Is serum placental growth factor more effective as a biomarker in predicting early onset preeclampsia in early second trimester than in first trimester of pregnancy?

Preeclampsia and its prediction: traditional versus contemporary predictive methods

OBJECTIVE

Preeclampsia (PE) poses a significant threat to maternal and perinatal health, so its early prediction, prevention, and management are of paramount importance to mitigate adverse pregnancy outcomes. This article provides a brief review spanning epidemiology, etiology, pathophysiology, and risk factors associated with PE, mainly discussing the emerging role of Artificial Intelligence (AI) deep learning (DL) technology in predicting PE, to advance the understanding of PE and foster the clinical application of early prediction methods.

METHODS

Our narrative review comprehensively examines the PE epidemiology, etiology, pathophysiology, risk factors and predictive approaches, including traditional models and AI deep learning technology.

RESULTS

Preeclampsia involves a wide range of biological and biochemical risk factors, among which poor uterine artery remodeling, excessive immune response, endothelial dysfunction, and imbalanced angiogenesis play important roles. Traditional PE prediction models exhibit significant limitations in sensitivity and specificity, particularly in predicting late-onset PE, with detection rates ranging from only 30% to 50%. AI models have exhibited a notable level of predictive accuracy and value across various populations and datasets, achieving detection rates of approximately 70%. Particularly, they have shown superior predictive capabilities for late-onset PE, thereby presenting novel opportunities for early screening and management of the condition.

CONCLUSION

AI DL technology holds promise in revolutionizing the prediction and management of PE. AI-based approaches offer a pathway toward more effective risk assessment methods by addressing the shortcomings of traditional prediction models. Ongoing research efforts should focus on expanding databases and validating the performance of AI in diverse populations, leading to the development of more sophisticated prediction models with improved accuracy.

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.

Accuracy of placental growth factor alone or in combination with soluble fms-like tyrosine kinase-1 or maternal factors in detecting preeclampsia in asymptomatic women in the second and third trimesters: a systematic review and meta-analysis

OBJECTIVE

This study aimed to: (1) identify all relevant studies reporting on the diagnostic accuracy of maternal circulating placental growth factor) alone or as a ratio with soluble fms-like tyrosine kinase-1), and of placental growth factor-based models (placental growth factor combined with maternal factors±other biomarkers) in the second or third trimester to predict subsequent development of preeclampsia in asymptomatic women; (2) estimate a hierarchical summary receiver-operating characteristic curve for studies reporting on the same test but different thresholds, gestational ages, and populations; and (3) select the best method to screen for preeclampsia in asymptomatic women during the second and third trimester of pregnancy by comparing the diagnostic accuracy of each method.

DATA SOURCES

A systematic search was performed through MEDLINE, Embase, CENTRAL, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform databases from January 1, 1985 to April 15, 2021.

STUDY ELIGIBILITY CRITERIA

Studies including asymptomatic singleton pregnant women at >18 weeks' gestation with risk of developing preeclampsia were evaluated. We included only cohort or cross-sectional test accuracy studies reporting on preeclampsia outcome, allowing tabulation of 2×2 tables, with follow-up available for >85%, and evaluating performance of placental growth factor alone, soluble fms-like tyrosine kinase-1- placental growth factor ratio, or placental growth factor-based models. The study protocol was registered on the International Prospective Register Of Systematic Reviews (CRD 42020162460).

METHODS

Because of considerable intra- and interstudy heterogeneity, we computed the hierarchical summary receiver-operating characteristic plots and derived diagnostic odds ratios, β, θi, and Λ for each method to compare performances. The quality of the included studies was evaluated by the QUADAS-2 tool.

