Lower placental growth factor and higher free β-hCG and PAPP-A levels in the fetal circulation of near-term pregnancies complicated with severe preeclampsia

BACKGROUND

An imbalance between anti- and angiogenic factors during early placentation is key for the development of preeclampsia. Nevertheless, the majority of studies addressing this issue relate to maternal blood and not the fetal circulation.

OBJECTIVE

To measure placental growth factor (PlGF), free beta human chorionic gonadotropin (β-hCG), and pregnancy-associated plasma protein-A (PAPP-A) levels in the fetal circulation of near-term pregnancies complicated with severe preeclampsia (n = 20), and their controls matched for parity, and maternal and gestational age.

METHOD

Upon delivery, a blood sample was withdrawn from the umbilical artery and vein of each case and its control in order to measure the proposed analytes using direct fluoroimmunoassay.

RESULTS

Preeclampsia cases showed significantly lower median PlGF levels in fetal circulation as compared to controls (25.2 versus 36.9 and 23.6 versus 33.9 pg/mL, artery and vein, respectively, p < 0.05). Contrarily, cases displayed higher concentrations of PAPP-A (1024.0 versus 720.9 [median] and 1027.0 ± 298.4 versus 690.3 ± 401.9 mIU/L, artery and vein, respectively, p < 0.05), and free β-hCG (mean: 33.9 ± 4.3 versus 17.2 ± 4.0 and 30.1 ± 5.2 versus 13.7 ± 3.3 ng/mL, artery, and vein respectively, p < 0.05).

CONCLUSION

Lower PlGF and higher PAPP-A and free β-hCG levels were found in the fetal circulation of near-term severe preeclamptic pregnancies. There is a need for more research in this regard.

Predicting first trimester pregnancy outcome: derivation of a multiple marker test

OBJECTIVE

To predict first trimester pregnancy outcome using biomarkers in a multicenter cohort.

DESIGN

Case-control study.

SETTING

Three academic centers.

PATIENT(S)

Women with pain and bleeding in early pregnancy.

INTERVENTION(S)

Sera from women who were 5-12 weeks' gestational age with ectopic pregnancy (EP), viable intrauterine pregnancy (IUP), and miscarriage/spontaneous abortion (SAB) was analyzed by ELISA and immunoassay for activin A, inhibin A, P, A Disintegrin And Metalloprotease-12, pregnancy-associated plasma protein A (PAPP-A), pregnancy specific B1-glycoprotein (SP1), placental-like growth factor, vascular endothelial growth factor, glycodelin (Glyc), and hCG. Classification trees were developed to optimize sensitivity/specificity for pregnancy location and viability.

MAIN OUTCOME MEASURE(S)

Area under receiver operating characteristic curve, sensitivity, specificity, and accuracy of first trimester pregnancy outcome.

RESULT(S)

In 230 pregnancies, the combination of trees to maximize sensitivity and specificity resulted in 73% specificity (95% confidence interval (CI) 0.65-0.80) and 31% sensitivity (95% CI 0.21-0.43) for viability. Similar methods had 21% sensitivity (95% CI 0.12-0.32) and 33% specificity (95% CI 0.26-0.41) for location. Activin A, Glyc, and A Disintegrin And Metalloprotease-12 definitively classified pregnancy location in 29% of the sample with 100% accuracy for EP. Progesterone and PAPP-A classified the viability in 61% of the sample with 94% accuracy.

CONCLUSION(S)

Multiple marker panels can distinguish pregnancy location and viability in a subset of women at risk for early pregnancy complications. This strategy of combining markers to maximize sensitivity and specificity results in high accuracy in a subset of subjects. Activin A, ADAM12, and Glyc are the most promising markers for pregnancy location; P and PAPP-A for viability.

Prediction of stillbirth from placental growth factor at 11-13 weeks

OBJECTIVES

To investigate whether the addition of maternal serum placental growth factor (PlGF) measured at 11-13 weeks' gestation improves the performance of screening for stillbirths that is achieved by a combination of maternal factors and first-trimester biomarkers such as maternal serum pregnancy-associated plasma protein-A (PAPP-A), fetal ductus venosus pulsatility index for veins (DV-PIV) and uterine artery pulsatility index (UtA-PI) and to evaluate the performance of screening with this model for all stillbirths and those due to impaired placentation and unexplained causes.

METHODS

This was a prospective screening study of 45 452 singleton pregnancies including 45 225 live births and 227 (0.49%) antepartum stillbirths; 131 (58%) were secondary to impaired placentation and 96 (42%) were due to other or unexplained causes. Multivariable logistic regression analysis was used to determine whether the addition of maternal serum PlGF improved the performance of screening that was achieved by a combination of maternal factors and PAPP-A, DV-PIV and UtA-PI.

RESULTS

Significant contribution to the prediction of stillbirth was provided by maternal factor-derived a-priori risk and multiples of the median values of PlGF, DV-PIV and UtA-PI but not of serum PAPP-A. A model combining these variables predicted 42% of all stillbirths and 61% of those due to impaired placentation, at a false-positive rate of 10%; within the impaired placentation group the detection rate of stillbirth < 32 weeks' gestation was higher than that of stillbirth ≥ 37 weeks (71% vs 46%; P = 0.031).

CONCLUSIONS

A high proportion of stillbirths due to impaired placentation can be identified effectively in the first trimester of pregnancy. Addition of PlGF improves the performance of screening achieved by other maternal factors and biomarkers. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

A Plaque Disruption Index Identifies Patients with Non-STE-Type 1 Myocardial Infarction within 24 Hours of Troponin Positivity

Background

Markers of plaque destabilization and disruption may have a role in identifying non-STE- type 1 Myocardial Infarction in patients presenting with troponin elevation. We hypothesized that a plaque disruption index (PDI) derived from multiple biomarkers and measured within 24 hours from the first detectable troponin in patients with acute non-STE- type 1 MI (NSTEMI-A) will confirm the diagnosis and identify these patients with higher specificity when compared to individual markers and coronary angiography.

