Investigation of cardiovascular risk parameters in adolescents with metabolic syndrome

BACKGROUND

Metabolic syndrome leading to type 2 diabetes mellitus and cardiovascular diseases is a chronic multifactorial syndrome, associated with low-grade inflammation status. In our study, we aimed at assessing the serum levels of follistatin (FST), pregnancy-associated plasma protein-A (PAPP-A), and platelet/endothelial cell adhesion molecule-1 (PECAM-1) in adolescent patients with metabolic syndrome.

METHODS

This study was performed in 43 (19 males, 24 females) metabolic syndrome adolescents and 37 lean controls matched for age and sex. The serum levels of FST, PECAM-1, and PAPP-A were measured by using ELISA method.

RESULTS

Serum FST and PAPP-A levels in metabolic syndrome were significantly higher than those of controls (p < 0.005 and p < 0.05). However, there was no difference in serum PECAM-1 levels between metabolic syndrome and control groups (p = 0.927). There was a significant positive correlation between serum FST and triglyceride (r = 0.252; p < 0.05), and PAPP-A and weight, (r = 0.252; p < 0.05) in metabolic syndrome groups. Follistatin was determined statistically significant in both univariate (p = 0,008) and multivariate (p = 0,011) logistic regression analysis.

CONCLUSIONS

Our findings indicated a significant relationship between FST and PAPP-A levels and metabolic syndrome. These findings offer the possibility of using these markers in diagnosis of metabolic syndrome in adolescents as the prevention of the future complications.

Value Analysis of Four-Dimensional Color Ultrasound Combined with Maternal Serological Index in Prenatal Screening for Fetal Anomalies

Objective

This study aimed to assess the efficacy of combining four-dimensional (4D) color ultrasound with maternal serological index testing in prenatal screening for fetal anomalies.

Methods

A retrospective analysis was conducted on data from 864 pregnant women who underwent prenatal checkups at the hospital between January 2020 and January 2021. During the mid-pregnancy period, serological tests were performed to determine levels of alpha-fetoprotein (AFP), free β-subunit of human chorionic gonadotropin (Free-HCG β), pregnancy-associated plasma protein A (PAPP-A), and vitamin B12 (VitB12). Additionally, 4D color ultrasound examinations were conducted. The gold standard for evaluation was the results of delivery or labor induction. AFP, Free-HCG β, PAPP-A, and VitB12 levels were compared between the anomaly group and the normal group. The diagnostic efficacy of single and combined detection of serological indexes and 4D color ultrasound was analyzed, with the calculation of the areas under the curve (AUC) for different detection methods.

Results

Among the 864 pregnant women, 44 cases (5.09%) exhibited fetal anomalies, while 820 cases (94.91%) did not. The anomaly group showed significantly higher multiples of the median (MOM) values for AFP and Free-HCG β (P < .001) and significantly lower PAPP-A MOM and VitB12 levels (P < .001) compared to the normal group. The sensitivity of single detections for AFP MOM, Free-HCG β MOM, PAPP-A MOM, VitB12, 4D color ultrasound, and combined detection were 63.64%, 68.18%, 65.91%, 54.55%, 77.27%, and 97.93%, respectively. The corresponding AUC values were 0.805, 0.829, 0.818, 0.761, 0.885, and 0.974.

Conclusions

The combination of 4D color ultrasound with maternal serological index testing demonstrated high sensitivity in prenatal screening for fetal anomalies.

Correlation between PAPP-A serum levels in the first trimester of pregnancy with the occurrence of gestational diabetes, a multicenter cohort study

OBJECTIVE

This study aimed to investigate the association between first-trimester Pregnancy-associated plasma protein A (PAPP-A) levels and subsequent gestational diabetes mellitus (GDM) development.

METHOD

The study was conducted on 5854 pregnant women who attended routine prenatal care. Maternal biomarkers, including PAPP-A and free beta hCG, were measured for all women in a referral laboratory and converted to MoM values. Pregnant women were divided into two groups, based on the serum concentration of PAPP-A, (PAPP-A > 0.4 (normal) and PAPP-A < 0.4 (low)). Data on the screening test for GDM and pregnancy outcomes were collected and analyzed with appropriate tests.

RESULT

Of the 5854 pregnant women, 889 (15.19%) developed GDM. The maternal PAPP-A MoM concentrations were significantly lower in GDM cases compared to controls. Indeed, gestational age at delivery and birth weight were significantly lower (p < 0.001) in PAPP-A MoM < 0.4, and the rate of intrauterine growth restriction (IUGR) was significantly higher (p < 0.001). ROC analysis revealed that the sensitivity and specificity of MoM concentration for predicting GDM were 53.3% and 51.9%, respectively.