RESULTS

The search identified 2028 citations, from which we selected 474 studies for detailed assessment of the full texts. Finally, 100 published studies met the eligibility criteria for qualitative and 32 for quantitative syntheses. Twenty-three studies reported on performance of placental growth factor testing for the prediction of preeclampsia in the second trimester, including 16 (with 27 entries) that reported on placental growth factor test alone, 9 (with 19 entries) that reported on the soluble fms-like tyrosine kinase-1-placental growth factor ratio, and 6 (16 entries) that reported on placental growth factor-based models. Fourteen studies reported on performance of placental growth factor testing for the prediction of preeclampsia in the third trimester, including 10 (with 18 entries) that reported on placental growth factor test alone, 8 (with 12 entries) that reported on soluble fms-like tyrosine kinase-1-placental growth factor ratio, and 7 (with 12 entries) that reported on placental growth factor-based models. For the second trimester, Placental growth factor-based models achieved the highest diagnostic odds ratio for the prediction of early preeclampsia in the total population compared with placental growth factor alone and soluble fms-like tyrosine kinase-1-placental growth factor ratio (placental growth factor-based models, 63.20; 95% confidence interval, 37.62-106.16 vs soluble fms-like tyrosine kinase-1-placental growth factor ratio, 6.96; 95% confidence interval, 1.76-27.61 vs placental growth factor alone, 5.62; 95% confidence interval, 3.04-10.38); placental growth factor-based models had higher diagnostic odds ratio than placental growth factor alone for the identification of any-onset preeclampsia in the unselected population (28.45; 95% confidence interval, 13.52-59.85 vs 7.09; 95% confidence interval, 3.74-13.41). For the third trimester, Placental growth factor-based models achieved prediction for any-onset preeclampsia that was significantly better than that of placental growth factor alone but similar to that of soluble fms-like tyrosine kinase-1-placental growth factor ratio (placental growth factor-based models, 27.12; 95% confidence interval, 21.67-33.94 vs placental growth factor alone, 10.31; 95% confidence interval, 7.41-14.35 vs soluble fms-like tyrosine kinase-1-placental growth factor ratio, 14.94; 95% confidence interval, 9.42-23.70).

CONCLUSION

Placental growth factor with maternal factors ± other biomarkers determined in the second trimester achieved the best predictive performance for early preeclampsia in the total population. However, in the third trimester, placental growth factor-based models had predictive performance for any-onset preeclampsia that was better than that of placental growth factor alone but similar to that of soluble fms-like tyrosine kinase-1-placental growth factor ratio. Through this meta-analysis, we have identified a large number of very heterogeneous studies. Therefore, there is an urgent need to develop standardized research using the same models that combine serum placental growth factor with maternal factors ± other biomarkers to accurately predict preeclampsia. Identification of patients at risk might be beneficial for intensive monitoring and timing delivery.

Analysis of serum placental growth factor levels in preeclamptic and normotensive pregnant women in Lagos, Nigeria: a worthwhile screening tool?

The clinical usefulness of serum placental growth factor (PlGF) as a predictive biomarker of preeclampsia is currently being examined. However, there are still conflicting results in the literature. We assessed the association between maternal low PlGF levels and the occurrence and severity of preeclampsia. This was an analytical cross-sectional study conducted among 60 women with preeclampsia, and an equal number of matched normotensive pregnant women. PlGF concentrations were analysed using the ELISA method. Bivariate and multivariate analysis was used to test for the association between low maternal PlGF levels and the occurrence of preeclampsia and its severity. Statistical significance was reported at p < .05. The study showed that having a low maternal PlGF level (Adjusted OR 14.23; 95%CI 8.06, 29.71) together with being primigravid (Adjusted OR 3.97; 95%CI 1.03, 6.18) and having an unbooked pregnancy (Adjusted OR 8.07; 95%CI 2.06, 19.40) were independently associated with preeclampsia. We established an association between low maternal PlGF levels and preeclampsia, but no similar association with severe preeclampsia. The use of PlGF as a potential predictive marker and a reliable screening tool may have a profound implication on the prevention of preeclampsia and the subsequent reduction in its associated morbidity and mortality.Impact statementWhat is already known on this subject? The utility of serum placental growth factor (PlGF) as a predictive biomarker of preeclampsia is currently being examined, however, there are conflicting results of its clinical usefulness in the literature.What do the results of this study add? This study that assessed the association between maternal low PlGF levels and the occurrence and severity of preeclampsia showed that having a low maternal PlGF level together with being primigravid and having an unbooked pregnancy were independently associated with the occurrence of preeclampsia. However, we were unable to establish any significant relationship between maternal PlGF and the severity of preeclampsia.What are the implications of these findings for clinical practice and/or further research? We opined that the use of PlGF as a potential predictive marker and a reliable screening tool may have a profound clinical implication on the prevention and reduction in the associated morbidity and mortality of preeclampsia. However, there is an urgent need for more robust longitudinal studies to define the regulation of placental vascular development and the clinical usefulness of maternal serum PlGF and other placental biomarkers as potential screening tools for preeclampsia among black African women.