Methods

We examined 4 biomarkers of plaque destabilization and disruption: myeloperoxidase (MPO), high-sensitivity interleukin-6, myeloid-related protein 8/14 (MRP8/14) and pregnancy-associated plasma protein-A (PAPP-A) in 83 consecutive patients in 4 groups: stable non-obstructive coronary artery disease (CAD), stable obstructive CAD, NSTEMI-A (enrolled within 24 hours of troponin positivity), and NSTEMI-L (Late presentation NSTEMI, enrolled beyond the 24 hour limit). The PDI was calculated and the patients’ coronary angiograms were reviewed for evidence of plaque disruption. The diagnostic performance of the PDI and angiography were compared.

Results

Compared to other biomarkers, MPO had the highest specificity (83%) for NSTEMI-A diagnosis (P<0.05). The PDI computed from PAPP-A, MRP8/14 and MPO was higher in NSTEMI-A patients compared to the other three groups (p<0.001) and had the highest diagnostic specificity (87%) with 79% sensitivity and 86% accuracy, which were higher compared to those obtained with MPO, but did not reach statistical significance (P>0.05 for all comparisons). The PDI had higher specificity and accuracy for NSTEMI-A diagnosis compared to coronary angiography (P<0.05).

Conclusions

A PDI measured within 24 hour of troponin positivity has potential to identify subjects with acute Non-ST-elevation type 1 MI. Additional evidence using other marker combinations and investigation in a sufficiently large non-selected cohort is warranted to establish the diagnostic accuracy of the PDI and its potential role in differentiating type 1 and type 2 MI in patients presenting with troponin elevation of uncertain etiology.

First trimester PAPP-A2, PAPP-A and hCGβ in small-for-gestational-age pregnancies

BACKGROUND

Pregnancy-associated plasma protein-A2 (PAPP-A2) is a recently discovered protease that cleaves a subset of insulin-like growth factor binding proteins (IGFBP). The molecular function suggests its involvement in the IGF system that is vital for fetal growth and development. Our objectives were to establish first trimester median curves of PAPP-A2, PAPP-A and hCGβ for singleton normal pregnancies and to investigate whether an altered level of one or more of the biomarkers is associated with small-for-gestational-age (SGA) neonates before and after stratification according to maternal hypertension and/or proteinuria.

METHODS

This was a case-control study based on 985 pregnant women delivering normal-weighted neonates and 170 pregnant women delivering SGA neonates. PAPP-A2 was measured by ELISA. PAPP-A and hCGβ were measured by an automatic analyzer. Median curves from 8+1 to 14+0 were established and all concentration values were converted to multiples of the median (MoM) values.

RESULTS

Before stratification the SGA cases had unaffected PAPP-A2 MoM and hCGβ MoM levels but lower PAPP-A MoM compared with normal controls. After stratification the SGA normotensive subgroup had lower PAPP-A2 MoM and PAPP-A MoM levels than the normal normotensive subgroup. Severe preeclamptic women delivering SGA neonates had higher PAPP-A2 MoM compared to the normotensive women delivering SGA neonates.

CONCLUSIONS

Pregnant women delivering SGA neonates did not have altered levels of PAPP-A2 or hCGβ but had lower PAPP-A level in the first trimester compared with pregnant women delivering normal-weighted neonates. Pregnancies complicated with severe preeclampsia and SGA may be associated with high PAPP-A2 level.

First trimester maternal serum screening for Down's syndrome: an evaluation of the DPC Immulite 2000 free β-hCG and pregnancy-associated plasma protein-A assays

Background: Recent NICE Guidelines have emphasized the need to have in place by 2007 the capability of offering screening to all women in the first trimester using a combination of maternal age with the ultrasound marker nuchal translucency thickness (NT) and the maternal serum biochemical markers free β-hCG and pregnancy-associated plasma protein-A (PAPP-A). Laboratories will therefore need to consider how to introduce the biochemical component of screening. With the recent launch of these assays on the DPC Immulite 2000 platform, it is appropriate and timely to investigate their clinical and analytical performance on a high throughput immunoassay analyser.

Methods: Within-run and between-day precision was assessed in the normal way. Bias was assessed by comparing samples from normal pregnancies ( n = 813) and pregnancies with Down's syndrome ( n = 60) run on both the DPC system and our routine Kryptor system. Gestational day-specific medians for each marker were calculated from the unaffected population. Mathematical modelling was used to predict the clinical performance of the two markers.

Results: The within-run coefficient of variation (CV) was around 3.5% and between-day CV was around 6-8% for both assays. Comparison with EQA samples showed a 2% positive bias against the ALTM for free β-hCG and a 21% positive bias for PAPP-A, which reduced to 11% when compared with the Kryptor method mean. When compared with the Kryptor, the DPC free β-hCG showed a significant concentration-related negative bias above concentrations of 50 IU/L in both unaffected and affected pregnancy samples. After conversion to MoM in the Down's syndrome group, the DPC free β-hCG assay showed a MoM-related bias at higher MoM values. For PAPP-A a positive MoM-related bias was also evident. In cases with Down's syndrome, the median free β-hCG MoM was 1.703 for DPC and 1.698 by the Kryptor, which was not significantly different. For PAPP-A, the median MoM was 0.62 for DPC and 0.47 by the Kryptor, which was significantly ( P = 0.025) different. This difference, if real, is likely to result in a lower detection of cases with Down's syndrome. Statistical modelling techniques suggest that this would be 58% compared with the expected 67% when combined with maternal age and free β-hCG. When combined with NT, however, this would be reduced to 85% compared with the 90% expected.

