Diagnostic accuracy of first-trimester combined screening for early-onset and preterm pre-eclampsia at 8-10 compared with 11-13 weeks' gestation

Screening for pre-eclampsia with competing-risks model using placental growth factor measurement in blood samples collected before 11 weeks' gestation

OBJECTIVES

To describe the distributional properties and assess the performance of placental growth factor (PlGF) measured in blood samples collected before 11 weeks' gestation in the prediction of pre-eclampsia (PE).

METHODS

The study population consisted of pregnant women included in the Pre-eclampsia Screening in Denmark (PRESIDE) study with a PlGF measurement from the routine combined first-trimester screening (cFTS) blood sample collected at 8-14 weeks' gestation. PRESIDE was a prospective multicenter study investigating the predictive performance of the Fetal Medicine Foundation (FMF) first-trimester screening algorithm for PE in a Danish population. In the current study, serum concentration of PlGF in the cFTS blood samples was analyzed in batches between January and June 2021.

RESULTS

A total of 8386 pregnant women were included. The incidence of PE was 0.7% at < 37 weeks' gestation and 3.0% at ≥ 37 weeks. In blood samples collected at 10 weeks' gestation, PlGF multiples of the median (MoM) were significantly lower in pregnancies with preterm PE < 37 weeks compared to unaffected pregnancies. However, PlGF MoM did not differ significantly between pregnancies with PE and unaffected pregnancies in samples collected before 10 weeks' gestation.

CONCLUSIONS

The gestational-age range for PlGF sampling may be expanded from 11-14 to 10-14 weeks when assessing the risk for PE using the FMF first-trimester screening model. There is little evidence to support the use of PlGF in blood samples collected before 10 weeks' gestation. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

[Preeclampsia: Guidelines for clinical practice from the French College of Obstetricians and Gynecologists]

OBJECTIVE

To identify strategies to reduce maternal and neonatal morbidity related to preeclampsia.

MATERIAL AND METHODS

The quality of evidence of the literature was assessed following the GRADE® method with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on PubMed, Cochrane, EMBASE and Google Scholar databases. The quality of the evidence was assessed (high, moderate, low, very low) and recommendations were formulated as a (i) strong, (ii) weak or (iii) no recommendation. The recommendations were reviewed in two rounds with external reviewers (Delphi survey) to select the consensus recommendations.

RESULTS

Preeclampsia is defined by the association of gestational hypertension (systolic blood pressure≥140mmHg and/or diastolic blood pressure≥90mmHg) and proteinuria≥0.3g/24h or a Proteinuria/Creatininuria ratio≥30mg/mmol occurring after 20 weeks of gestation. Data from the literature do not show any benefit in terms of maternal or perinatal health from implementing a broader definition of preeclampsia. Of the 31 questions, there was agreement between the working group and the external reviewers on 31 (100%). In general population, physical activity during pregnancy should be encouraged to reduce the risk of preeclampsia (Strong recommendation, Quality of the evidence low) but an early screening based on algorithms (Weak recommendation, Quality of the evidence low) or aspirin administration (Weak recommendation, Quality of the evidence very low) is not recommended to reduce maternal and neonatal morbidity related to preeclampsia. In women with preexisting diabetes or hypertension or renal disease, or multiple pregnancy, the level of evidence is insufficient to determine whether aspirin administration during pregnancy is useful to reduce maternal and perinatal morbidity (No recommendation, Quality of the evidence low). In women with a history of vasculo-placental disease, low dose of aspirin (Strong recommendation, Quality of the evidence moderate) at a dosage of 100-160mg per day (Weak recommendation, Quality of the evidence low), ideally before 16 weeks of gestation and not after 20 weeks of gestation (Strong recommendation, Quality of the evidence low) until 36 weeks of gestation (Weak recommendation, Quality of the evidence very low) is recommended. In a high-risk population, additional administration of low molecular weight heparin is not recommended (Weak recommendation, Quality of the evidence moderate). In case of preeclampsia (Weak recommendation, Quality of the evidence low) or suspicion of preeclampsia (Weak recommendation, Quality of the evidence moderate, the assessment of PlGF concentration or sFLT-1/PlGF ratio is not routinely recommended) in the only goal to reduce maternal or perinatal morbidity. In women with non-severe preeclampsia antihypertensive agent should be administered orally when the systolic blood pressure is measured between 140 and 159mmHg or diastolic blood pressure is measured between 90 and 109mmHg (Weak recommendation, Quality of the evidence low). In women with non-severe preeclampsia, delivery between 34 and 36+6 weeks of gestation reduces severe maternal hypertension but increases the incidence of moderate prematurity. Taking into account the benefit/risk balance for the mother and the child, it is recommended not to systematically induce birth in women with non-severe preeclampsia between 34 and 36+6 weeks of gestation (Strong recommendation, Quality of evidence high). In women with non-severe preeclampsia diagnosed between 37+0 and 41 weeks of gestation, it is recommended to induce birth to reduce maternal morbidity (Strong recommendation, Low quality of evidence), and to perform a trial of labor in the absence of contraindication (Strong recommendation, Very low quality of evidence). In women with a history of preeclampsia, screening maternal thrombophilia is not recommended (Strong recommendation, Quality of the evidence moderate). Because women with a history of a preeclampsia have an increased lifelong risk of chronic hypertension and cardiovascular complications, they should be informed of the need for medical follow-up to monitor blood pressure and to manage other possible cardiovascular risk factors (Strong recommendation, Quality of the evidence moderate).