Preeclampsia Among African American Pregnant Women: An Update on Prevalence, Complications, Etiology, and Biomarkers

Importance

Preeclampsia is a devastating disease of pregnancy associated with increased risk of fetal and maternal complications. African American pregnant women have a high prevalence of preeclampsia, but there is a need of systemic analyses of this high-risk group regarding complications, etiology, and biomarkers.

Objective

The aim of this study was to provide a synopsis of current research of preeclampsia specifically related to African American women.

Evidence Acquisition

A comprehensive search was performed in the bibliographic database PubMed with keywords "preeclampsia" and "African American."

Results

African American women with preeclampsia were at an increased risk of preterm birth, which resulted in low-birth-weight infants. Intrauterine fetal death among African American preeclamptic patients occurs at twice the rate as in other races. On the maternal side, African American mothers with preeclampsia have more severe hypertension, antepartum hemorrhage, and increased mortality. Those who survive preeclampsia have a high risk of postpartum cardiometabolic disease. Preexisting conditions (eg, systemic lupus erythematosus) and genetic mutations (eg, sickle cell disease in the mother, FVL or APOL1 mutations in the fetus) may contribute to the higher prevalence and worse outcomes in African American women. Many blood factors, for example, the ratio of proteins sFlt/PlGF, hormones, and inflammatory factors, have been studied as potential biomarkers for preeclampsia, but their specificity needs further investigation.

Conclusions

Further studies of preeclampsia among African American women addressing underlying risk factors and etiologies, coupled with identification of preeclampsia-specific biomarkers allowing early detection and intervention, will significantly improve the clinical management of this devastating disease.

Ultrasound features prior to 11 weeks' gestation and first-trimester maternal factors in prediction of hypertensive disorders of pregnancy

OBJECTIVES

Maternal hypertensive disorders (MHD), including pregnancy-induced hypertension and pre-eclampsia, are estimated to occur in 7-10% of pregnancies worldwide and have significant short- and long-term implications for both mother and fetus. This study aimed to determine the association of conventional and novel early first-trimester ultrasound measures with MHD and whether these ultrasound measures, combined with maternal characteristics and biochemistry, improve the prediction of MHD.

METHODS

This was a prospective cohort study of consecutive women with a singleton pregnancy, attending for an early (5 + 1 to 11 + 0 weeks' gestation) ultrasound examination at a private obstetric ultrasound practice between February 2016 and August 2018. Recorded ultrasound measurements included mean sac diameter, yolk sac diameter, crown-rump length, fetal heart rate (FHR), trophoblast thickness, trophoblast volume (TV) and mean uterine artery pulsatility index. Maternal biochemistry was assessed at 10-14 weeks and included beta-human chorionic gonadotropin, pregnancy-associated plasma protein-A (PAPP-A), placental growth factor (PlGF) and maternal serum alpha-fetoprotein. Regression models were fitted for each ultrasound parameter and multiples of the median (MoM) were calculated. All measures were compared between women who had a normotensive outcome and those who subsequently developed MHD. Logistic regression analysis was used to create a prediction model for MHD based on maternal characteristics, ultrasound measurements at 5 + 1 to 11 + 0 weeks' gestation and maternal biochemistry at 10-14 weeks.