CONCLUSION

Lower maternal PAPP-A in early pregnancy can lead to glucose intolerance and increase the risk of subsequent GDM development. In addition, decreased serum concentration of PAPP-A is significantly correlated to lower birth weight and IUGR.

Clinical Application of a Graphene Oxide-Based Surface Plasmon Resonance Biosensor to Measure First-Trimester Serum Pregnancy-Associated Plasma Protein-A/A2 Ratio to Predict Preeclampsia

Background

Preeclampsia, a major cause of adverse pregnancy outcomes, involves metalloproteinases pregnancy-associated plasma protein (PAPP)-A and PAPP-A2 from placental trophoblasts. The graphene oxide (GO)-based surface plasmon resonance (SPR) biosensor has higher sensitivity, affinity, and selective ability than the traditional SPR biosensor. The aim of this study was to explore the feasibility of measuring first-trimester serum PAPP-A/PAPP-A2 ratio as a novel predictor of preeclampsia using the GO-SPR biosensor.

Methods

This prospective case-control study of pregnant women was conducted at MacKay Memorial Hospital, Taipei, Taiwan between January 2018 and June 2020. The SPR angle shifts of first-trimester serum PAPP-A, PAPP-A2, and PAPP-A/PAPP-A2 ratio measured using the GO-SPR biosensor were compared between preeclampsia and control groups.

Results

Serum samples from 185 pregnant women were collected, of whom 30 had preeclampsia (5 early-onset; 25 late-onset). The response time between the antibody-antigen association and dissociation only took about 200 seconds. The SPR angle shift of PAPP-A in the preeclampsia group was significantly smaller than that in the control group (median (interquartile range): 5.33 (4.55) versus 6.89 (4.10) millidegrees (mDeg), P = 0.008). Conversely, the SPR angle shift of PAPP-A2 in the preeclampsia group was significantly larger than that in the control group (5.70 (3.81) versus 3.63 (2.38) mDeg, P < 0.001). Receiver operating characteristic (ROC) curve analysis revealed a cut-off PAPP-A/PAPP-A2 ratio to predict all preeclampsia of ≤ 0.76, with an area under the ROC curve (AUC) of 0.79 (95% CI 0.73-0.85, P < 0.001). Sub-group analysis revealed a cut-off PAPP-A/PAPP-A2 ratio to predict early-onset preeclampsia of ≤ 0.53 (AUC 0.99, 95% CI 0.96-1.00, P < 0.001), and ≤ 0.73 to predict late-onset preeclampsia (AUC 0.75, 95% CI 0.68-0.81, P < 0.001).

Conclusion

Measuring first-trimester serum PAPP-A/PAPP-A2 ratio using the GO-SPR biosensor could be a valuable method for early prediction of preeclampsia.

Meta-analysis for the relationship between circulating pregnancy-associated plasma protein A and placenta accreta spectrum

BACKGROUND

Changes in circulating pregnancy-associated plasma protein A (PAPP-A) have been observed in women with a placenta accreta spectrum (PAS). However, no consensus has been reached according to the previous studies. Our study investigated the relationship between circulating PAPP-A and PAS risk through a systematic review and meta-analysis.

METHODS

Studies comparing the circulating level of PAPP-A between pregnant women with and without PAS were obtained by searching the Medline, Cochrane Library, Embase, CNKI, and Wanfang databases from the inception of the databases until February 12, 2023. Heterogeneity was considered in the pooling of results via a random-effects model.

RESULTS

Eight observational studies were obtained for the meta-analysis, which included 243 pregnant women with PAS and 1599 pregnant women without PAS. For all these women, the first-trimester circulating level of PAPP-A was measured by immunoassay and reported as multiples of the median (MoM) values. The pooled results showed that compared to those who did not develop PAS, women with PAS had significantly higher first-trimester serum level PAPP-A (mean difference: 0.43 MoM, 95% confidence interval [CI]: 0.30 to 0.56, P < .001; I2 = 32%). Furthermore, a high first-trimester serum PAPP-A level was related to a high PAS risk (odds ratio: 2.89, 95% CI: 2.13 to 3.92, P < .001; I2 = 0%). Sensitivity analysis which excluded one study at a time, also obtained similar results (p all < 0.05).

CONCLUSION

Pregnant women with a high serum PAPP-A level in the first trimester may be at an increased risk for PAS.

