Spiral, uterine artery doppler and placental ultrasound in relation to preeclampsia

Preeclampsia (PE) is a multiorgan disorder that complicates around 2-8% of pregnancies and is a major cause of perinatal and maternal morbidity and mortality. PE is a clinical syndrome characterized by hypertension secondary to systemic inflammation, endothelial dysfunction, and syncytiotrophoblast stress leading to hypertension and multiorgan dysfunction. The uterine arteries are the main blood vessels that supply blood to the uterus. They give off branches and plays an important role in maintaining blood supply during pregnancy. The arcuate artery originates from the uterine artery and runs medially through the myometrium. The arcuate arteries divide almost directly into anterior and posterior branches, from which the radial artery leads directly to the uterine cavity during their course. Near the endometrium-myometrium junction, the radial artery generates spiral arteries within the basal layer and functional endometrium. The walls of radial and spiral arteries are rich in smooth muscle, which is lost when trophoblast cells invade and become large-caliber vessels. This physiological transformation of uteroplacental spiral arteries is critical for successful placental implantation and normal placental function. In normal pregnancy, the luminal diameter of the spiral arteries is greatly increased, and the vascular smooth muscle is replaced by trophoblast cells. This process and changes in the spiral arteries are called spiral artery remodeling. In PE, this genetically and immunologically governed process is deficient and therefore there is decreased vascular capacitance and increased resistance in the uteroplacental circulation. Furthermore, this defect in uteroplacental spiral artery remodeling is not only associated with early onset PE, but also with fetal growth restriction, placental abruption, and spontaneous premature rupture of membranes. Doppler ultrasound allows non-invasive assessment of placentation, while the flow impedance decreases as the pregnancy progresses in normal pregnancies, in those destined to develop preeclampsia the impedance is increased.

Prediction of preeclampsia in asymptomatic women

Preeclampsia is a major cause of maternal and perinatal morbidity and mortality. It is important to identify women who are at high risk of developing this disorder in their first trimester of pregnancy to allow timely therapeutic intervention. The use of low-dose aspirin initiated before 16 weeks of gestation can significantly reduce the rate of preterm preeclampsia by 62 %. Effective screening recommended by the Fetal Medicine Foundation (FMF) consists of a combination of maternal risk factors, mean arterial pressure, uterine artery pulsatility index (UtA-PI) and placental growth factor (PLGF). The current model has detection rates of 90 %, 75 %, and 41 % for early, preterm, and term preeclampsia, respectively at 10 % false-positive rate. Similar risk assessment can be performed during the second trimester in all pregnant women irrespective of first trimester screening results. The use of PLGF, UtA-PI, sFlt-1 combined with other investigative tools are part of risk assessment.

Mid-trimester uterine artery Doppler for aspirin discontinuation in pregnancies at high risk for preterm pre-eclampsia: Post-hoc analysis of StopPRE trial

OBJECTIVE

To assess whether aspirin treatment can be discontinued in pregnancies with normal uterine artery pulsatility index (≤90th percentile) at 24-28 weeks.

DESIGN

Post-hoc analysis of a clinical trial.

SETTING

Nine maternity hospitals in Spain.

POPULATION OR SAMPLE

Pregnant individuals at high risk of pre-eclampsia at 11-13 weeks and normal uterine artery Doppler at 24-28 weeks.

METHODS

All participants received treatment with daily aspirin at a dose of 150 mg. Participants were randomly assigned, in a 1:1 ratio, either to continue aspirin treatment until 36 weeks (control group) or to discontinue aspirin treatment (intervention group), between September 2019 and September 2021. In this secondary analysis, women with a UtAPI >90th percentile at 24-28 weeks were excluded. The non-inferiority margin was set at a difference of 1.9% for the incidence of preterm pre-eclampsia.

MAIN OUTCOME MEASURES

Incidence of preterm pre-eclampsia.

RESULTS

Of the 1611 eligible women, 139 were excluded for UtAPI >90th percentile or if UtAPI was not available. Finally, 804 were included in this post-hoc analysis. Preterm pre-eclampsia occurred in three of 409 (0.7%) women in the aspirin discontinuation group and five of 395 (1.3%) women in the continuation group (-0.53; 95% CI -1.91 to 0.85), indicating non-inferiority of aspirin discontinuation.

CONCLUSIONS

Discontinuing aspirin treatment at 24-28 weeks in women with a UtAPI ≤90th percentile was non-inferior to continuing aspirin treatment until 36 weeks for preventing preterm pre-eclampsia.

Uterine arteries pulsatility index by Doppler ultrasound in the prediction of preeclampsia: an updated systematic review and meta-analysis

BACKGROUND

Preeclampsia is a common pregnancy complication with serious potential risks for maternal and neonatal health. Early prediction of preeclampsia is crucial for timely prevention, surveillance, and treatment to improve maternal and neonatal outcomes. This systematic review aimed to summarize the available evidence on the prediction of preeclampsia based on Doppler ultrasound of uterine arteries at different gestational ages.

METHODS

A systematic literature search and meta-analysis were conducted to evaluate the sensitivity and specificity of the pulsatility index of Doppler ultrasound of uterine arteries for predicting preeclampsia. The timing of ultrasound scans within and beyond 20 weeks of gestational age was compared to assess its effect on the sensitivity and specificity of the pulsatility index.