RESULTS

In total, 1141 women were included in the analysis, of whom 1086 (95.2%) were normotensive at delivery and 55 (4.8%) developed MHD. Women who developed MHD weighed significantly more than did normotensive women (P < 0.0001). Mean MoM values for TV (P = 0.006), PAPP-A (P = 0.031) and PlGF (P = 0.044) were decreased significantly in pregnancies that subsequently developed MHD. The proposed logistic regression model includes maternal weight and height and MoM values for TV, FHR and PlGF, resulting in an area under the receiver-operating-characteristics curve of 0.80 (95% CI, 0.75-0.86).

CONCLUSION

The combination of maternal weight and height, TV and FHR, measured prior to 11 weeks' gestation, and first-trimester PlGF appears to have good predictive value for development of MHD later in pregnancy. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Predictive Performance of PlGF (Placental Growth Factor) for Screening Preeclampsia in Asymptomatic Women: A Systematic Review and Meta-Analysis

Preeclampsia is a systemic syndrome that seems to originate from the placenta and is associated with an imbalance between angiogenic factors in the maternal circulation. One of the well-studied and widely used factors is PlGF (placental growth factor), the levels of which drop in women destined to develop preeclampsia. This drop is known to precede the development of actual signs and symptoms of preeclampsia, thus proving to be a useful screening tool in predicting the disease. The literature varies widely in terms of the clinical usefulness of the test. We conducted a meta-analysis to study the predictive accuracy of PlGF in asymptomatic women. Our analysis included 40 studies with 3189 cases of preeclampsia and 89 498 controls. The overall predictive odds ratio of the test was 9 (6-13). Subgroup analysis evaluating various PlGF thresholds demonstrated that the predictive values were highest for PlGF levels between 80 and 120 pg/mL with a high predictive odds ratio of 25 (7-88), a sensitivity of 0.78 (95% CI, 0.67-0.86), a specificity of 0.88 (95% CI, 0.75-0.95), a positive likelihood ratio of 6.3 (95% CI, 2.7-14.7), and a negative likelihood ratio of 0.26 (95% CI, 0.16-0.42). Additionally, the accuracy was higher when the test was performed after 14 weeks of gestation (OR, 10 [7-15]) and for prediction of early onset preeclampsia (OR, 18 [9-37]). We conclude that PlGF is a useful screening tool to predict preeclampsia. Nonetheless, its utility should be judged with caution and randomized controlled trials are warranted to explore if its implementation improves perinatal outcomes in asymptomatic women.

Midpregnancy prediction of pre-eclampsia using serum biomarkers sFlt-1 and PlGF

OBJECTIVES

Pre-eclampsia remains a significant cause of morbidity and mortality. Placental biomarkers soluble Fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) have been investigated previously for their ability to predict pre-eclampsia. We compared the performance of these biomarkers for midpregnancy pre-eclampsia prediction using three different immunoassay platforms.

STUDY DESIGN

Prospective study including singleton pregnancies 19-22 weeks' gestation. Maternal bloods were collected at recruitment. Screening performances using receiver operating characteristic (ROC) curves for PlGF and sFlt-1/PlGF ratio raw data and MoM values in isolation were evaluated for three immunoassay platforms using selected cut-off values.

MAIN OUTCOME MEASURES

Pre-eclampsia was defined as early-onset (<34 weeks' at delivery) and preterm (<37 weeks' at delivery).

RESULTS

For prediction of preterm pre-eclampsia, PlGF MoM and sFlt-1/PlGF ratio MoM performed similarly, with areas under the curve (AUC), detection rates (DR) and false positive rates (FPR) for PlGF MoM and sFlt-1/PlGF ratio MoM being 0.77-0.79 and 0.71-0.74, 62.5% for both and 9.7-14.9 and 10.7-17.7, respectively. For the prediction of early-onset pre-eclampsia, sFlt-1/PlGF ratio raw data and MoM values performed similarly, with AUC, DR and FPR being 0.92-0.97 and 0.93-0.96, 100% for both, and 4.13-16.9 and 9.4-12.2, respectively.