A new contingent screening strategy increased detection rate of trisomy 21 in the first trimester

BACKGROUND

Although the traditional contingent screening strategy is effective, there are still undetected low-risk trisomy 21. This study aims to define appropriate cut-off values of serum biochemical markers at low-risk and develop a strategy for sequential prenatal testing associated with first-trimester screening to increase the detection rate of trisomy 21.

METHODS

This was a 9-year retrospective analysis of singleton pregnant women who underwent serum biochemical screening or combined first-trimester screening (CFTS) in the first trimester. For the low-risk group, the cut-off values of the serum biochemical markers were adjusted to determine the appropriate detection efficiency. Gravidas with abnormal serum biochemical markers at low-risk were advised to undergo further non-invasive prenatal screening (NIPS), whereas others continued with routine prenatal care.

RESULTS

When cut-off values of free beta subunit of human chorionic gonadotropin (free β-hCG) multiples of the median (MoM) or pregnancy-associated plasma protein A (PAPP-A) MoM were defined with ≥ 2.75 or ≤ 0.5, 7.72% (2,194/28,405) in the serum biochemical screening group and 12.36% (4,005/32,403) in CFTS group could be detected as abnormal results for further NIPS. Finally, 55.56% (5/9) and 85.71% (6/7) of trisomy 21 cases with false-negative results were detected, and the overall detection rate for trisomy 21 was improved by 10.64% (5/47) and 12.77% (6/47), respectively.

CONCLUSIONS

The new contingent screening strategy can increase the detection rate of trisomy 21 compared with the traditional contingent screening strategy.

First and second-trimester biochemical serum markers in maternal familial Mediterranean fever: The impact of colchicine use

INTRODUCTION

We aimed to investigate the effects of colchicine use on first and second trimester screening markers in pregnancies complicated with familial Mediterranean fever (FMF) and to evaluate the overall impact of these effects on perinatal outcomes.

METHODS

A retrospective case-control study was conducted in pregnancies complicated with FMF using colchicine and healthy pregnancies as controls without any defined risk factors and medication use. Biochemical markers for the aneuploidy screening, including free ß-hCG and PAPP-A in the first trimester, and AFP, HCG, and unconjugated estriol (uE3) in the second trimester, were recorded, and MoM levels of these markers were compared between the FMF and control groups. Obstetric history and outcomes were also compared between groups. We used propensity score matching to form a cohort in which patients had similar baseline characteristics.

RESULTS

Among 93 eligible pregnant women, 31 women in FMF group and 31 in control group had similar propensity scores and were included in the analyses. Levels of serum-free ß-hCG, PAPP-A and AFP were similar between FMF and control groups (p = 0.671, p = 0.387 and p = 0.963, respectively). For the second-trimester markers, maternal serum uE3 MoM level were significantly lower in the FMF group using colchicine than in the controls (p = 0.045). We also compared these markers according to the daily colchicine dose between FMF subgroups. We did not detect significant difference between the different colchicine treatment modalities (0.5-1 mg/day vs. 1.5-2 mg/day, p > 0.05).

CONCLUSION

Maternal biochemical serum markers of an aneuploidy screening test in the second trimester may be affected by FMF with colchicine use, leading to misinterpretation of the risk level of tests. For these tests with decreased uE3 levels, FMF and colchicine use should be considered as a causative etiology after ruling out common etiologies and confounding factors before recommending invasive diagnostic testing.

Elevated first-trimester PAPP-A is a marker in high-risk pregnancies with an increased risk of placenta accreta in predicting adverse outcomes

OBJECTIVE

Our work aims to determine whether there is an association between first-trimester serum pregnancy-associated plasma protein A (PAPP-A) multiples of the median (MoM) value and placenta previa with or without placenta accreta spectrum disorders (PAS) in women.

PATIENTS AND METHODS

A retrospective analysis was performed on 267 patients who had first-trimester screening test results for aneuploidy, including nonadherent placenta previa (n=106), placenta previa with PAS (n=60), and control group (healthy pregnant women with previous cesarean section and normal placental location, n=101). To assess the significant difference between these groups, PAPP-A MoMs were compared.

RESULTS

The median PAPP-A MoM of 1.96 in placenta previa with PAS was significant (>0.88) in nonadherent placenta previa and 0.89 in the control group (p<0.001). Serum PAPP-A was found to be significantly associated with the severity of bleeding, such that patients with severe bleeding of 1,500 mL or more (n=54) had a higher mean PAPP-A MoM (1.93±0.69; p<0.001). Furthermore, the mean PAPP-A MoM was found to be 1.96±0.74 in the hysterectomy group and 0.89±0.47 in the conservative management group, and the difference was found to be significantly higher (p<0.001).