RESULTS

This meta-analysis included 27 studies and 81,673 subjects (3309 preeclampsia patients and 78,364 controls). The pulsatility index had moderate sensitivity (0.586) and high specificity for predicting preeclampsia (0.879) (summary point: sensitivity 0.59; 1-specificity 0.12). Subgroup analysis revealed that ultrasound scans performed within 20 weeks of gestational age did not significantly affect the sensitivity and specificity for predicting preeclampsia. The summary receiver operator characteristic curve showed the pulsatility index's optimal range of sensitivity and specificity.

CONCLUSIONS

The uterine arteries pulsatility index measured by Doppler ultrasound is useful and effective for predicting preeclampsia and should be implemented in the clinical practice. The timing of ultrasound scans at different gestational age ranges does not significantly affect the sensitivity and specificity.

Re: Reference ranges of uterine artery pulsatility index from first to third trimester based on serial Doppler measurements: longitudinal cohort study

Linked article: This Correspondence comments on Cavoretto et al. Click here to view the article.

Prediction by uterine artery Doppler screening of small-for-gestational-age neonates at 19-24 weeks' gestation

OBJECTIVE

Small-for-gestational-age (SGA) neonates are at increased risk of perinatal mortality and morbidity. We aimed to investigate the performance of uterine artery pulsatility index (UtA-PI) at 19-24 weeks' gestation to predict the delivery of a SGA neonate in a Chinese population.

METHODS

This was a retrospective cohort study using data obtained between January 2010 and June 2018. Doppler ultrasonography was performed at 19-24 weeks' gestation. SGA was defined as birth weight below the 10th centile according to the INTERGROWTH-21st fetal growth standards. The performance of UtA-PI to predict the delivery of a SGA neonate was assessed using receiver-operating-characteristics (ROC)-curve analysis.

RESULTS

We included 6964 singleton pregnancies, of which 748 (11%) delivered a SGA neonate, including 115 (15%) women with preterm delivery. Increased UtA-PI was associated with an elevated risk of SGA, both in neonates delivered at or after 37 weeks' gestation (term SGA) and those delivered before 37 weeks (preterm SGA). The areas under the ROC curve (AUCs) for UtA-PI were 64.4% (95% CI, 61.5-67.3%) and 75.8% (95% CI, 69.3-82.3%) for term and preterm SGA, respectively. The performance of combined screening by maternal demographic/clinical characteristics and estimated fetal weight in the detection of term and preterm SGA was improved significantly by the addition of UtA-PI, although the increase in AUC was modest (2.4% for term SGA and 4.9% for preterm SGA).

CONCLUSIONS

This is the first Chinese study to evaluate the role of UtA-PI at 19-24 weeks' gestation in the prediction of the delivery of a neonate with SGA. The addition of UtA-PI to traditional risk factors improved the screening performance for SGA, and this improvement was greater in predicting preterm SGA compared with term SGA. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Association between abnormal uterine artery pulsatility index and the risk of fetal congenital heart defects: a hospital-based cohort study

To explore the associations between high uterine artery pulsatility index (UtA-PI) values and congenital heart disease (CHD) risk and whether they differed between singleton and multiple pregnancies. This hospital-based cohort study involving 52,047 pregnant women who underwent prenatal examinations from 2012 to 2016. Infants born to the included pregnant women were followed until 42 days after birth to identify those with CHDs. Generalized estimating equations were used to estimate the associations of high right UtA-PI (> 95th percentile) values with maternal preeclampsia and fetal CHDs. Logistic regression analyses were conducted using path analysis models to quantify the effect of high right UtA-PI values on fetal CHD risk. A total of 42,552 women and 43,470 infants (147 with CHDs) were included. Preeclampsia risk was associated with a high right UtA-PI in singleton-pregnant women (adjusted PR, 3.01; 95% CI 2.57-3.52). CHD risk was marginally associated with a high right UtA-PI in singleton-pregnant women (adjusted PR, 2.26, 95% CI 1.03-4.95). Considering only two factors, 96.0% of the fetal CHD risk was mediated by preeclampsia in singleton-pregnant women, while 93.8% of the risk was related to a high right UtA-PI in multiple-pregnant women. A high right UtA-PI was marginally associated with an increased fetal CHD risk in singleton-pregnant women and might play an important role in multiple-pregnant women. Further studies are warranted to confirm these findings given the high loss to follow-up rate.

Clinical effectiveness of routine first-trimester combined screening for pre-eclampsia in Spain with the addition of placental growth factor

INTRODUCTION

Pre-eclampsia affects 2%-8% of pregnancies and is one of the leading causes of maternal and perinatal morbidity and mortality. First-trimester screening using an algorithm that combines maternal characteristics, mean arterial blood pressure, uterine artery pulsatility index and biomarkers (pregnancy-associated plasma protein-A and placental growth factor) is the method that achieves a greater diagnostic accuracy. It has been shown that daily salicylic acid administration before 16 weeks in women at a high risk for pre-eclampsia can reduce the incidence of preterm pre-eclampsia. However, no previous studies have evaluated the impact of routine first-trimester combined screening for pre-eclampsia with placental growth factor after being implemented in the clinical practice.