CONCLUSIONS

For midpregnancy prediction of preterm pre-eclampsia, PlGF MoM for all three platforms and sFlt-1/PlGF ratio MoM for the two platforms that tested sFlt-1 performed similarly. For midpregnancy prediction of early-onset pre-eclampsia at midpregnancy, sFlt-1/PlGF ratio raw data and MoM values using the early-onset cut-off for the two platforms that tested sFlt-1 gave similar performance from a clinical perspective.

Placental growth factor (alone or in combination with soluble fms-like tyrosine kinase 1) as an aid to the assessment of women with suspected pre-eclampsia: systematic review and economic analysis

BACKGROUND

Pre-eclampsia (PE) prediction based on blood pressure, presence of protein in the urine, symptoms and laboratory test abnormalities can result in false-positive diagnoses. This may lead to unnecessary antenatal admissions and preterm delivery. Blood tests that measure placental growth factor (PlGF) or the ratio of soluble fms-like tyrosine kinase 1 (sFlt-1) to PlGF could aid prediction of PE if either were added to routine clinical assessment or used as a replacement for proteinuria testing.

OBJECTIVES

To evaluate the diagnostic accuracy and cost-effectiveness of PlGF-based tests for patients referred to secondary care with suspected PE in weeks 20-37 of pregnancy.

DESIGN

Systematic reviews and an economic analysis.

DATA SOURCES

Bibliographic databases including MEDLINE, EMBASE, Web of Science and The Cochrane Library and Database of Abstracts of Reviews of Effects were searched up to July 2015 for English-language references. Conferences, websites, systematic reviews and confidential company submissions were also accessed.

REVIEW METHODS

Systematic reviews of test accuracy and economic studies were conducted to inform an economic analysis. Test accuracy studies were required to include women with suspected PE and report quantitatively the accuracy of PlGF-based tests; their risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria. The economic studies review had broad eligibility criteria to capture any types of economic analysis; critical appraisal employed standard checklists consistent with National Institute for Health and Care Excellence criteria. Study selection, critical appraisal and data extraction in both reviews were performed by two reviewers.

ECONOMIC ANALYSIS

An independent economic analysis was conducted based on a decision tree model, using the best evidence available. The model evaluates costs (2014, GBP) from a NHS and Personal Social Services perspective. Given the short analysis time horizon, no discounting was undertaken.

RESULTS

Four studies were included in the systematic review of test accuracy: two on Alere's Triage^® PlGF test (Alere, Inc., San Diego, CA, USA) for predicting PE requiring delivery within a specified time and two on Roche Diagnostics' Elecsys^® sFlt-1 to PlGF ratio test (Roche Diagnostics GmbH, Mannheim, Germany) for predicting PE within a specified time. Three studies were included in the systematic review of economic studies, and two confidential company economic analyses were assessed separately. Study heterogeneity precluded meta-analyses of test accuracy or cost-analysis outcomes, so narrative syntheses were conducted to inform the independent economic model. The model predicts that, when supplementing routine clinical assessment for rule-out and rule-in of PE, the two tests would be cost-saving in weeks 20-35 of gestation, and marginally cost-saving in weeks 35-37, but with minuscule impact on quality of life. Length of neonatal intensive care unit stay was the most influential parameter in sensitivity analyses. All other sensitivity analyses had negligible effects on results.

LIMITATIONS

No head-to-head comparisons of the tests were identified. No studies investigated accuracy of PlGF-based tests when used as a replacement for proteinuria testing. Test accuracy studies were found to be at high risk of clinical review bias.