CONCLUSION

The purpose of these recommendations was to reassess the definition of preeclampsia, and to determine the strategies to reduce maternal and perinatal morbidity related to preeclampsia, during pregnancy but also after childbirth. They aim to help health professionals in their daily clinical practice to inform or care for patients who have had or have preeclampsia. Synthetic information documents are also offered for professionals and patients.

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.

First-trimester serum antiphosphatidylserine antibodies serve as candidate biomarkers for predicting pregnancy-induced hypertension

OBJECTIVE

The aim of this study was to explore whether antiphosphatidylserine (aPS) antibodies play roles in the early prediction of pregnancy-induced hypertension (PIH).

METHODS

The serum levels of different isotypes of aPS antibodies were compared in women diagnosed with PIH (PIH group, n  = 30) and 1 : 1 matched normotensive controls (control group, n  = 30). All patients underwent frozen embryo transfer (FET) cycles, and all serum samples were collected during 11-13 weeks of gestation. Receiver operating characteristic (ROC) curves were drawn to analyze the predictive values of aPS antibodies for PIH.

RESULTS

The women who developed PIH after FET had higher serum optical density values (450 nm) of aPS immunoglobulin (Ig) A (1.31 ± 0.43 vs. 1.02 ± 0.51, P  = 0.022), aPS IgM (1.00 ± 0.34 vs. 0.87 ± 0.18, P  = 0.046), and aPS IgG (0.50 ± 0.12 vs. 0.34 ± 0.07, P  < 0.001) compared with the normotensive controls. The serum concentration of total IgG [48.29 ± 10.71 (g/dl) vs. 34.39 ± 11.62 (g/dl), P  < 0.001] was also higher in the PIH group compared with that in the control group. The aPS IgG alone [area under the curve (AUC): 0.913, 95% confidence interval (CI): 0.842-0.985, P  < 0.001] and the combined analysis of aPS IgA, aPS IgM, aPS IgG, and total IgG (AUC: 0.944, 95% CI: 0.888-1.000, P  < 0.001) had high predictive values for PIH.

CONCLUSION

Serum aPS autoantibody levels during the first trimester of pregnancy are positively associated with the development of PIH. Further validation is needed to clearly identify the distinct contributions and underlying mechanisms for diagnostic applications of aPS autoantibodies in PIH prediction.

Predictive Performance of Machine Learning-Based Methods for the Prediction of Preeclampsia-A Prospective Study

(1) Background: Preeclampsia (PE) prediction in the first trimester of pregnancy is a challenge for clinicians. The aim of this study was to evaluate and compare the predictive performances of machine learning-based models for the prediction of preeclampsia and its subtypes. (2) Methods: This prospective case-control study evaluated pregnancies that occurred in women who attended a tertiary maternity hospital in Romania between November 2019 and September 2022. The patients' clinical and paraclinical characteristics were evaluated in the first trimester and were included in four machine learning-based models: decision tree (DT), naïve Bayes (NB), support vector machine (SVM), and random forest (RF), and their predictive performance was assessed. (3) Results: Early-onset PE was best predicted by DT (accuracy: 94.1%) and SVM (accuracy: 91.2%) models, while NB (accuracy: 98.6%) and RF (accuracy: 92.8%) models had the highest performance when used to predict all types of PE. The predictive performance of these models was modest for moderate and severe types of PE, with accuracies ranging from 70.6% and 82.4%. (4) Conclusions: The machine learning-based models could be useful tools for EO-PE prediction and could differentiate patients who will develop PE as early as the first trimester of pregnancy.