Conclusions: While laboratories may find some organizational benefit from running first trimester Down's syndrome screening on such routine high-throughput immunoassay analysers, better clinical performance is likely to be achieved with alternative platforms to the DPC Immulite 2000.

Pregnancy Associated Plasma Protein-A and Placental Growth Factor in a Sub-Saharan African Population: A Nested Cross-Sectional Study

Background

Baseline distributions of pregnancy disorders’ biomarkers PlGF and PAPP-A levels are primarily based on Western European populations of Caucasian ethnicity. Differences in PAPP-A and PlGF concentrations by ethnicity have been observed, with increased levels in Afro-Caribbean, East Asian, and South Asian women. Baseline concentrations of sub-Saharan African women have not been evaluated.

Objectives

To investigate PlGF and PAPP-A in a sub-Saharan African population and assess the performance of existing reference values of PAPP-A and PlGF.

Methods

A nested cross-sectional study was conducted in two public hospitals in Accra, Ghana. Out of the original 1010 women enrolled in the cohort, 398 participants were eligible for inclusion with a normotensive singleton gestation and serum samples taken between 56–97 days of pregnancy. PAPP-A and PlGF concentrations were measured with an automated immunoassay. Multiple of the median (MoM) values corrected for gestation and maternal weight for PAPP-A and PlGF were calculated using reference values of a Dutch perinatal screening laboratory based on over 10.000 samples, and PlGF manufacturer reference values, respectively.

Results

The PAPP-A median MoM was 2.34 (interquartile range (IQR) 1.24–3.97). Median PlGF MoM was 1.25 (IQR 0.95–1.80). Median MoM values for PAPP-A and PlGF tended to be slightly different for various Ghanaian ethnic subgroups.

Conclusions

PAPP-A and PlGF MoM values appear to be substantially higher in a sub-Saharan African population compared to the Caucasian or Afro-Caribbean MoM values previously reported. The difference suggests the need for a specific correction factor for this population to avoid underestimation of risk for fetal aneuploidies or placental disorders when using PAPP-A and PlGF MoM for screening purposes.

Study protocol for the randomised controlled trial: combined multimarker screening and randomised patient treatment with ASpirin for evidence-based PREeclampsia prevention (ASPRE)

INTRODUCTION

Pre-eclampsia (PE) affects 2-3% of all pregnancies and is a major cause of maternal and perinatal morbidity and mortality. Prophylactic use of low-dose aspirin in women at risk for PE may substantially reduce the prevalence of the disease. Effective screening for PE requiring delivery before 37 weeks (preterm PE) can be provided by a combination of maternal factors, uterine artery Doppler, mean arterial pressure, maternal serum pregnancy-associated plasma protein A and placental growth factor at 11-13 weeks' gestation, with a detection rate of 75% at a false-positive rate of 10%. We present a protocol (V.6, date 25 January 2016) for the ASpirin for evidence-based PREeclampsia prevention (ASPRE) trial, which is a double-blinded, placebo-controlled, randomised controlled trial (RCT) that uses an effective PE screening programme to determine whether low-dose aspirin given to women from 11 to 13 weeks' gestation will reduce the incidence of preterm PE.

METHODS AND ANALYSIS

All eligible women attending for their first trimester scan will be invited to participate in the screening study for preterm PE. Those found to be at high risk of developing preterm PE will be invited to participate in the RCT. Further scans will be conducted for assessment of fetal growth and biomarkers. Pregnancy and neonatal outcomes will be collected and analysed. The first enrolment for the pilot study was in April 2014. As of April 2016, 26 670 women have been screened and 1760 recruited to the RCT. The study is registered on the International Standard Randomised Controlled Trial Number (ISRCTN) registry.

TRIAL REGISTRATION NUMBER

ISRCTN13633058.

Increased pregnancy-associated plasma protein A in retinal vein occlusion

OBJECTIVE

The aim of this study was to evaluate pregnancy-associated plasma protein A (PAPP-A) levels in patients with retinal vein occlusion (RVO), and to investigate its possible role as a predictive biomarker.

PATIENTS AND METHODS

The study included 26 patients with RVO and 30 age- and gender-matched healthy subjects as controls. PAPP-A levels were measured using an enzyme-linked immunosorbent assay (ELISA) kit. The PAPP-A levels in patients with RVO were compared with those in the control group using the Mann-Whitney U test.

RESULTS

The mean serum PAPP-A levels were 1.27 ± 0.46 mIU/L (mean ± standard deviation) in the RVO group and 1.14 ± 0.11 mIU/L in the control group. There was a significant difference in PAPP-A levels between RVO patients and healthy subjects (p = 0.03). Moreover, in ROC analysis comparing the RVO patients and controls, a cutoff value of 1.126 (AUC: 0.669), specificity of 63.3% and sensitivity of 76.9% were calculated for the RVO patients (p = 0.03).

CONCLUSIONS

Our data seems to support the roles of both thrombosis and atherosclerosis in the development of RVO. It is possible that PAPP-A may be involved in the pathogenesis of venous thrombosis in the retina.