CONCLUSIONS

The Triage and Elecsys tests would save money if added to routine clinical assessment for PE. The magnitude of savings is uncertain, but the tests remain cost-saving under worst-case assumptions. Further research is required to clarify how the test results would be interpreted and applied in clinical practice.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42015017670.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Maternal endothelial damage as a disorder shared by early preeclampsia, late preeclampsia and intrauterine growth restriction

INTRODUCTION

Preeclampsia (PE) and intrauterine growth restriction (IUGR) are separate disease entities that have frequently been reported as sharing the same pathogenesis. In both of them, angiogenesis disorders and generalized endothelial damage with an accompanying inflammation are the dominant symptoms. In this study, we attempted to prove that both these processes demonstrate the same profile in early PE, late PE and IUGR patients, while the only difference is in the degree of exacerbation of the lesions.

PATIENTS, MATERIALS AND METHODS

In 167 patients divided into four groups, three of those with early PE, late PE and IUGR and one control group, fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF), high sensitive c-reactive protein (hsCRP) and fibronectin were determined. The behavior of these parameters in each of the groups was studied, and correlations between them were sought for.

RESULTS

Higher concentrations of sFlt-1, hsCRP and fibronectin and a lower concentration of PlGF were found in the study groups compared to the control group. Significant correlations were observed between the factors concerned.

CONCLUSIONS

The higher values of disordered angiogenesis markers, endothelial damage markers and inflammatory markers both in the PE and the intrauterine growth restriction (IUGR) groups suggest the existence of shared disorders in the development of these pathologies. The correlations between disordered angiogenesis markers and endothelial damage markers argue in favor of a mutual relationship between these two processes in the development of pathologies evolving as secondary to placental ischemia. The results obtained confirm that the lesion profiles are the same in both PE and IUGR patients, which can be utilized in developing common diagnostic criteria.

Second-trimester maternal serum markers in the prediction of preeclampsia

AIM

To determine whether late second-trimester maternal serum biomarkers are useful for the prediction of preeclampsia during the third trimester, a case-control study including 33 preeclamptic and 71 healthy pregnancies was conducted. Maternal serum concentrations of placental protein 13 (PP13), pregnancy-associated plasma protein (PAPP-A), pentraxin3 (PTX3), soluble FMS-like tyrosine kinase-1 (sFlt-1), myostatin and follistatin-like-3 (FSLT-3) were measured at 24-28 weeks' gestation. All the concentrations of these markers were compared between the preeclamptic and control groups. Receiver operating characteristic (ROC) curve analysis was applied to assess sensitivity and specificity of serum markers with significant difference.

RESULTS

The levels of PP13 and sFlt-1 were significantly increased and FSLT3 was significantly decreased in patients with preeclampsia. However, the concentration of PAPPA, PTX3 and myostatin did not differ significantly. In screening for preeclampsia during the third trimester by PP13, sFlt-1 and FSLT3, the detection rate was 61.3%, 48.1% and 39.1%, respectively, at 80% specificity, and the detection rate increased to 69.8% by combination of these three markers.

CONCLUSION

Maternal serum levels of PP13, sFlt-1 and FSLT3 play an important role in predicting late-onset preeclampsia, and the combination of these three markers significantly increases the detection rate for prediction.

New Predictive Model at 11+0 to 13+6 Gestational Weeks for Early-Onset Preeclampsia With Fetal Growth Restriction

The aim of the present study was to determine a predictive model for early-onset preeclampsia with fetal growth restriction (FGR) to be used at 11⁺⁰ to 13⁺⁶ gestational weeks, by combining the maternal serum level of pregnancy-associated plasma protein-A (PAPP-A), placental growth factor (PLGF), placental protein 13 (PP13), soluble endoglin (sEng), mean arterial pressure (MAP), and uterine artery Doppler. This was a retrospective cohort study of 4453 pregnant women. Uterine artery Doppler examination was conducted in the first trimester. Maternal serum PAPP-A, PLGF, PP13, and sEng were measured. Mean arterial pressure was obtained. Women were classified as with/without early-onset preeclampsia, and women with preeclampsia were classified as with/without FGR. Receiver operating characteristic analysis was performed to determine the value of the model. There were 30 and 32 pregnant women with early-onset preeclampsia with and without FGR. The diagnosis rate of early-onset preeclampsia with FGR was 67.4% using the predictive model when the false positive rate was set at 5% and 73.2% when the false positive rate was 10%. The predictive model (MAP, uterine artery Doppler measurements, and serum biomarkers) had some predictive value for the early diagnosis (11⁺⁰ to 13⁺⁶ gestational weeks) of early-onset preeclampsia with FGR.