MATERIAL AND METHODS

This was a multicenter cohort study conducted in eight different maternities across Spain. Participants in the reference group were prospectively recruited between October 2015 and September 2017. Participants in the study group were retrospectively recruited between March 2019 and May 2021. Pre-eclampsia risk was calculated between 11+0 and 13+6  weeks using the Gaussian algorithm combining maternal characteristics, mean arterial pressure, uterine arteries pulsatility index, pregnancy-associated plasma protein-A and placental growth factor. Patients with a risk greater than 1/170 were prescribed daily salicylic acid 150 mg until 36 weeks. Patients in the reference group did not receive salicylic acid during gestation.

RESULTS

A significant reduction was observed in preterm pre-eclampsia (OR 0.47; 95% CI: 0.30-0.73), early-onset (<34 weeks) pre-eclampsia (OR 0.35; 95% CI: 0.16-0.77), preterm small for gestational age newborn (OR 0.57; 95% CI: 0.40-0.82), spontaneous preterm birth (OR 0.72; 95% CI: 0.57-0.90), and admission to intensive care unit (OR 0.55; 95% CI: 0.37-0.81). A greater treatment adherence resulted in a significant reduction in adverse outcomes.

CONCLUSIONS

Routine first-trimester screening for pre-eclampsia with placental growth factor leads to a reduction in preterm pre-eclampsia and other pregnancy complications. Aspirin treatment compliance has a great impact on the effectiveness of this screening program.

Is a sFlt-1/PlGF cutoff of 38 suitable to predict adverse outcomes in pregnancies with abnormal uterine artery Doppler velocimetry in the second trimester?

OBJECTIVE

To determine the optimal cutoff value for the soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) ratio to predict maternal and fetal adverse events in pregnancies with uterine artery Doppler scans results above the 95th percentile in the late second trimester.

STUDY DESIGN

Retrospective, observational cohort study on 116 asyntomatic patients with abnormal uterine artery Doppler scans at gestational week 25. The sFlt-1/PlGF ratio was determined within the weeks 25 to 29 of gestation and ROC curve analysis performed. The diagnostic validity of different cutoff values to predict severe maternal and fetal complications, i.e. preeclampsia, fetal growth restriction, placental abruption, and fetal death, was analyzed.

MAIN OUTCOME MEASURES

An ideal cutoff for sFlt-1/PlGF ratios in pregnancies with abnormal uterine artery Doppler in the second trimester.

RESULTS

Applying a cutoff point of 38, the area under the ROC curve was 0.89, generally considered low risk in fetal and maternal complication prediction. The sensitivity was 32.1%, the specificity 98.4%, the positive predictive value (PPV) 94.4%, and the negative predictive value (NPV) 63.3%. A cutoff value of 10, leading to the highest Youden index, performed best at detecting overall complications, increasing sensitivity to 69.8% and the NPV to 76.8%. at the cost of a reduced specificity and PPV.

CONCLUSIONS

In pregnancies with abnormal uterine artery Doppler in the second trimester, an sFlt-1/PlGF cutoff value greater than equal to 38 improves its predictive power for adverse events.

Longitudinal assessment of spiral and uterine arteries in normal pregnancy using novel ultrasound tool

OBJECTIVES

To use superb microvascular imaging (SMI) to evaluate longitudinally spiral artery (SA) and uterine artery (UtA) vascular adaptation in normal human pregnancy, and to develop reference ranges for use at various gestational ages throughout pregnancy.

METHODS

The data for this study were obtained from the National Institutes of Health (NIH)-funded Human Placenta Project. Women aged 18-35 years, with a body mass index < 30 kg/m2 , without comorbidities, with a singleton gestation conceived spontaneously, and gestational age at or less than 13 + 6 weeks were eligible for inclusion. The current analysis was restricted to uncomplicated pregnancies carried to term. Exclusion criteria included maternal or neonatal complications, fetal or umbilical cord anomalies, abnormal placental implantation or delivery < 37 weeks. Women who fulfilled the inclusion criteria formed the reference population of the Human Placenta Project study. Each participant underwent eight ultrasound examinations during pregnancy. The pulsatility index (PI) of both the left and right UtA were obtained twice for each artery and the presence or absence of a notch was noted. Using SMI technology, the total number of SA imaged was recorded in a sagittal placental section at the level of cord insertion. The PI and peak systolic velocity (PSV) were also measured in a total of six SA, including two in the central portion of the placenta, two peripherally towards the uterine fundal portion, and two peripherally towards the lower uterine segment.

RESULTS

A total of 90 women fulfilled the study criteria. Maternal UtA-PI decreased throughout the first half of pregnancy from a mean ± SD of 1.39 ± 0.50 at 12-13 weeks' gestation to 0.88 ± 0.24 at 20-21 weeks' gestation. The mean number of SA visualized in a sagittal plane of the placenta increased from 8.83 ± 2.37 in the first trimester to 16.99 ± 3.31 in the late-third trimester. The mean SA-PI was 0.57 ± 0.12 in the first trimester and decreased progressively during the second trimester, reaching a nadir of 0.40 ± 0.10 at 24-25 weeks, and remaining constant until the end of pregnancy. SA-PSV was highest in early pregnancy with a mean of 57.16 ± 14.84 cm/s at 12-13 weeks' gestation, declined to a mean of 49.38 ± 17.88 cm/s at 20-21 weeks' gestation and continued to trend downward for the remainder of pregnancy, reaching a nadir of 34.50 ± 15.08 cm/s at 36-37 weeks' gestation. A statistically significant correlation was noted between SA-PI and UtA-PI (r = 0.5633; P < 0.001). Multilevel regression models with natural cubic splines were used to create reference ranges of SA-PSV and SA-PI for given gestational ages.