CONCLUSIONS

Elevated PAPP-A values in the first trimester of pregnancy may be a useful marker for identifying women at higher risk of PAS and adverse outcomes.

First-trimester screening for Down syndrome using quadruple maternal biochemical markers

OBJECTIVES

Placental growth factor (PlGF) is used for first-trimester preeclampsia screening and could be combined with other biochemical markers for Down syndrome screening. We aim to estimate the predictive value of the combination of pregnancy-associated plasma protein (PAPP-A), free β-human chorionic gonadotropin (free β-hCG), placental growth factor (PlGF) and α-fetoprotein (AFP) with and without nuchal translucency.

METHODS

Singleton pregnancies recruited at 11-14 weeks and followed until delivery. The four maternal markers were measured using Kryptor (ThermoFisher-BRAHMS) and adjusted for gestational age and maternal characteristics. The risk of Down syndrome was calculated using the Fetal Medicine Foundation algorithm and multivariate linear regression analyses in all cases and in 2,200 controls. Receiver-operator characteristic (ROC) curves were used to calculate the detection and false-positive rates.

RESULTS

Twenty-six (0.2%) cases of Down syndrome were diagnosed among 13,386 participants. The combination of the four biomarkers could have detected 88% (95% CI: 72-97%) of the cases at a false-positive rate of 13% (95% CI: 12-15%). The addition of nuchal translucency would have increased the detection rate to 96% (95% CI: 82-99%) at a false-positive rate of 4% (95% CI: 4-5%) using a 1:300 cut-off and to 100% (95% CI: 89-100%) at a false-positive rate of 6% (95% CI: 5-8%) using a 1:500 cut-off.

CONCLUSIONS

First-trimester screening using biochemical markers allows the identification of approximately 88% of Down syndrome cases for a false-positive rate of 13%. The addition of nuchal translucency raises the detection rate above 95% with a false-positive rate below 5%.

Assay interference leading to erroneous pregnancy-associated plasma protein-A results

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Prenatal Diagnosis of Congenital Heart Diseases and Associations with Serum Biomarkers of Aneuploidy: A Multicenter Prospective Cohort Study

PURPOSE

We assessed prenatal detection rates of congenital heart disease (CHD) and associations between maternal serum biomarkers and non-chromosomal CHD in singleton pregnancies.

MATERIALS AND METHODS

This study was conducted as a secondary analysis of data obtained during a multicenter prospective cohort study that investigated the cost-effectiveness of prenatal testing for fetal aneuploidy. We analyzed the prenatal detection rate and accuracy for CHD screening via ultrasound during the second trimester, as well as associations between serum biomarkers and CHDs, in singleton newborns without chromosomal abnormalities.

RESULTS

Among 6715 women, 142 (2.1%) newborns were born with CHDs, of which 67 (1.0%) newborns had major CHDs. The prenatal detection rate for all CHDs and major CHDs were 34.5% and 58.2%, respectively. After excluding isolated ventricular septal defects, the detection rate for critical CHDs was 85.9%. Women with low pregnancy-associated plasma protein A (PAPP-A) (<0.4 multiples of the median, MOM) face increased risks of non-chromosomal CHDs [adjusted odds ratio (aOR) 2.76; 95% confidence interval (CI) 1.36-5.13] and major CHDs (aOR 7.30; 95% CI 3.18-15.59), compared to those without CHDs. A higher inhibin A level (≥2.5 MOM; aOR 4.84; 95% CI 1.42-12.46) was associated with non-chromosomal major CHDs.

CONCLUSION

Ultrasonography performed during the second trimester by obstetricians detected over 85% of critical CHDs. Low maternal serum PAPP-A or high inhibin-A was associated with non-chromosomal CHDs. These results may contribute to an improvement in prenatal diagnosis of CHDs.

Fetal anatomy scan with integrated nuchal translucency and combination of PAPP-A and fβhCG for prediction of aneuploidy

BACKGROUND

Nuchal translucency (NT) is an important finding of early fetal anatomy scan because of the association with genetic and structural anomalies. Enlarged nuchal translucency can be easily detected even without measurement on fetal anatomy scan as a neck pathology. Because of demanding criteria for measurning NT in established prenatal aneuploidy screening we came with an idea of improvement and simplification with availabe methods. The aim of this study is to compare established screening methods with new model of screening composed of fetal anatomy scan with integrated nuchal translucency and combination of PAPP-A and fβhCG.