Level of Pregnancy-associated Plasma Protein-A Correlates With Coronary Thin-cap Fibroatheroma Burden in Patients With Coronary Artery Disease: Novel Findings From 3-Vessel Virtual Histology Intravascular Ultrasound Assessment

Pregnancy-associated plasma protein-A (PAPP-A) level is an independent predictor of acute cardiovascular event occurrence. To test the hypothesis that increased PAPP-A levels would be associated with a higher burden of coronary thin-cap fibroatheroma (TCFA) thereby underlying the heightened risk for cardiovascular events in patients with coronary artery disease; 154 patients (462 vessels and 975 plaques) with stable angina or non-ST-segment elevation acute coronary syndrome (NSTE-ACS) referred for percutaneous coronary intervention were assessed using 3-vessel virtual histology (VH)-intravascular ultrasound (IVUS). Thin-cap fibroatheroma virtual histology was defined as focal, necrotic core (NC)-rich (≥10% of cross-sectional area) plaques in contact with the lumen, and plaque burden ≥40%. Pregnancy-associated plasma protein-A levels were determined by sandwich enzyme-linked immunosorbent assay, and patients were divided into 3 groups based on PAPP-A level tertiles. Although the highest PAPP-A level tertile was not associated with 3-vessel plaque number, it was associated with 3-vessel VH-TCFA number and necrotic core volume. Patients with ≥3 VH-TCFAs had a higher PAPP-A level than patients with 1 to 3 VH-TCFAs or without any VH-TCFA (13.3 ± 11.8 versus 7.8 ± 4.7 versus 7.4 ± 4.7 mIU/L, P < 0.001, respectively). Moreover, PAPP-A level was an independent predictor of higher total number of VH-TCFAs (OR 1.18; 95% CI 1.07-1.29, P = 0.001). This VH-IVUS study demonstrated, for the first time to our knowledge, that higher PAPP-A levels are associated with higher 3-vessel TCFA burden in patients with coronary artery disease. Pregnancy-associated plasma protein-A, therefore, might be a useful serum biomarker to predict increased coronary TCFA burden and plaque instability.

First trimester maternal serum PAPP-A levels and associated pregnancy complications in intrahepatic cholestasis of pregnancy

PURPOSE

To investigate first trimester maternal serum pregnancy associated plasma protein A (PAPP-A) multiple of the median (MoM) in cases with intrahepatic cholestasis of pregnancy (ICP). Obstetric complications and relation with PAPP-A MoM were also evaluated.

MATERIALS AND METHODS

This was a retrospective case-control study. After exclusions, for each ICP case, two controls with uncomplicated singleton pregnancies were randomly selected. PAPP-A MoM of ICP cases with and without obstetric complications, and the control group were compared with each other.

RESULTS

Total incidence of ICP was 0.99 % (138/13988). The study included 113 singleton pregnant women. Rates of gestational diabetes mellitus (GDM), preeclampsia (PE), fetal growth restriction (FGR), preterm labor (PTL), and hypothyroidism in cases with ICP were 21.2%, 7.9%, 10.6%, 18.6%, and 5.3%, respectively. Median PAPP-A MoM were 0.93 in ICP group and 1.10 in control group (p > 0.05). PAPP-A MoM levels were not significantly different either between the ICP group with complicated pregnancies and the control group or between the ICP group without complicated pregnancies and the control group (p >0.05).

CONCLUSION

ICP incidence was similar to other European countries. Rates of obstetric complications expecially GDM were higher than expected in general pregnant population. ICP is not considered as pregnancy complications that have low PAPP-A MoM levels.

First trimester serum tests for Down's syndrome screening

BACKGROUND

Down's syndrome occurs when a person has three, rather than two copies of chromosome 21; or the specific area of chromosome 21 implicated in causing Down's syndrome. It is the commonest congenital cause of mental disability and also leads to numerous metabolic and structural problems. It can be life-threatening, or lead to considerable ill health, although some individuals have only mild problems and can lead relatively normal lives. Having a baby with Down's syndrome is likely to have a significant impact on family life.Noninvasive screening based on biochemical analysis of maternal serum or urine, or fetal ultrasound measurements, allows estimates of the risk of a pregnancy being affected and provides information to guide decisions about definitive testing. However, no test can predict the severity of problems a person with Down's syndrome will have.

OBJECTIVES

The aim of this review was to estimate and compare the accuracy of first trimester serum markers for the detection of Down's syndrome in the antenatal period, both as individual markers and as combinations of markers. Accuracy is described by the proportion of fetuses with Down's syndrome detected by screening before birth (sensitivity or detection rate) and the proportion of women with a low risk (normal) screening test result who subsequently had a baby unaffected by Down's syndrome (specificity).

SEARCH METHODS

We conducted a sensitive and comprehensive literature search of MEDLINE (1980 to 25 August 2011), Embase (1980 to 25 August 2011), BIOSIS via EDINA (1985 to 25 August 2011), CINAHL via OVID (1982 to 25 August 2011), The Database of Abstracts of Reviews of Effectiveness (The Cochrane Library 25 August 2011), MEDION (25 August 2011), The Database of Systematic Reviews and Meta-Analyses in Laboratory Medicine (25 August 2011), The National Research Register (Archived 2007), Health Services Research Projects in Progress database (25 August 2011). We did forward citation searching ISI citation indices, Google Scholar and PubMed 'related articles'. We did not apply a diagnostic test search filter. We also searched reference lists and published review articles.  

SELECTION CRITERIA

We included studies in which all women from a given population had one or more index test(s) compared to a reference standard (either chromosomal verification or macroscopic postnatal inspection). Both consecutive series and diagnostic case-control study designs were included. Randomised trials where individuals were randomised to different screening strategies and all verified using a reference standard were also eligible for inclusion. Studies in which test strategies were compared head-to-head either in the same women, or between randomised groups were identified for inclusion in separate comparisons of test strategies. We excluded studies if they included less than five Down's syndrome cases, or more than 20% of participants were not followed up.

DATA COLLECTION AND ANALYSIS

We extracted data as test positive or test negative results for Down's and non-Down's pregnancies allowing estimation of detection rates (sensitivity) and false positive rates (1-specificity). We performed quality assessment according to QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criteria. We used hierarchical summary ROC meta-analytical methods or random-effects logistic regression methods to analyse test performance and compare test accuracy as appropriate. Analyses of studies allowing direct and indirect comparisons between tests were undertaken.