Predictive value of miR-210 as a novel biomarker for pre-eclampsia: a systematic review protocol

INTRODUCTION

Pre-eclampsia (PE) is a serious condition affecting 3-5% of all pregnancies worldwide. However, underlying molecular pathogenesis of this disease has largely remained unknown. Recently, several studies have indicated the possibility role of microRNAs, especially miR-210, in the aetiology of PE. The aim of this systematic review is to assess the possible role of miR-210 as a novel biomarker for the prediction of PE.

METHODS AND ANALYSIS

Using a combination of mesh terms 'preeclampsia', 'microRNA' and their equivalents, an electronic search will be performed for all observational studies (cross sectional, case-control and cohort) in PubMed, Web of Science, Scopus, Embase, Cochrane, LILACS and OvidSP MEDLINE from January 2005 to December 2015. Furthermore, other sources are searched, including grey literature, reference lists of relevant primary studies as well as key journals. Study selection, data extraction and quality assessment of studies will be performed independently by 2 reviewers, and any disagreement will be resolved by consensus. If sufficient data are available, it will be combined by either fixed or random effects models. We will investigate the source)s(and degree of heterogeneity using 'Heterogeneity χ2' and I2. Heterogeneity would be investigated through either subgroup analysis or metaregression. Stata V.11.1 will be used for data analysis.

ETHICS AND DISSEMINATION

The results of this study are disseminated in peer-reviewed journal articles and academic presentations. Formal ethical approval is not required, since the secondary data will be collected.

TRIAL REGISTRATION NUMBER

CRD42015032345.

Serum biomarkers combined with uterine artery Doppler in prediction of preeclampsia

First-trimester screening may be a major advantage over a second-trimester approach since it opens prospects for early and more efficient interventions. The aim of the current study was to evaluate whether the measurement of maternal serum inhibin A, activin A and placental growth factor (PlGF) at three to four months gestation with the second-trimester uterine artery pulsatility index (PI) are useful in predicting preeclampsia in a group of nulliparous women. All the patients also underwent uterine artery Doppler examination to measure the PI at 22–24 weeks gestation. Inhibin A, activin A and PlGF were measured using an ELISA by an examiner who was blinded to the pregnancy outcome. Thirty-eight cases with preeclampsia and 100 controls were analyzed. Second-trimester uterine artery PI and marker levels were expressed as multiples of the median (MoM). The uterine artery PI was increased in pregnancies with preeclampsia compared with controls. In pregnancies that developed preeclampsia, the uterine artery PI was increased (1.61±0.047 vs. 1.02±0.049, P<0.001), as was the level of inhibin A (1.72±0.023 vs. 1.03±0.063, P<0.001) and the level of activin A (1.68±0.38 vs. 1.06±0.42, P<0.001) compared with the controls. In contrast, the level of PlGF was decreased in pregnancies that developed preeclampsia compared with the controls (0.69±0.23 vs. 1.00±0.26, P<0.001). A combination of activin A, PlGF and uterine artery PI gave an AUC of 0.915 (95% CI, 0.812–0.928; P<0.001) with a sensitivity of 91% at a specificity of 82%. In our study, we demonstrated that both serum inhibin A and activin A levels were increased, while the PlGF level was decreased in the early second-trimester in women who developed preeclampsia.