METHODS

A prospective one center study analyzed a total of 351 pregnancies between January 2017 and December 2020. Sonographic measurement of NT and fetal anatomy scan (FAS) were performend with biochemical testing from blood sample in the first trimester. Combined screening and fetal anatomy scan was performed. Patients with a pathological screening or with structural defects underwent an invasive procedure. In patient with positive screenining who missed the first trimester invasive procedure, amniocentesis was performed. Fetuses were divided into two groups according to positive or negative karyotype and to calculate sensitivity and specificity of screening methods. From statistical methods regression analysis, significance p of individual predictor, sensitivity and specificity with graphic drawing of ROC charts were used. Data were analyzed using statistical tools of Microsoft Excel 365 and BESH stat.

RESULTS

Four models for aneuploidy screening were tested. 1) Model of "Age at the time of diagnosis" was slightly significant predictor with insignificant odds ratio (P=0.04, OR=1). 2) Model of" First trimester biochemical screening" (age, free beta human chorionic gonadotropine - fβhCG and pregnancy associated plasmatic protein A - PAPP-A) were significant (P=0.0001; LR=21) with sensitivity of 87.5 % and specificity of 65.7 %. 3) Model of "First trimester combined test" (age of patients at the time of diagnosis, fβhCG, PAPP-A, NT) was significant (P=7.9 x10-14, LR=67, sensitivity 87 %, specificity 80 %). 4) Model of "Fetal anatomy scan with biochemistry" (structural abnormality finding with combination including age, fβhCG and PAPP-A) was significant (P=4.9x10-18, LR=87, sensitivity 95 %, specificity 80 %).

CONCLUSION

Fetal anatomy scan combined with age, fβhCG and PAPP-A has the highest sensitivity and specificity for both, the detection of fetal aneuploidies and structural abnormalities. Our study shows that fetal anatomy scan is the best possible option for first trimester diagnostics (Tab. 4, Fig. 5, Ref. 16).

Circulating Insulin-Like Growth Factor 1-Related Biomarkers and Risk of Lethal Prostate Cancer

Background

Experimental and epidemiologic evidence supports the role of circulating insulin-like growth factor-1 (IGF-1) levels with the risk of prostate cancer. Most circulating IGF-1 is bound to specific binding proteins, and only about 5% circulates in a free form. We explored the relation of free IGF-1 and other components of the IGF system with lethal prostate cancer.

Methods

Using prospectively collected samples, we undertook a nested case-only analysis among 434 men with lethal prostate cancer and 524 men with indolent, nonlethal prostate cancer in the Physicians’ Health Study and the Health Professionals Follow-up Study. Prediagnostic plasma samples were assayed for free IGF-1 and total IGF-1, acid labile subunit, pregnancy-associated plasma protein A (PAPP-A), and intact and total IGF binding protein 4. We estimated odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for the associations between IGF-1–related biomarkers and lethal prostate cancer using unconditional logistic regression models adjusted for age, height, and body mass index.

Results

Men in the highest quartile of PAPP-A levels had 42% higher odds of lethal prostate cancer (pooled adjusted OR = 1.42, 95% CI = 1.04 to 1.92) compared with men in the lowest 3 quartiles. There were no statistically significant differences in the other plasma analytes. The positive association between PAPP-A and lethal prostate cancer was present among men with intact PTEN but not among those with tumor PTEN loss (2-sided P_interaction = .001).

Conclusions

Our study provides suggestive evidence that among men who later develop prostate cancer, higher plasma PAPP-A levels measured prior to diagnosis are associated with increased risk of lethal compared with indolent disease.

Metabolic improvement after gastric bypass correlates with changes in IGF-regulatory proteins stanniocalcin-2 and IGFBP-4

BACKGROUND

Pregnancy-associated plasma protein-A (PAPP-A) is an enzyme that increases IGF-activity through cleavage of IGF-binding proteins (IGFBPs), primarily IGFBP-4, whereby bound IGF-I becomes released as a free molecule. The enzymatic activity of PAPP-A is irreversibly suppressed by the glycoprotein stanniocalcin-2 (STC2). Pre-clinical and clinical studies suggest that the STC2 - PAPP-A - IGFBP-4 axis is important in controlling local IGF-action. STC2, PAPP-A and IGFBP-4 are expressed in adipose tissue, and as bariatric surgery markedly reduces the amount of fat, we found it relevant to study the impact of Roux-en-Y gastric bypass (RYGB) on circulating concentrations of this IGF-regulatory network.

METHODS

Analysis of fasting blood samples from 20 obese subjects, hereof 10 with preoperative type 2 diabetes, investigated before RYGB, and 1 week, 3 months and 12 months post-surgery. Members of the IGF-system were analyzed by immunoassays, bioactive IGF by cell-based IGF-I receptor activation assay. We compared changes in IGF-system components with changes in fasting plasma insulin and glucose, and HbA1c.