MAIN RESULTS

We included 56 studies (reported in 68 publications) involving 204,759 pregnancies (including 2113 with Down's syndrome). Studies were generally of good quality, although differential verification was common with invasive testing of only high-risk pregnancies. We evaluated 78 test combinations formed from combinations of 18 different tests, with or without maternal age; ADAM12 (a disintegrin and metalloprotease), AFP (alpha-fetoprotein), inhibin, PAPP-A (pregnancy-associated plasma protein A, ITA (invasive trophoblast antigen), free βhCG (beta human chorionic gonadotrophin), PlGF (placental growth factor), SP1 (Schwangerschafts protein 1), total hCG, progesterone, uE3 (unconjugated oestriol), GHBP (growth hormone binding protein), PGH (placental growth hormone), hyperglycosylated hCG, ProMBP (proform of eosinophil major basic protein), hPL (human placental lactogen), (free αhCG, and free ßhCG to AFP ratio. Direct comparisons between two or more tests were made in 27 studies.Meta-analysis of the nine best performing or frequently evaluated test combinations showed that a test strategy involving maternal age and a double marker combination of PAPP-A and free ßhCG significantly outperformed the individual markers (with or without maternal age) detecting about seven out of every 10 Down's syndrome pregnancies at a 5% false positive rate (FPR). Limited evidence suggested that marker combinations involving PAPP-A may be more sensitive than those without PAPP-A.

AUTHORS' CONCLUSIONS

Tests involving two markers in combination with maternal age, specifically PAPP-A, free βhCG and maternal age are significantly better than those involving single markers with and without age. They detect seven out of 10 Down's affected pregnancies for a fixed 5% FPR. The addition of further markers (triple tests) has not been shown to be statistically superior; the studies included are small with limited power to detect a difference.The screening blood tests themselves have no adverse effects for the woman, over and above the risks of a routine blood test. However some women who have a 'high risk' screening test result, and are given amniocentesis or chorionic villus sampling (CVS) have a risk of miscarrying a baby unaffected by Down's. Parents will need to weigh up this risk when deciding whether or not to have an amniocentesis or CVS following a 'high risk' screening test result.

First-trimester 3-dimensional power Doppler placental vascularization indices from the whole placenta versus the placental bed to predict preeclampsia: does pregnancy-associated plasma protein a or uterine artery Doppler sonography help?

OBJECTIVES

The purpose of this study was to compare the use of vascular indices derived from the whole placenta to those from the placental bed only for predicting preeclampsia and to determine whether the addition of pregnancy-associated plasma protein A (PAPP-A) and mean uterine artery Doppler values improves prediction.

METHODS

We conducted a secondary analysis of a prospective cohort of women with singletons between 11 and 14 weeks' gestation undergoing sonography for aneuploidy screening. Placental vascularization indices from the whole placenta versus the placental bed were combined with first-trimester maternal serum PAPP-A levels, mean uterine artery Doppler values, or the combination of both to predict the development of preeclampsia or early preeclampsia (delivery <34 weeks). The predictive ability of each vascular index was calculated by using areas under receiver operating characteristic curves. The sensitivity of the model for predicting preeclampsia and early preeclampsia at fixed false-positive rates of 10% and 20% was calculated.

RESULTS

Of 570 women, 48 (8.4%) had preeclampsia, and 10 (1.7%) had early preeclampsia. The area under the curve and sensitivity values for the prediction of preeclampsia or early preeclampsia were not different when evaluating the whole placenta versus the placental bed. Additionally, there was no significant improvement when adding PAPP-A, uterine artery Doppler values, or both. The variables in the model were more sensitive for the prediction of early preeclampsia than preeclampsia.

CONCLUSIONS

Although placental bed vascular indices are modestly predictive of preeclampsia, the addition of PAPP-A and uterine artery Doppler values to vascularization indices in the whole placenta or the placental bed did not significantly improve their predictive ability.

First trimester biochemical markers in twin pregnancies

OBJECTIVE

Our aim was to investigate the first trimester serum markers and nuchal translucency (NT) measurements in twin pregnancies in our population.

MATERIALS AND METHODS

We reviewed the results of all double tests that were performed in our hospital over a three-year period. Out of them, we selected all twins and compared them with a group of three times as many singleton controls. NT measurements and the first trimester serum markers from 49 twin pregnancies were compared to those of 147 pregnant women with normal singleton pregnancy

RESULTS

There were no statistically significant differences in age, gestational age and maternal weight between the two groups (p > 0.05). We found similar NT measurements in the two groups. The median MoM of Pregnancy-Associated Plasma Protein A (PAPP-A) and fβ-hCG levels in twins were statistically significantly higher than those in singleton pregnancies. Twelve percent of the twins (12.2%) were the result of assisted reproduction technologies. IVF versus naturally conceived pregnancies showed similar MoM of PAPP-A (2.2 vs. 1.2, respectively) and fβ-hCG (Mann-Whitney U; p = 0.195 and p = 0.958).

CONCLUSIONS

Our study revealed that median PAPP-A and fβ-hCG levels for twins were less than twice those of singleton values.

[Prenatal screening for anueploidies in the first trimester: Audit to a Fetal Medicine Centre with specialized Laboratory in Mexico]

BACKGROUND

Screening for aneuploidies using ultrasound and biochemical first trimester markers has an expected performance if the qualification requirements are fulfilled.

OBJECTIVE

To describe the first trimester markers in Mexico through the audit to a Fetal Medicine Centre and Laboratory.