CONCLUSION

From early gestation, we have demonstrated the ability to image and quantify SA blood flow in normal pregnancy, and have developed reference ranges for use at various gestational ages throughout pregnancy. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

First trimester SHARP1 and second-trimester uterine artery Doppler to predict preeclampsia

OBJECTIVES

The objective of this study was to identify the predictive value of the first-trimester serum SHARP1 level and the second-trimester uterine artery Doppler in singleton pregnancy for the prediction of preeclampsia.

METHODS

A prospective study including singleton pregnancy presenting at an antenatal clinic, King Chulalongkorn Memorial Hospital, Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University from 2019-March 2020 was conducted. Serum SHARP1 was collected at the gestational age (GA) of 11-13+6 weeks, and transabdominal uterine artery Doppler ultrasound was performed at GA of 18-24 weeks. Serum SHARP1 level and uterine artery pulsatility index (PI) were combined to calculate the predictive value for preeclampsia detection.

RESULTS

288 pregnant women were enrolled in the first trimester, but only 249 participants completed the study. Thirteen patients had preeclampsia (5.2%), which three cases (1.2%) had early-onset preeclampsia. The median serum SHARP1 level in the first trimester of pregnant women with preeclampsia was lower than the normal pregnancy group (1392 pg/ml vs. 1941 pg/ml, p = 0.046). The second-trimester uterine artery PI and prevalence of early diastolic notching were higher in the preeclampsia group than in the normal pregnancy group (p = 0.029 and p = 0.001, respectively). When the first-trimester serum SHARP1 level is combined with the second-trimester uterine artery PI, the sensitivity, specificity, PPV, and NPV for preeclampsia prediction were 84.6%, 47.5%, 8.2%, and 98.3%, respectively.

CONCLUSIONS

This study demonstrated that serum SHARP1 level in the first trimester combined with the uterine artery PI in the second trimester had good sensitivity to predict preeclampsia.

The predictive value of uterine artery Doppler in the success rate of pregnancy from the first frozen embryo transfer during the implantation window

BACKGROUND

Worldwide, frozen embryo transfer (FET) has become a new strategy for the treatment of infertility. The success of FET is closely related to endometrial receptivity. Does uterine artery Doppler during the implantation window predict pregnancy outcome from the first FET?

METHODS

A total of 115 retrospectively collected cycles were included in the study, with 64 cycles of clinical pregnancy and 51 cycles of nonclinical pregnancy; There were 99 nonabsent end-diastolic flow (NAEDF) cycles and 16 absent end-diastolic flow (AEDF) cycles. The differences in uterine artery Doppler findings between different pregnancy outcomes were investigated. The clinical pregnancy rate and spontaneous abortion rate in the NAEDF and AEDF groups were compared. The predictive value of uterine artery Doppler during the implantation window in the success rate of pregnancy from the first FET was also investigated.

RESULTS

Between the clinical pregnancy group and the nonclinical pregnancy group, there were no significant differences in the mean resistance index (mRI) (Z = -1.065, p = 0.287), mean pulsatility index (mPI) (Z = -0.340, p = 0.734), and mean peak systolic/end-diastolic velocity(mS/D) (Z = -0.953, p = 0.341); there were significant differences in the mean peak systolic velocity (mPSV) (Z = -1.982, p = 0.048) and mean end-diastolic velocity (mEDV) (Z = -2.767, p = 0.006). Between the NAEDF and AEDF groups, there was no significant difference in the clinical pregnancy rate (χ2 = 0.003, p = 0.959), and there was a significant difference in the spontaneous abortion rate (χ2 = 3.465, p = 0.019). Compared with uterine artery Doppler alone, its combination with artificial abortion history, waist-to-hip ratio, LH (Luteinizing hormone) of P (Progesterone) administration day, mPSV and mEDV had a higher predictive value regarding clinical pregnancy from the first FET [ROC-AUC 0.782, 95% CI (0.680-0.883) vs. 0.692, 95% CI (0.587-0.797)].

CONCLUSIONS

Uterine artery Doppler, particularly mPSV and mEDV during the implantation window, was useful for predicting clinical pregnancy, and AEDF was related to spontaneous abortion in the first trimester. Uterine artery Doppler combined with artificial abortion history, waist-to-hip ratio, LH of P administration day, mPSV and mEDV have a higher predictive value than uterine artery Doppler alone regarding the pregnancy from the first FET.