RESULTS

PAPP-A remained unchanged, but STC2 decreased following RYGB (p < 0.05). The PAPP-A substrate IGFBP-4 declined (p < 0.01), whereas levels of PAPP-A specific IGFBP-4 fragments increased (p < 0.05), indicating an increased PAPP-A enzymatic activity post-RYGB. Further, the reduction in intact IGFBP-4 correlated with increased levels of bioactive IGF (p < 0.05). In multivariable regression analyses, an improved glucose metabolism correlated with reductions in STC2 and IGFBP-4, and with increases in bioactive IGF and IGF-I (p < 0.05).

CONCLUSION

After 12 months, RYGB caused reduced serum concentrations of intact IGFBP-4 and STC2, whereas serum PAPP-A remained at pre-operative levels. However, concentrations of PAPP-A generated IGFBP-4 fragments increased, pointing to an overall increased PAPP-A enzymatic activity following RYGB. Notably, reductions in intact IGFBP-4 and STC2 associated with improvements in glucose metabolism. Therefore, we propose that STC2 and IGFBP-4 are involved in the metabolic improvement that follows RYGB.

Routine first-trimester combined screening for pre-eclampsia: pregnancy-associated plasma protein-A or placental growth factor?

OBJECTIVE

To compare the screening performance of serum pregnancy-associated plasma protein-A (PAPP-A) vs placental growth factor (PlGF) in routine first-trimester combined screening for pre-eclampsia (PE), small-for-gestational age (SGA) at birth and trisomy 21.

METHODS

This was a retrospective study nested in pregnancy cohorts undergoing first-trimester combined screening for PE and trisomy 21 using The Fetal Medicine Foundation (FMF) algorithm based on maternal characteristics, nuchal translucency thickness, PAPP-A, free beta-human chorionic gonadotropin, blood pressure and uterine artery Doppler. Women at high risk for preterm PE (≥ 1 in 50) received 150 mg of aspirin per day, underwent serial fetal growth scans at 28 and 36 weeks and were offered elective birth from 40 weeks of gestation. PlGF was quantified retrospectively from stored surplus first-trimester serum samples. The performance of combined first-trimester screening for PE and SGA using maternal history, blood pressure, uterine artery pulsatility index and either PAPP-A or PlGF was calculated. Similarly, the performance of combined first-trimester screening for trisomy 21 was calculated using either PAPP-A or PlGF in addition to maternal age, nuchal translucency thickness and free beta-human chorionic gonadotropin.

RESULTS

Maternal serum PAPP-A was assayed in 1094 women, including 82 with PE, 111 with SGA (birth weight < 10^th centile), 53 with both PE and SGA and 94 with fetal trisomy 21. PlGF levels were obtained retrospectively from 1066/1094 women. Median serum PlGF multiples of the median was significantly lower in pregnancies with PE (1.0 (interquartile range (IQR), 0.8-1.4); P < 0.01), SGA (1.0 (IQR, 0.8-1.3); P < 0.001) and trisomy 21 (0.6 (IQR, 0.5-0.9); P < 0.0001) compared to in controls (1.2 (IQR, 0.9-1.5)). There was no significant difference in the performance of first-trimester screening using PAPP-A vs PlGF for either preterm PE (area under the receiver-operating-characteristics curve (AUC), 0.78 vs 0.79; P = 0.55) or term PE (AUC, 0.74 vs 0.74; P = 0.60). These findings persisted even after correction for the effect of targeted aspirin use on the prevalence of PE. Similarly, there were no significant differences in sensitivity and specificity of combined screening for SGA or trisomy 21 when using PAPP-A vs PlGF.

CONCLUSIONS

Using either PlGF or PAPP-A in routine first-trimester combined screening based on maternal characteristics, blood pressure and uterine artery Doppler does not make a significant clinical difference to the detection of PE or SGA. Depending on the setting, biomarkers should be chosen to achieve a good compromise between performance and measurement requirements. This pragmatic clinical-effectiveness study suggests that combined screening for PE can be implemented successfully in a public healthcare setting without changing current protocols for the assessment of PAPP-A in the first trimester. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

A multivariate modeling method for the prediction of low fetal fraction before noninvasive prenatal testing

OBJECTIVE

To investigate factors associated with fetal fraction and to develop a new predictive method for low fetal fraction before noninvasive prenatal testing.

METHODS

The study was a retrospective cohort analysis based on the results of noninvasive prenatal testing, complete blood count, thyroxin test, and Down's syndrome screening during the first or second trimester in 14,043 pregnant women. Random forests algorithm was applied to predict the low fetal fraction status (fetal fraction < 4%) through individual information and laboratory records. The performance of the model was evaluated and compared to predictions using maternal weight.