MATERIAL AND METHOD

Descriptive study conducted with the audit method of ultrasound and biochemical markers in pregnancies that prenatal screening tests in the first quarter were made between 11 + 1 and 14 + 1 weeks pregnant patients who came to the Laboratorio del Centro Médico para Atención Fetal Especializada.

RESULTS

In 17 months n=1020 pregnancies, 962 (94.3%) single, 55 (5.4%) doubles, and 3 (0.3%) triplets. Median maternal age of 33.8 years (16-52), 413 (40.5%) > or = 35 years. 1080 foetuses with 1009 valid measurements of nuchal translucency (29.8% at external cabinets), 54% >p50; 7.3% >p95, and 1.6% > p99. Out of 1555 sera processed at the Laboratory (f-beta-hCG and PAPP-A, Roche), 641 (41.2%) were interpreted at external centres. In 914 sera the f-beta-hCG MoM were p50 = 0.72, 3.2% >p95; for PAPP-A, p50 = 0.89, 9.0% < p5. There were 850 combined tests, and in 745 an additional marker was added; the IP ductus venosus median was 0.99 MoM. A risk > or =1 in 100 resulted in 50 foetuses (4.6%); 27 underwent invasive procedure at our Centre, 19 normal karyotypes, and 8 abnormal as: 3 trisomy 21 and 5 diverse aneuploidies.

CONCLUSIONS

The qualification requirements are fulfilled for nuchal translucency, ductus venosus, and the combined test; 1 out of 3 invasive procedures resulted an aneuploidy; the estimated false positive rate is 3.9%. The Laboratory will adjust the median values of the biochemical markers. A cohort study has begun.

Longitudinal changes in C-reactive protein, proform of eosinophil major basic protein, and pregnancy-associated plasma protein-A during weight changes in obese children

BACKGROUND

Childhood obesity is associated with several complications, including cardiovascular comorbidity. Several biomarkers, such as high-sensitive C-reactive protein (hs-CRP), proform of eosinophil major basic protein (Pro-MBP) and pregnancy associated plasma protein-A (PAPP-A), have equally been linked to increased cardiovascular susceptibility. This study investigates these biomarkers during weight loss and regain in obese children.

MATERIALS AND METHODS

A longitudinal study during a 12-week weight loss program with a 28 months follow-up was conducted. Anthropometrics and plasma concentrations of hs-CRP, Pro-MBP, and PAPP-A were measured at baseline; at days 14, 33 and 82 during weight loss; and at months 10, 16, and 28 during follow-up.

RESULTS

Fifty-three boys and 62 girls aged 8-15 years with a median body mass index (BMI) standard deviation score (SDS) at baseline of 2.78 (boys), and 2.70 (girls) were included. Ninety children completed the weight loss program and 68 children entered the follow-up program. Pro-MBP and PAPP-A, but not hs-CRP, exhibited individual-specific levels (tracking) during weight loss and regain. The PAPP-A/Pro-MBP correlation was strong, whereas the hs-CRP/PAPP-A correlation was weak during weight fluctuations.

CONCLUSION

Hs-CRP changes reflect weight changes. PAPP-A and Pro-MBP exhibited tracking during weight perturbations and may contribute as early risk markers of cardiovascular susceptibility.

[The value of maternal first and second trimester serum data of β-hCG, PAPP-A, AFP and uE3 in the prediction of preeclampsia]

OBJECTIVE

To discover the value of combined maternal first and second-trimester serum β-hCG, pregnancy associated plasma protein A (PAPP-A), alpha-fetoprotein(AFP)and unconjugated estriol (uE3) in the prediction of preeclampsia.

METHODS

A total of 1 805 pregnant women who had antenatal care at International Peace Maternal and Child Health Hospital Affiliated to Shanghai Jiaotong University between April 2012 and June 2013 were selected prospectively by random method. According to the outcome, they were defined as the control group and the preeclampsia group (including mild and severe cases). PAPP-A and β-hCG level were measured at 10-14 gestational weeks. AFP, β-hCG and uE3 were measured at 15-20 gestational weeks. The relevance between the serological indicators and outcomes was analyzed. The value of the indicators was judged by receiver operating characteristic (ROC) and Youden index, and the relevant predictive boundary values were identified.

RESULTS

(1) Among the 1 805 cases, 1 739 women did not have hypertension(the control group), while 66 women had preeclampsia (the preeclampsia group). The incidence of preeclampsia was 3.66% (66/1 805), including 43 mild cases and 23 severe cases. (2) At 10-14 gestational weeks, the mean value of PAPP-A in the control group was (3 972 ± 2 311) mU/L, while in the preeclampsia group it was (2 837 ± 1 849)mU/L. The difference between the two groups had statistical significance (P < 0.01). The mean value of β-hCG of the control group was 55(37∼83) U/L, while in the preeclampsia group it was (57 ± 35)U/L. There was no statistical significance (P > 0.05). PAPP-A, β-hCG and AFP of mild preeclampsia cases were (3 249 ± 1 877) mU/L, (61 ± 38) U/L and (35 ± 11) µg/L respectively, and in severe cases they were(1 758 ± 1 297)mU/L, (47 ± 23)U/L and (47 ± 22)µg/L, respectively. There was statistically significant difference in PAPP-A (P < 0.05). (3) At 15-20 gestational weeks, β-hCG, AFP and uE3 in the preeclampsia group were (47 909 ± 31 396 )U/L, (38 ± 15)µg/L and (0.98 ± 0.31)µg/L respectively, and in the control group they were (39 267 ± 25 054 )U/L, (47 ± 18)µg/L and (1.17 ± 0.39) µg/L, respectively. AFP and uE3 of the preeclampsia group were lower than those in the control group and the difference was statistically significant (P < 0.05). However, β-hCG and uE3 of the mild preeclampsia cases and the severe cases had no statistical difference (P > 0.05). (4)At 10-14 gestational weeks, PAPP-A demonstrated positive relevance to the newborn weight (r = 0.068, P = 0.011) and gestational weeks at delivery (r = 0.057, P = 0.048). At 15-20 weeks, positive relevance was found between AFP and the newborn weight (r = 0.149, P = 0.000), while negative relevance was found between β-hCG and Apgar scores (r = -0.085, P = 0.024), and positive relevance was found between uE3 and gestational weeks at delivery (r = 0.086, P = 0.036). (5) PAPP-A, AFP and uE3 data were used as testing parameters to obtain the boundary values of preeclampsia prediction as follows: PAPP-A 1 831 mU/L, AFP 41 µg/L and uE3 1.04 µg/L. The specificity was 97.82% , 98.54% and 98.80% , respectively. (6) ROC was drawn and Youden index was calculated based on the joint predicative factor of PAPP-A, AFP and uE3. Youden index reached its peak (0.41) when the joint predictive factor was 0.032, meaning that the factor had the highest prediction value. The prediction value of the PAPP-A, AFP and uE3 was 0.032, with the specificity and sensitivity of 98.93% and 70.59%, respectively. The odds ratio was 2.37.