Early Pregnancy Biomarkers in Pre-Eclampsia: A Systematic Review and Meta-Analysis

Pre-eclampsia (PE) complicates 2%–8% of all pregnancies and is an important cause of perinatal morbidity and mortality worldwide. In order to reduce these complications and to develop possible treatment modalities, it is important to identify women at risk of developing PE. The use of biomarkers in early pregnancy would allow appropriate stratification into high and low risk pregnancies for the purpose of defining surveillance in pregnancy and to administer interventions. We used formal methods for a systematic review and meta-analyses to assess the accuracy of all biomarkers that have been evaluated so far during the first and early second trimester of pregnancy to predict PE. We found low predictive values using individual biomarkers which included a disintegrin and metalloprotease 12 (ADAM-12), inhibin-A, pregnancy associated plasma protein A (PAPP-A), placental growth factor (PlGF) and placental protein 13 (PP-13). The pooled sensitivity of all single biomarkers was 0.40 (95% CI 0.39–0.41) at a false positive rate of 10%. The area under the Summary of Receiver Operating Characteristics Curve (SROC) was 0.786 (SE 0.02). When a combination model was used, the predictive value improved to an area under the SROC of 0.893 (SE 0.03). In conclusion, although there are multiple potential biomarkers for PE their efficacy has been inconsistent and comparisons are difficult because of heterogeneity between different studies. Therefore, there is an urgent need for high quality, large-scale multicentre research in biomarkers for PE so that the best predictive marker(s) can be identified in order to improve the management of women destined to develop PE.

Assessment of angiogenesis modulators in pregnant women with pre-eclampsia: a case-control study

PURPOSE

This study aimed to evaluate the serum concentration of factors associated with placental angiogenesis in pre-eclamptic and normotensive pregnant women.

METHODS

This was a prospective, cross-sectional, case-control study in which the pro-angiogenic factors PlGF, VEGF and IL-10, and the anti-angiogenic factors IL-6, IL-17 and TNF-α of 55 pregnant women (31 with pre-eclampsia-PE and 24 normotensive), with gestational age ≥20 weeks, were measured in maternal blood through the enzyme-linked immunosorbent assay (ELISA). The Mann-Whitney and Kruskal-Wallis tests were used for comparison between groups.

RESULTS

Serum PIGF was reduced in the group of pregnant women with PE when compared with the normotensive women (493.2 ± 55.1 pg/mL vs. 4.4 ± 26.5 pg/mL; p < 0.001). There was no significant difference in PlGF levels in the pre-eclamptic pregnant women in relation to gestational age or proteinuria levels (p > 0.05). The serum levels of VEGF, IL-17, IL-10 and TNF-α were lower in the pregnant women with PE when compared with their normotensive peers, while the IL-6 levels were higher; however, this difference was not statistically significant (p > 0.05).

CONCLUSION

Serum PlGF levels were reduced in the pregnant women with PE and were unrelated to disease severity. Serum levels of VEGF, IL-17, IL-10 and TNF-α were reduced in the pre-eclamptic pregnant women when compared with their normotensive peers, without statistically significant differences.

Second- and third-trimester biochemical and ultrasound markers predictive of ischemic placental disease

Ischemic placental disease is a recently coined term that describes the vascular insufficiency now believed to be an important etiologic factor in preeclampsia, intrauterine fetal growth restriction, and placental abruption. Given the increased risk for poor maternal and fetal outcomes, early prediction and prevention of this disorder is of significant clinical interest for many. In this article, we review the second- and third-trimester serum and ultrasound markers predictive of ischemic placental disease. Limited first-trimester data is also presented. While current studies report a statistical association between marker levels and various adverse perinatal outcomes, the observed diagnostic accuracy is below the threshold required for clinical utility. An exception to this generalization is uterine artery Doppler for the prediction of early-onset preeclampsia. Metabolomics is a relatively new analytic platform that holds promise as a first-trimester marker for the prediction of both early- and late-onset preeclampsia.