton pregnancies.

RESULTS

Patients with bilateral high resistance-index (RI) and pulsatility-index (RI) or with the presence of a notch showed a significantly higher prevalence of small for gestational age (SGA) fetuses and intrauterine growth restriction (IUGR), low Apgar Scores at the 1st and the 5th min, high c-section rate, preterm birth, breech birth, placental insufficiency and placental abruption. The presence of a notch significantly increased the prevalence of severe preeclampsia, HELLP-syndrome and oligohydramnios. Also, patients with a bilateral uterine notching had a higher c-section rate along with higher prevalence of SGA and IUGR at screening time.

CONCLUSION

Uterine artery Doppler waveform analysis as well as the assessment of the presence of a notch in the second trimester can be used as a screening method to identify women who will thereafter develop a severe adverse outcome.