CONCLUSION

Both the individual parameter (PAPP-A, AFP and uE3) and the combined data have prediction value for preeclampsia, but the latter is more effective than any of the single parameter.

Serum pregnancy-associated plasma protein A correlates with inflammation and malnutrition in patients treated with maintenance hemodialysis

Advanced chronic kidney disease (CKD) leads to complications such as anemia, electrolyte abnormalities, bone and mineral disorder, and malnutrition-inflammation-atherosclerosis (MIA) syndrome, that result in high cardiovascu- lar mortality. One of the biomarkers associated with inflammation and cardiovascular events is pregnancy-associated plasma protein A (PAPP-A). The aim of the study was to measure serum PAPP-A in hemodialyzed CKD patients, and to investigate its correlations with the laboratory markers of the complications. We enrolled 78 consecutive stable adult CKD patients treated with maintenance hemodialysis for median period of 60 months. PAPP-A concentrations were measured with by electrochemiluminescence immunoassay. Average serum PAPP-A in hemodialyzed patients was almost two times higher than the upper reference limit. It positively correlated with N-terminal pro-brain natriuretic peptide (NT-proBNP), serum sodium, and the markers of inflammation and malnutrition. In conclusion, serum PAPP-A seems a useful biomarker associated with cardiovascular dysfunction, inflammatory state and malnutrition in hemodialysis patients.

The effect of maternal polycystic ovary morphology on first-trimester maternal serum biochemical markers of aneuploidy and fetal nuchal translucency thickness

OBJECTIVE

To evaluate the effect of maternal polycystic ovary (PCO) morphology on maternal serum free beta-human chorionic gonadotropin (β-hCG), pregnancy associated plasma protein A (PAPP-A), and nuchal translucency (NT) thickness in the first-trimester.

MATERIAL AND METHODS

A total of 92 pregnant women in the first-trimester were included in the study. Of them, 57 had PCO morphology, and 35 women constituted the control group, with apparently normal ovaries. Maternal serum free β-hCG, PAPP-A, and NT thickness were measured and compared in all patients.

RESULTS

The multiples of median (MoM) levels of serum free β-hCG were significantly higher in the PCO morphology group compared to the normal ovary group (p = 0.024). However, the MoM levels of PAPP-A were similar in both groups (p = 0.947). No difference was found between the groups in terms of fasting glucose levels and NT measurements (p = 0.976 and 0.565, respectively).

CONCLUSION

In pregnancies with maternal PCO morphology, the presence of higher maternal serum free β-hCG levels may require correction in the calculation of risks related to first-trimester screening for chromosomal abnormalities. Larger studies are needed to confirm our preliminary data.

Demographic and experiential correlates of public attitudes towards cell-free fetal DNA screening

This study seeks to inform clinical application of cell-free fetal DNA (cffDNA) screening as a novel method for prenatal trisomy detection by investigating public attitudes towards this technology and demographic and experiential characteristics related to these attitudes. Two versions of a 25-item survey assessing interest in cffDNA and existing first-trimester combined screening for either trisomy 13 and 18 or trisomy 21 were distributed among 3,164 members of the United States public. Logistic regression was performed to determine variables predictive of interest in screening options. Approximately 47% of respondents expressed an interest in cffDNA screening for trisomy 13, 18, and 21, with a majority interested in cffDNA screening as a stand-alone technique. A significantly greater percent would consider termination of pregnancy following a diagnosis of trisomy 13 or 18 (52%) over one of trisomy 21 (44%). Willingness to consider abortion of an affected pregnancy was the strongest correlate to interest in both cffDNA and first-trimester combined screening, although markedly more respondents expressed an interest in some form of screening (69% and 71%, respectively) than would consider termination. Greater educational attainment, higher income, and insurance coverage predicted interest in cffDNA screening; stronger religious identification also corresponded to decreased interest. Prior experience with disability and genetic testing was associated with increased interest in cffDNA screening. Several of these factors, in addition to advanced age and Asian race, were, in turn, predictive of respondents' increased willingness to consider post-diagnosis termination of pregnancy. In conclusion, divergent attitudes towards cffDNA screening--and prenatal options more generally--appear correlated with individual socioeconomic and religious backgrounds and experiences with disability and genetic testing. Clinical implementation and counseling for novel prenatal technologies should take these diverse stakeholder values into consideration.

Normal range of intracranial translucency in healthy Turkish pregnancies and its association with first trimester maternal serum biochemistry and ductus venosus pulsatility index.