RESULTS

Of 14,043 cases, maternal weight, red blood cell, hemoglobin, and free T3 were significantly negatively correlated with fetal fraction while gestation age, free T4, pregnancy-associated plasma protein-A, alpha-fetoprotein, unconjugated estriol, and β-human chorionic gonadotropin were significantly positively correlated with fetal fraction. Compared to predictions using maternal weight as an isolated parameter, the model had a higher area under the curve of receiver operating characteristic and overall accuracy.

CONCLUSIONS

The comprehensive predictive method based on combined multiple factors was more effective than a single-factor model in low fetal fraction status prediction. This method can provide more pretest quality control for noninvasive prenatal testing.

Prospective evaluation of first-trimester screening strategy for preterm pre-eclampsia and its clinical applicability in China

OBJECTIVES

To evaluate, in a Chinese population, the performance of a screening strategy for preterm pre-eclampsia (PE) using The Fetal Medicine Foundation (FMF)'s competing-risks model and to explore its clinical applicability in mainland China.

METHODS

This was a prospective, multicenter, observational cohort study including 10 899 women with singleton pregnancy who sought prenatal care at one of 13 hospitals, located in seven cities in mainland China, between 1 December 2017 and 30 December 2019. Mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and maternal serum levels of placental growth factor (PlGF) and pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 to 13 + 6 weeks' gestation were measured and converted into multiples of the median using Chinese reference ranges. Individualized risk for preterm PE was calculated using the FMF algorithm. Prior risk was calculated based on maternal demographic characteristics and obstetric history. We evaluated the efficiency of the screening strategy using various combinations of biomarkers and analyzed its predictive performance for a composite of placenta-associated adverse pregnancy outcomes, including PE, placental abruption, small-for-gestational age (SGA) and preterm birth, at fixed false-positive rates for preterm PE.

RESULTS

We identified 312 pregnancies that developed PE, of which 117 cases were diagnosed as preterm PE (< 37 weeks' gestation). There were 386 pregnancies complicated by severe composite placenta-associated adverse outcome, including preterm PE, 146 cases of severe SGA (birth weight < 3^rd percentile) neonate, 61 cases with placental abruption and 109 cases of early preterm birth < 34 gestational weeks. The triple-marker model containing biomarkers MAP, UtA-PI and PAPP-A achieved, at fixed false-positive rates of 10%, 15% and 20%, detection rates for preterm PE of 65.0%, 72.7% and 76.1%, respectively, and detection rates for severe composite placenta-associated adverse outcome of 34.7%, 41.7% and 46.4%, respectively. Replacing PAPP-A with PlGF or adding PlGF to the model did not improve the performance. Of women screening positive for preterm PE at a fixed 5% false-positive rate, an estimated 30% developed at least one placenta-associated adverse pregnancy outcome, including PE, placental abruption, SGA (birth weight < 10^th percentile) and preterm birth < 37 weeks.

CONCLUSIONS

The FMF competing-risks model for preterm PE was found to be effective in screening a mainland Chinese population. Women who screened positive for preterm PE had increased risk for other placenta-associated pregnancy complications. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Fetal loss after chorionic villus sampling in twin pregnancy

OBJECTIVE

To estimate the chorionic villus sampling (CVS)-related risk of fetal loss in twin pregnancy after adjustment for chorionicity, nuchal translucency thickness (NT), intertwin discordance in crown-rump length (CRL), maternal demographic characteristics and serum pregnancy-associated plasma protein-A (PAPP-A) and free β-human chorionic gonadotropin (β-hCG).

METHODS

This was a multicenter study from eight fetal medicine units in which the leadership were trained at the Harris Birthright Research Centre for Fetal Medicine in London, UK, and in which the protocols for screening, invasive testing and pregnancy management are similar. Data were obtained prospectively from women with twin pregnancy undergoing routine ultrasound examination at 11-13 weeks' gestation. Multivariable logistic regression analysis with backward stepwise elimination was used to examine whether CVS provided a significant independent contribution to the prediction of risk of fetal loss after adjusting for maternal and pregnancy characteristics, including maternal age, racial origin and weight, method of conception, smoking status, parity, chorionicity, intertwin discordance in CRL, fetal NT ≥ 95^th percentile and free β-hCG and PAPP-A multiples of the median. Similarly, within the CVS group, multivariable logistic regression analysis was used to investigate the effect of the number of intrauterine needle insertions and size of the needle on the risk of fetal loss.