Ovarian and uterine arteries blood flow velocities waveform, hormones and nitric oxide in relation to ovulation in cows superstimulated with equine chorionic gonadotropin and luteolysis induction 10 and 17 days after ovulation

To investigate the ovarian responses, ovarian and uterine hemodynamics, circulating ovarian hormones, and nitric oxide (NO) with their relations in superstimulated cows. Eight Holstein Friesian dry cows previously synchronized with CIDR underwent rectal Doppler ultrasound scanning and blood sampling after administrating eCG (1500 I.U) on day 10 of the second ovulation (day -5). Cows were treated with 12.5 mg prostaglandin F2α (PGF2α) on days 10 and 17 after ovulation. Estradiol, progesterone, and NO were measured. Results showed that from ≥ 13 follicles, five follicles ovulated from both ovaries. The ovulated follicles increased antrum colored area and colored area % till day -1. The developed corpora lutea (CLs) attained similar diameter, area, colored area, and colored area % from day 2 till day 15. The peak point of velocity (PSV) of uterine arteries decreased while that of ovarian arteries increased from day -4 to day 0. Both ovarian arteries diameter, resistance index (RI), PSV, end velocity (EDV) and systolic/diastolic ratio (S/D) positively correlated (P < 0.0001), but their pulsatility index (PI) negatively correlated (P < 0.0001). The uterine arteries PI, RI, PSV, EDV, time average velocity (TAMV) and S/D negatively correlated (P < 0.0001) but their diameters positively correlated. Estradiol increased but progesterone decreased from day -5 till day 0. After ovulation, P4 reached maximum values on day 9 and started to decrease till day 19.NO showed one peak on day -3 and another one from day 3 to day 9. Conclusions: Blood flow of ovarian arteries is different from uterine arteries and depended on pre- or post-ovulation.

Sonographic evaluation of maternal uterine artery from 11 - 30 weeks 6 days of gestational age in a Nigerian population: A predictive index for pre-eclampsia and intrauterine growth restriction

INTRODUCTION

Uterine artery (UtA) Doppler sonography is a potential screening tool for pregnancy complications in placental insufficiency. Evaluation of the maternal and fetal vessels in pregnancy ensures accurate identification and prediction of pregnancy complications, such as preeclampsia (PE) and intrauterine growth restrictions (IUGR). The study aims to establish local reference values for UtA in a Nigerian population.

METHODS

This prospective longitudinal study was conducted among 230 pregnant women. All participants had their left (Lt) and right (RT) UtAs evaluated with a Doppler ultrasound from 11 to 30 weeks 6 days of gestational age. Peak systolic velocity (PSV), End diastolic Velocity (EDV), Systolic/Diastolic ratio (S/D), Pulsatility Index (PI), and Resistivity Index (RI) were measured and documented.

RESULTS

The mean values of UtA at 11-30 weeks 6 days of GA ranged as follows: 0.79-0.53 (RI), 1.83-0.79 (PI), 5.16-2.23 (S/D), 96.37-98.00 (PSV) & 26.07-44.14 (EDV). While the mean values of the Rt. & Lt. UtA 's ranged as follows: 0.79-0.50 (RI. Rt), 0.78-0.56 (RI. Lt), 2.05-0.80 (PI. Rt), 1.61-0.78 (PI. Lt), 6.03-2.13 (S/D. Rt), 4.29-2.33 (S/D. Lt), 89.79-99.23 (PSV. Rt), 102.76-96.71 (PSV. Lt) & 23.31-45.25 (EDV. Rt), 28.83-43.02 (EDV. Lt) respectively.

CONCLUSION

UtA Doppler reference range was established in the study population. These reference ranges will be of clinical value in daily obstetric practice.

IMPLICATION FOR PRACTICE

Obstetricians and sonographers will apply these values for early prediction of pregnancies at risk of complications in the locality.

Third-trimester uterine artery Doppler for prediction of adverse outcome in late small-and adequate for-gestational-age fetuses

Fetal growth restriction includes all those fetuses that do not reach their own growth potential due to placental insufficiency and therefore at higher risk of adverse perinatal outcomes. Identification and follow-up of these fetuses is essential to decrease this additional risk. Although estimated fetal weight under the 3rd centile and pathological cerebroplacental ratio are the most accepted predictive criteria, some evidence suggests that abnormal uterine artery Doppler may be a useful prognostic parameter in late-onset growth restriction fetuses at the moment of diagnosis. However, its prediction capacity as a standalone parameter is limited. In that context, integrated models of biometric and hemodynamic ultrasound parameters including uterine Doppler have been proposed as an effective approach to stratify the risk and improve perinatal outcomes. Moreover, an association of abnormal uterine artery Doppler and histological findings of placental underperfusion due to vascular obstruction has been described. Finally, it has also been suggested that the evaluation of uterine artery Doppler at third trimester in appropriate-for-gestational-age fetuses could identify cases of subclinical placental insufficiency, but further evidence is needed to define such predictive strategies.

Performance of first-trimester combined screening for preterm pre-eclampsia: findings from cohort of 10 110 pregnancies in Spain

OBJECTIVE

To evaluate the diagnostic accuracy of the Fetal Medicine Foundation (FMF) competing-risks model, incorporating maternal characteristics, mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and placental growth factor (PlGF) (the 'triple test'), for the prediction at 11-13 weeks' gestation of preterm pre-eclampsia (PE) in a Spanish population.