First-trimester screening for pre-eclampsia and small for gestational age: A comparison of the gaussian and Fetal Medicine Foundation algorithms

OBJECTIVE

Pre-eclampsia (PE) and small for gestational age (SGA) can be predicted from the first trimester. The most widely used algorithm worldwide is the Fetal Medicine Foundation (FMF) algorithm. The recently described Gaussian algorithm has reported excellent results although it is unlikely to be externally validated. Therefore, as an alternative approach, we compared the predictive accuracy for PE and SGA of the Gaussian and FMF algorithms.

METHODS

Secondary analysis of a prospective cohort study was conducted at Vall d'Hebron University Hospital (Barcelona) with 2641 singleton pregnancies. The areas under the curve for the predictive performance for early-onset and preterm PE and early-onset and preterm SGA were calculated with the Gaussian and FMF algorithms and subsequently compared.

RESULTS

The FMF and Gaussian algorithms showed a similar predictive performance for most outcomes and marker combinations. Nevertheless, significant differences for early-onset PE prediction favored the Gaussian algorithm in the following combinations: mean arterial blood pressure (MAP) with pregnancy-associated plasma protein A, MAP with placental growth factor, and MAP alone.

CONCLUSIONS

The first-trimester Gaussian and FMF algorithms have similar performances for PE and SGA prediction when applied with all markers within a routine care setting in a Spanish population, adding evidence to the external validity of the FMF algorithm.

Dynamic gestational week prediction model for pre-eclampsia based on ID3 algorithm

Pre-eclampsia (PE) is a type of hypertensive disorder during pregnancy, which is a serious threat to the life of mother and fetus. It is a placenta-derived disease that results in placental damage and necrosis due to systemic small vessel spasms that cause pathological changes such as ischemia and hypoxia and oxidative stress, which leads to fetal and maternal damage. In this study, four types of risk factors, namely, clinical epidemiology, hemodynamics, basic biochemistry, and biomarkers, were used for the initial selection of model parameters related to PE, and factors that were easily available and clinically recognized as being associated with a higher risk of PE were selected based on hospital medical record data. The model parameters were then further analyzed and screened in two subgroups: early-onset pre-eclampsia (EOPE) and late-onset pre-eclampsia (LOPE). Dynamic gestational week prediction model for PE using decision tree ID3 algorithm in machine learning. Performance of the model was: macro average (precision = 76%, recall = 73%, F1-score = 75%), weighted average (precision = 88%, recall = 89%, F1-score = 89%) and overall accuracy is 86%. In this study, the addition of the dynamic timeline parameter "gestational week" made the model more convenient for clinical application and achieved effective PE subgroup prediction.

Shared risk factors for COVID-19 and preeclampsia in the first trimester: An observational study

INTRODUCTION

The association between preeclampsia and coronavirus disease 2019 (COVID-19) is under study. Previous publications have hypothesized the existence of shared risk factors for both conditions or a deficient trophoblastic invasion as possible explanations for this association. The primary aim of this study was to examine baseline risk factors measured in the first-trimester combined screening for preeclampsia in pregnant women with COVID-19 compared with the general population. A secondary aim of this study was to compare risk factors among patients with mild and severe COVID-19.

MATERIAL AND METHODS

This was an observational retrospective study conducted at Vall d'Hebron Hospital Campus (Catalonia, Spain). Study patients were 231 pregnant women undergoing the first-trimester screening for preeclampsia and positive for severe acute respiratory syndrome coronavirus 2 between February 2020 and September 2021. The reference cohort were 13 033 women of the general population from six centers across Catalonia from May 2019 to June 2021. Based on the need for hospitalization, patients were classified in two groups: mild and severe COVID-19. First-trimester screening for preeclampsia included maternal history, mean arterial blood pressure, mean uterine artery pulsatility index (UtAPI), placental growth factor (PlGF), and pregnancy-associated plasma protein-A (PAPP-A).