OBJECTIVE

To measure the intracranial translucency (IT) by establishing reference ranges in uncomplicated singleton Turkish pregnancies and to evaluate the association of IT with maternal serum biochemistry, gestational week, crown-rump length (CRL) measurement, nuchal translucency (NT) and ductus venosus Doppler velocimetry.

MATERIALS AND METHODS

190 uncomplicated singleton pregnancies were included in the study. IT, NT and CRL measurements between 11-14 gestational weeks were obtained with mid-sagittal plane. Two independent measurements were taken and averaged to obtain the final measurement used in the calculations. Statistical analysis was performed with SPSS for Windows 20.0 software package. Correlation analysis was used to determine the association between IT and NT pregnancy-associated plasma protein-A (PAPP-A), free β-human chorionic gonadotropin (β-hCG) and CRL length. A p-value of <0.05 was considered statistically significant.

RESULTS

The assessment rate of IT was 167/190 (87.89%). The mean CRL length, gestational week, NT and IT measurements were 63.63±10.05 mm, 12.28±0.75 weeks, 1.23±0.43 mm (range: 0.20-2.68) and 2.29±0.49 mm (range: 0.18-3.80), respectively There was no significant correlation between IT and maternal serum PAPP-A MoM (r=-0.34, p=0.698) or maternal serum free β-hCG MoM (r=-0.79, p=0.363), respectively. There was weak but statistically significant correlation between IT with with maternal weight (r=0.172, p=0.047), CRL length (r =0.301, p<0.001), gestational week (r=0.286, p=0.001) and NT measurement (r=0.224, p=0.007), respectively. There was no significant association between IT with ductus venosus Doppler pulsatility index (r=0.108, p=0.213).

CONCLUSION

IT can be easily measured while scanning for NT. This study shows normal range values in healthy Turkish pregnancies. Consistent with recent data, our results show positive correlation with gestational week and CRL length. Maternal serum biochemistry does not have any effect on IT. Besides, our study highlights that IT is correlated with NT and adds newly to the literature that there is no correlation of IT with ductus venosus pulsatility index.

Prediction of large-for-gestation neonates with first-trimester maternal serum PAPP-A

AIM

The aim of this paper was to identify maternal/pregnancy characteristics, first trimester ultrasound parameters and biochemical indices which are significant independent predictors of large-for-gestational age (LGA) neonates.

METHODS

An Observational cross-sectional study was conducted at the Fetal Medicine Unit, Department of Obstetrics and Gynecology of the University of Udine (Italy). Seventy-two singleton pregnancies presenting for screening for chromosomal abnormalities by nuchal translucency and maternal serum biochemistry at 11-14 weeks. Linear regression was applied to develop first trimester prediction models for LGA.

RESULTS

Maternal height, parity, smoking, assisted conception and pregnancy-associated plasma protein-A were significant independent predictors of LGA. PAPP-A cut-off value expressed in MoM of 1.25 used for the study was chosen to obtain good sensitivity and specificity values.

CONCLUSION

Prediction for birthweight deviations (LGA) is feasible using data available at the routine 11-14 weeks' examination.

Low pregnancy-associated plasma protein A level in the first trimester

OBJECTIVE

To review the recent evidence behind the association of low levels (ie, below the fifth percentile) of pregnancy-associated plasma protein A (PAPP-A) with adverse perinatal outcomes and to integrate new findings with the recommendations made by the Society of Obstetricians and Gynaecologists of Canada in 2008.

QUALITY OF EVIDENCE

A review of recently published articles revealed that current evidence is sparse and mixed for the association of low PAPP-A level with small size for gestational age, preterm delivery, hypertensive disorders of pregnancy, and stillbirth. There is limited evidence that suggests an association between low PAPP-A levels and spontaneous pregnancy loss. Recent studies suggest that low PAPP-A levels are associated with abnormal placentation, which might be the root cause of the adverse perinatal outcomes of interest.

MAIN MESSAGE

The evidence behind the association of low PAPP-A levels with adverse perinatal outcomes is both lacking and mixed. However, recent data do suggest an association between low PAPP-A levels and abnormal placentation. This emerging topic currently lacks strong evidence-based guidelines, yet has potential important implications for perinatal outcomes. Collaboration with obstetric specialists regarding pregnant women who have low PAPP-A levels in the context of normal first-trimester aneuploidy screening results might aid clinical decision making about pregnancy and placental surveillance.

CONCLUSION

While the clinical meaning of a low PAPP-A level detected in the context of normal fetal aneuploidy screening remains under debate, pregnant patients with such results should be counseled that at present no strong evidence exists to justify an ongoing ultrasound surveillance program.

First-trimester aneuploidy screening: is there a maternal age at which it loses effectiveness?

OBJECTIVE

To determine the maternal age at which the likelihood of a "screen-positive" result justifies diagnostic testing.

STUDY DESIGN

A retrospective review of women who presented for first-trimester screening using nuchal translucency (NT) measurements with or without serum biochemistry between January 2000-December 2011. Using cutoffs of 1:300, 1:270, and 1:200, the Trisomy 21 (T21) screen-positive rates were stratified by maternal age.

RESULTS

A total of 6,927 women underwent first-trimester screening; women with multiple gestations and/or using donor oocytes were excluded. Of the remaining women, 4,882 had combined NT and biochemistry results, while 1,767 had NT without serum screening results. Screen-positive rates were stratified by maternal age. An increase in the screen-positive rate is noted for both groups after age 40 but is more pronounced after age 43, where the screen-positive rate is 97.8% and 63.0% using cutoffs of 1:300 for the NT and NT and Biochemistry groups, respectively.

CONCLUSION

Women undergoing first-trimester screening at age 40 have approximately 30% likelihood of screening positive for T21. This rate increases to roughly 70-90% at age 44. This information will affect the counseling of patients who are considering prenatal screening versus diagnosis.