METHODS

This was a prospective cohort study performed in eight fetal medicine units in five different regions of Spain between September 2017 and December 2019. All pregnant women with a singleton pregnancy and a non-malformed live fetus attending a routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation were invited to participate. Maternal demographic characteristics and medical history were recorded and MAP, UtA-PI, serum PlGF and pregnancy-associated plasma protein-A (PAPP-A) were measured following standardized protocols. Treatment with aspirin during pregnancy was also recorded. Raw values of biomarkers were converted into multiples of the median (MoM), and audits were performed periodically to provide regular feedback to operators and laboratories. Patient-specific risks for term and preterm PE were calculated according to the FMF competing-risks model, blinded to pregnancy outcome. The performance of screening for PE, taking into account aspirin use, was assessed by calculating the area under the receiver-operating-characteristics curve (AUC) and detection rate (DR) at a 10% fixed screen-positive rate (SPR). Risk calibration of the model was assessed.

RESULTS

The study population comprised 10 110 singleton pregnancies, including 72 (0.7%) that developed preterm PE. In the preterm PE group, compared to those without PE, median MAP MoM and UtA-PI MoM were significantly higher, and median serum PlGF MoM and PAPP-A MoM were significantly lower. In women with PE, the deviation from normal in all biomarkers was inversely related to gestational age at delivery. Screening for preterm PE by a combination of maternal characteristics and medical history with MAP, UtA-PI and PlGF had a DR, at 10% SPR, of 72.7% (95% CI, 62.9-82.6%). An alternative strategy of replacing PlGF with PAPP-A in the triple test was associated with poorer screening performance for preterm PE, giving a DR of 66.5% (95% CI, 55.8-77.2%). The calibration plot showed good agreement between predicted risk and observed incidence of preterm PE, with a slope of 0.983 (95% CI, 0.846-1.120) and an intercept of 0.154 (95% CI, -0.091 to 0.397).

CONCLUSIONS

The FMF model is effective in predicting preterm PE in the Spanish population at 11-13 weeks' gestation. This method of screening is feasible to implement in routine clinical practice, but it should be accompanied by a robust audit and monitoring system, in order to maintain high-quality screening. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Screening for pre-eclampsia by maternal serum glycosylated fibronectin at 11-13 weeks' gestation

OBJECTIVE

To examine the performance of screening for preterm and term pre-eclampsia (PE) at 11-13 weeks' gestation by maternal factors and combinations of maternal serum glycosylated fibronectin (GlyFn), mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and serum placental growth factor (PlGF).

METHODS

This was a case-control study in which maternal serum GlyFn was measured using a point-of-care device in stored samples from a non-intervention screening study of singleton pregnancies at 11 + 0 to 13 + 6 weeks' gestation. In the same samples, PlGF was measured by time-resolved fluorometry. We used samples from women who delivered with PE at < 37 weeks' gestation (n = 100), PE at ≥ 37 weeks (n = 100), gestational hypertension (GH) at < 37 weeks (n = 100), GH at ≥ 37 weeks (n = 100) and 1000 normotensive controls with no pregnancy complications. In all cases, MAP and UtA-PI had been measured during the routine 11-13-week visit. Levels of GlyFn were transformed to multiples of the expected median (MoM) values after adjusting for maternal demographic characteristics and elements of medical history. Similarly, the measured values of MAP, UtA-PI and PlGF were converted to MoMs. The competing-risks model was used to combine the prior distribution of gestational age at delivery with PE, obtained from maternal characteristics, with various combinations of biomarker MoM values to derive the patient-specific risks of delivery with PE or GH at < 37 and ≥ 37 weeks' gestation. Screening performance was estimated by examining the area under the receiver-operating-characteristics curve (AUC) and detection rate (DR) at 10% fixed false-positive rate (FPR).

RESULTS

The maternal characteristics and elements of medical history with a significant effect on the measurement of GlyFn were maternal age, weight, height, race, smoking status and history of PE. In pregnancies that developed PE, GlyFn MoM was increased and the deviation from normal decreased with increasing gestational age at delivery. The DR and AUC of screening for delivery with PE at < 37 weeks' gestation by maternal factors alone were 50% and 0.834, respectively, and these increased to 80% and 0.949, respectively, when maternal risk factors were combined with MAP, UtA-PI and PlGF (triple test). The performance of the triple test was similar to that of screening by a combination of maternal factors, MAP, UtA-PI and GlyFn (DR, 79%; AUC, 0.946) and that of screening by a combination of maternal factors, MAP, PlGF and GlyFn (DR, 81%; AUC, 0.932). The performance of screening for delivery with PE at ≥ 37 weeks' gestation was poor; the DR for screening by maternal factors alone was 35% and increased to only 39% with use of the triple test. Similar results were obtained when GlyFn replaced PlGF or UtA-PI in the triple test. The DR of screening for GH with delivery at < 37 and ≥ 37 weeks' gestation by maternal factors alone was 34% and 25%, respectively, and increased to 54% and 31%, respectively, with use of the triple test. Similar results were obtained when GlyFn replaced PlGF or UtA-PI in the triple test.