RESULTS

The proportion of cases at high risk for preeclampsia was significantly higher among the COVID-19 group compared with the general population (19.0% and 13.2%, respectively; p = 0.012). When analyzing risk factors for preeclampsia individually, women with COVID-19 had higher median body mass index (25.2 vs 24.5, p = 0.041), higher UtAPI multiple of the median (MoM) (1.08 vs 1.00, p < 0.001), higher incidence of chronic hypertension (2.8% vs 0.9%, p = 0.015), and there were fewer smokers (5.7% vs 11.6%, p = 0.007). The MoMs of PlGF and PAPP-A did not differ significantly between both groups (0.96 vs 0.97, p = 0.760 and 1.00 vs 1.01, p = 0.432; respectively).

CONCLUSIONS

In patients with COVID-19, there was a higher proportion of women at high risk for preeclampsia at the first-trimester screening than in the general population, mainly because of maternal risk factors, rather than placental signs of a deficient trophoblastic invasion.

Evaluation of placental growth potential and placental bed perfusion by 3D ultrasound for early second-trimester prediction of preeclampsia

PURPOSE

This study aimed to investigate whether placental parameters measured by three-dimensional ultrasound are associated with preeclampsia (PE) and small-for-gestational-age (SGA).

METHODS

In total, 1163 pregnancies at 11-14 weeks of gestation were recruited between October 8, 2020, and April 30, 2021. Placenta volume (PV), placental bed vascularization flow index (PBVFI), and uterine arteries pulse index (UtA-PI) were measured. Placental quotient (PQ = PV/weeks of gestation) was calculated. All participants were re-examined 4 weeks later. The placental volume growth rate (PVGR = placental volume difference between the two examinations/interval days) was also calculated. Patients were divided into four groups by the gestational age at the onset of PE and birth weight: early-onset PE (E-PE, n = 18), late-onset PE (L-PE, n = 36), isolated SGA5 (birth weight less than the fifth percentile for gestational age without PE, n = 9), and unaffected (n = 1100) groups.

RESULTS

A predictive model for E-PE was established, which consisted of unnatural conception, chronic hypertension, PBVFI (of second examination), and PVGR for E-PE; 94.4% sensitivity and 96.7% specificity by receiver operating characteristic curve analysis.

CONCLUSIONS

Overall, decreased placental growth potential and low placental bed perfusion in the early second trimester have potential in predicting E-PE.

Implementation of routine first-trimester combined screening for preeclampsia based on the Gaussian algorithm: A clinical effectiveness study

OBJECTIVE

To evaluate the clinical effectiveness of the routine first-trimester screening for preeclampsia (PE) after being implemented in six Catalan maternities.

METHODS

Participants in the reference group were recruited prospectively between October 2015 and September 2017. Participants in the study group were recruited retrospectively between November 2018 and May 2019, after implementing the screening program. PE risk was assessed between 11 + 0 and 13 + 6 weeks of gestation using the Gaussian algorithm combining maternal characteristics, mean arterial blood pressure, uterine artery pulsatility index, and maternal serum pregnancy-associated plasma protein-A. Women with a risk ≥1/137 were prescribed daily salicylic acid (150 mg) until 36 weeks of gestation.

RESULTS

Preterm PE occurred in 30 of 2641 participants (1.14%) in the reference group, as compared with 18 of 2848 participants (0.63%) in the study group (OR: 0.55; 95% CI, 0.31-0.99; P = 0.045). In the reference group, 37 participants (1.40%) were admitted to ICU, as compared with 23 participants (0.81%) in the study group (OR: 0.57; 95% CI, 0.34-0.96; P = 0.035).

CONCLUSION

The routine first-trimester PE screening can be implemented in a public healthcare setting, leading to a significant reduction in the incidence of preterm PE and of maternal ICU admission.

Prediction of Adverse Pregnancy Outcome Related to Placental Dysfunction Using the sFlt-1/PlGF Ratio: A Narrative Review

The sFlt-1 (soluble fms-like tyrosine kinase-1)/PlGF (placental growth factor) ratio is a helpful tool for the prediction and diagnosis of preeclampsia (PE). Current data even show that the ratio has the potential to predict adverse pregnancy outcomes (APO) caused by placental pathologies. The aim of this article is to give a brief overview of recent findings on APO predictions based on the sFlt-1/PlGF ratio. The focus is on obstetric pathologies related to placental dysfunction (PD) such as PE and/or fetal growth restriction (FGR). New uses of the sFlt-1/PlGF ratio as a predictor of APO demonstrate its potential with regard to planning hospitalization and corticosteroid administration and the optimal timing of delivery. However, prospective interventional studies are warranted to define the exact role of the sFlt-1/PlGF ratio as a predictor of adverse pregnancy outcomes caused by placental pathologies.