CONCLUSIONS

GlyFn is a potentially useful biomarker in first-trimester screening for preterm PE, but the findings of this case-control study need to be validated by prospective screening studies. The performance of screening for term PE or GH at 11 + 0 to 13 + 6 weeks' gestation by any combination of biomarkers is poor. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Association between transabdominal uterine artery Doppler and small-for-gestational-age: a systematic review and meta-analysis

BACKGROUND

The association between uterine artery Doppler (UtA) measurements and small for gestational age (SGA) has not been quantitatively analyzed throughout the whole pregnancy. This systematic review and meta-analysis aims to comprehensively explore the association between UtA measurements and SGA in the first, second, and third trimesters.

METHODS

Studies were searched from Pubmed, Embase, Cochrane Library, and Web of Science. Weighted mean difference (WMD), odds ratio (OR), and relative risk (RR) with 95% confidence interval (CI) were used as the effect size. Heterogeneity of all effect sizes was tested and quantified using I2 statistics. Sensitivity analysis was conducted for all outcomes, and publication bias was evaluated using Begg's test.

RESULTS

A total of 41 studies were finally included in our meta-analysis. In the first trimester, mean PI was significantly higher in the SGA group than the non-SGA group (WMD: 0.31, 95%CI: 0.19-0.44). In the second trimester, odds of notch presence (OR: 2.54, 95%CI: 2.10-3.08), mean PI (WMD: 0.21, 95%CI: 0.12-0.30), and mean RI (WMD: 0.05, 95%CI: 0.05-0.06) were higher in the SGA group. Also, abnormal UtA measurements were associated with the increased odds of SGA (all P < 0.05). In the third trimester, PI z-score (WMD: 0.62, 95%CI: 0.33-0.91) and PI MoM (WMD: 0.08, 95%CI: 0.06-0.09) showed a significant increase in the SGA group. The odds of SGA were higher in the women with mean PI > 95% (OR: 6.03, 95%CI: 3.24-11.24).

CONCLUSIONS

Abnormal UtA measurements were associated with high odds of SGA, suggesting that UtA might be an adjunctive screening method for SGA in the whole pregnancy.

External validation of Fetal Medicine Foundation competing-risks model for midgestation prediction of small-for-gestational-age neonates in Spanish population

OBJECTIVE

To examine the external validity of the new Fetal Medicine Foundation (FMF) competing-risks model for prediction in midgestation of small-for-gestational-age (SGA) neonates.

METHODS

This was a single-center prospective cohort study of 25 484 women with a singleton pregnancy undergoing routine ultrasound examination at 19 + 0 to 23 + 6 weeks' gestation. The FMF competing-risks model for the prediction of SGA combining maternal factors and midgestation estimated fetal weight by ultrasound scan (EFW) and uterine artery pulsatility index (UtA-PI) was used to calculate risks for different cut-offs of birth-weight percentile and gestational age at delivery. The predictive performance was evaluated in terms of discrimination and calibration.

RESULTS

The validation cohort was significantly different in composition compared with the FMF cohort in which the model was developed. In the validation cohort, at a 10% false-positive rate (FPR), maternal factors, EFW and UtA-PI yielded detection rates of 69.6%, 38.7% and 31.7% for SGA < 10th percentile with delivery at < 32, < 37 and ≥ 37 weeks' gestation, respectively. The respective values for SGA < 3rd percentile were 75.7%, 48.2% and 38.1%. Detection rates in the validation cohort were similar to those reported in the FMF study for SGA with delivery at < 32 weeks but lower for SGA with delivery at < 37 and ≥ 37 weeks. Predictive performance in the validation cohort was similar to that reported in a subgroup of the FMF cohort consisting of nulliparous and Caucasian women. Detection rates in the validation cohort at a 15% FPR were 77.4%, 50.0% and 41.5% for SGA < 10th percentile with delivery at < 32, < 37 and ≥ 37 weeks, respectively, which were similar to the respective values reported in the FMF study at a 10% FPR. The model had satisfactory calibration.

CONCLUSION

The new competing-risks model for midgestation prediction of SGA developed by the FMF performs well in a large independent Spanish population. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Uterine artery Doppler in early labor and perinatal outcome in low-risk term pregnancy: prospective multicenter study

OBJECTIVE

The prediction of adverse perinatal outcomes in low-risk pregnancies is poor, mainly owing to the lack of reliable biomarkers. Uterine artery (UtA) Doppler is closely associated with placental function and may facilitate the peripartum detection of subclinical placental insufficiency. The objective of this study was to evaluate the association of mean UtA pulsatility index (PI) measured in early labor with obstetric intervention for suspected intrapartum fetal compromise and adverse perinatal outcome in uncomplicated singleton term pregnancies.

METHODS

This was a prospective multicenter observational study conducted across four tertiary maternity units. Low-risk term pregnancies with spontaneous onset of labor were included. The mean UtA-PI was recorded between uterine contractions in women admitted for early labor and converted into multiples of the median (MoM). The primary outcome of the study was the occurrence of obstetric intervention, i.e. Cesarean section or instrumental delivery, for suspected intrapartum fetal compromise. Secondary outcomes were the occurrence of adverse perinatal outcomes, including 5-min Apgar score < 7, low cord arterial pH, raised cord arterial base excess, admission to the neonatal intensive care unit (NICU) and postnatal diagnosis of small-for-gestational-age fetus. Composite adverse perinatal outcome was defined as the occurrence of at least one of the following: acidemia in the umbilical artery, defined as pH < 7.10 and/or base excess > 12 mmol/L, 5-min Apgar score < 7 or admission to the NICU.

RESULTS

Overall, 804 women were included, of whom 40 (5.0%) had abnormal mean UtA-PI MoM. Women who had an obstetric intervention for suspected intrapartum fetal compromise were more frequently nulliparous (72.2% vs 53.6%; P = 0.008), had a higher frequency of increased mean UtA-PI MoM (13.0% vs 4.4%; P = 0.005) and had a longer duration of labor (456 ± 221 vs 371 ± 192 min; P = 0.01). On logistic regression analysis, only increased mean UtA-PI MoM (adjusted odds ratio (aOR), 3.48 (95% CI, 1.43-8.47); P = 0.006) and parity (aOR, 0.45 (95% CI, 0.24-0.86); P = 0.015) were independently associated with obstetric intervention for suspected intrapartum fetal compromise. Increased mean UtA-PI MoM was associated with a sensitivity of 0.13 (95% CI, 0.05-0.25), specificity of 0.96 (95% CI, 0.94-0.97), positive predictive value of 0.18 (95% CI, 0.07-0.33), negative predictive value of 0.94 (95% CI, 0.92-0.95), positive likelihood ratio of 2.95 (95% CI, 1.37-6.35) and negative likelihood ratio of 0.91 (95% CI, 0.82-1.01) for obstetric intervention for suspected intrapartum fetal compromise. Pregnancies with increased mean UtA-PI MoM also showed a higher incidence of birth weight < 10th percentile (20.0% vs 6.7%; P = 0.002), NICU admission (7.5% vs 1.2%; P = 0.001) and composite adverse perinatal outcome (15.0% vs 5.1%; P = 0.008).

CONCLUSION

Our study, conducted in a cohort of low-risk term pregnancies enrolled in early spontaneous labor, showed an independent association between increased mean UtA-PI and obstetric intervention for suspected intrapartum fetal compromise, albeit with moderate capacity to rule in, and poor capacity to rule out, this condition. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of 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.

Confined placental mosaicism: placental size and function evaluated on magnetic resonance imaging

OBJECTIVES

Evidence regarding placental function in pregnancies complicated by confined placental mosaicism (CPM) is conflicting. We aimed to compare placental function between CPM and non-CPM pregnancies prenatally and at birth. A secondary objective was to evaluate the relationship between placental function and chromosomal subtype of CPM.

METHODS

This was a retrospective study of pregnancies with CPM and control pregnancies delivered at a tertiary hospital in Denmark between 2014 and 2017. Placental volume and placental transverse relaxation time (T2*) were estimated on magnetic resonance imaging (MRI), fetal weight and uterine artery pulsatility index (UtA-PI) were estimated on ultrasound and fetoplacental ratio was assessed on MRI and at birth. These estimates of placental function were adjusted for gestational age and compared between groups using the Wilcoxon rank-sum test. Within the group of CPM pregnancies, measures of placental function were compared between those at high risk (chromosome numbers 2, 3, 7, 13 and 16) and those at low risk (chromosome numbers 5, 18 and 45X).

RESULTS

A total of 90 pregnancies were included, of which 12 had CPM and 78 were controls. MRI and ultrasound examinations were performed at a median gestational age of 32.6 weeks (interquartile range, 24.7-35.3 weeks). On MRI assessment, CPM placentae were characterized by a lower placental T2* Z-score (P = 0.004), a lower fetoplacental ratio (P = 0.03) and a higher UtA-PI Z-score (P = 0.03), compared with non-CPM placentae. At birth, the fetoplacental ratio was significantly lower (P = 0.02) and placental weight Z-score was higher (P = 0.01) in CPM pregnancies compared with non-CPM pregnancies. High-risk CPM pregnancies showed a reduced placental T2* Z-score (P = 0.003), lower birth-weight Z-score (P = 0.041), earlier gestational age at delivery (P = 0.019) and higher UtA-PI Z-score (P = 0.028) compared with low-risk CPM pregnancies. Low-risk CPM pregnancies did not differ in any of these parameters from non-CPM pregnancies.

CONCLUSIONS

CPM pregnancies are characterized by an enlarged and dysfunctional placenta. Placental function was highly related to the chromosomal type of CPM; placental dysfunction was seen predominantly in high-risk CPM pregnancies in which chromosomes 2, 3, 7, 13 or 16 were involved. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Persistent cornual pregnancy mimicking uterine arteriovenous malformation: a case report

BACKGROUND

Uterine arteriovenous malformation(AVM) refers to the abnormal direct traffic between uterine arteries and veins, which can be characterized by the imaging examination, showing increased uterine vascularity and arteriovenous shunting. However, similar imaging manifestations can also be seen in a variety of conditions including retained production of conception, gestational trophoblastic disease, placental polyp, and vascular neoplasm.

CASE PRESENTATION

Here we present a case of a 42-year-old woman who was suspected of suffering uterine AVM indicated by Doppler sonography and magnetic resonance imaging but was finally diagnosed with a persistent ectopic pregnancy located on the right uterine corner by pathology after laparoscopy. She recovered well after surgery.

CONCLUSION

Uterine AVM is a rare and serious condition. In general, it presents special radiological manifestations. However, when complicated with other diseases it can also be distorting. Standardized diagnosis and management are important.