Diagnostic accuracy of the Gaussian first-trimester combined screening for pre-eclampsia to predict small-for-gestational-age neonates

OBJECTIVE

Pre-eclampsia and delivery of small-for-gestational-age (SGA) neonates can be predicted from the first trimester. A Gaussian model for prediction of PE has recently been described, although its capacity to predict SGA is still unknown.

METHODS

This was a secondary analysis of a prospective cohort study conducted at Vall d'Hebron University Hospital (Barcelona) in 2483 single pregnancies from October 2015 to September 2017. Mean arterial blood pressure and mean uterine artery pulsatility index were recorded at the first-trimester scan. Serum concentrations of placental growth factor and pregnancy-associated plasma protein-A were assessed between 8⁺⁰ and 13⁺⁶  weeks. The predictive capacities of early (<32 weeks) and preterm (<37 weeks) SGA were tested.

RESULTS

For SGA without pre-eclampsia, detection rates of 25.0% (95% confidence interval [CI] 0-75.0) for early SGA and 14.3% (95% CI 3.6-28.6) for preterm SGA were achieved. For SGA with pre-eclampsia, the algorithm showed detection rates of 100.0% (95% CI 25.0-100.0) for early SGA and 56.3% (95% CI 31.3-81.3) for preterm SGA.

CONCLUSION

This algorithm identifies 62.5% of early SGA and 27.3% of preterm SGA. Combined screening for predicting both pre-eclampsia and SGA by using the Gaussian algorithm is feasible and would simplify clinical practice.

Prediction of hypertensive disorders in pregnancy based on placental growth factor

BACKGROUND:

The prediction of hypertensive disorders in pregnancy (HDP) mainly involves various aspects such as maternal characteristics and biomarkers.

OBJECTIVE:

We aimed to study the effect of the HDP prediction model with or without placental growth factor (PlGF).

METHODS:

This study used maternal factors and PlGF, and standardized the data uniformly. At 12–20 weeks, the comprehensive comparison of model quality with or without PlGF was conducted by logistic regression.

RESULTS:

The area under curve and the model accuracy of the model with PlGF were higher than those of the model without PlGF. The accuracy of the model with PlGF was above 90%.

CONCLUSIONS:

Adding PlGF to the model for predicting HDP improved the accuracy and effectiveness of the model. This study confirmed the predictive performance of PlGF.

High Frequency of Fetal Loss in Fetuses With Normal Karyotype and Nuchal Translucency ≥ 3 Among the Iranian Pregnant Women

Objective: The purpose of this study was comparison of association of three main first trimester screening factors with pregnancy outcomes among Iranian pregnant women.

Materials and methods: This prospective study was done during 2017-2019 years in Qazvin, Iran. To do so, a total of 1500pregnant women in first trimester were enrolled. At the first step, Nuchal translucency (NT) was measured in 11-13 ± 5 week, then the serum pregnancy-associated plasma protein A (PAPP-A) and free-β-human chorionic gonadotropin (free-β-HCG) were measured in 12-14 weeks of gestation. Pregnant women were followed up until the end of pregnancy for the complications of pregnancy such as intra-uterine growth retardation (IUGR), intrauterine death (IUFD), different types of fetal loss and preterm labor.

Results: The results showed that low levels of serum biomarkers had more association with pregnancy complications in comparison to high levels of them. Significant association of IUGR (P = 0.001), IUFD (P = 0.032) and pre-term labor (P = 0.002) was shown in women with low serum levels of PAPP-A in comparison to low serum levels of free-β-hCG. Significant high frequency of different types of fetal loss (IUFD, Abortion, Elective termination) was shown in fetuses with N ≥ 3 in comparison to low levels of serum biomarkers (P = 0.001).

Conclusion: This study highlighted the importance of accurately interpreting the results of the first trimester of pregnancy screening which should be considered by primatologists for subsequent pregnancy care.