RESULTS

The study population of 8581 twin pregnancies undergoing ultrasound examination at 11-13 weeks' gestation included 316 dichorionic and 129 monochorionic twins that had CVS. First, in twin pregnancies undergoing CVS, compared to those not undergoing CVS, there was a 2-fold increased risk of fetal loss at < 24 weeks' gestation and of loss at any stage in pregnancy. Second, the factors providing a significant independent contribution to the prediction of miscarriage or fetal loss in twin pregnancy were increased maternal weight, black racial origin, monochorionicity, and more so monoamnionicity, large intertwin discordance in CRL and increased fetal NT, and, in the case of fetal loss at any stage, there was also a contribution from assisted conception and low serum PAPP-A. Third, after adjustment for maternal and pregnancy characteristics, CVS did not provide a significant contribution to the risk of fetal loss. Fourth, in twin pregnancies that had CVS, there was no significant contribution to fetal loss from the number of intrauterine needle insertions or needle size.

CONCLUSION

The 2-fold increased risk of fetal loss following CVS in twin pregnancy can, to a great extent, be explained by maternal and pregnancy characteristics rather than the invasive procedure itself. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Competing-risks model for prediction of small-for-gestational-age neonate from maternal characteristics, serum pregnancy-associated plasma protein-A and placental growth factor at 11-13 weeks' gestation

OBJECTIVES

To expand a new competing-risks model for prediction of a small-for-gestational-age (SGA) neonate, by the addition of pregnancy-associated plasma protein-A (PAPP-A) and placental growth factor (PlGF), and to evaluate and compare PAPP-A and PlGF in predicting SGA.

METHODS

This was a prospective observational study of 60 875 women with singleton pregnancy undergoing routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation. We fitted a folded-plane regression model for the PAPP-A and PlGF likelihoods. A previously developed maternal history model and the likelihood models were combined, according to Bayes' theorem, to obtain individualized distributions for gestational age (GA) at delivery and birth-weight Z-score. We assessed the discrimination and calibration of the model. McNemar's test was used to compare the detection rates for SGA with, without or independently of pre-eclampsia (PE) occurrence, of different combinations of maternal history, PAPP-A and PlGF, for a fixed false-positive rate.

RESULTS

The distributions of PAPP-A and PlGF depend on both GA at delivery and birth-weight Z-score, in the same continuous likelihood, according to a folded-plane regression model. The new approach offers the capability for risk computation for any desired birth-weight Z-score and GA at delivery cut-off. PlGF was consistently and significantly better than PAPP-A in predicting SGA delivered before 37 weeks, especially in cases with co-existence of PE. PAPP-A had similar performance to PlGF for the prediction of SGA without PE. At a fixed false-positive rate of 10%, the combination of maternal history, PlGF and PAPP-A predicted 33.8%, 43.8% and 48.4% of all cases of a SGA neonate with birth weight < 10^th percentile delivered at ≥ 37, < 37 and < 32 weeks' gestation, respectively. The respective values for birth weight < 3^rd percentile were 38.6%, 48.7% and 51.0%. The new model performed well in terms of risk calibration.

CONCLUSIONS

The combination of PAPP-A and PlGF values with maternal characteristics, according to Bayes' theorem, improves prediction of SGA. PlGF is a better predictor of SGA than PAPP-A, especially when PE is present. The new competing-risks model for SGA can be tailored to each pregnancy and to the relevant clinical requirements. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

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

OBJECTIVES

To compare the ability of first-trimester combined screening for pre-eclampsia (PE) to predict early-onset and preterm PE when pregnancy-associated plasma protein-A (PAPP-A) and placental growth factor (PlGF) were assessed before vs after 11 weeks' gestation.

METHODS

This was a secondary analysis of a prospective cohort study of singleton pregnancies undergoing routine first-trimester screening conducted at Vall d'Hebron University Hospital, Barcelona, Spain, between October 2015 and September 2017. Demographic characteristics, obstetric history, maternal history and biophysical markers (mean uterine artery pulsatility index and mean arterial blood pressure (MAP)) were recorded at the first-trimester scan (at 11 + 0 to 13 + 6 weeks' gestation). Maternal serum concentrations of PAPP-A and PlGF were assessed from the routine first-trimester blood test (at 8 + 0 to 13 + 6 weeks). Women were classified into two groups depending on whether serum biomarkers were assessed at 8 + 0 to 10 + 6 weeks or at 11 + 0 to 13 + 6 weeks. Probability scores for early-onset and preterm PE were calculated by using two different algorithms: the multivariate Gaussian-distribution model and The Fetal Medicine Foundation (FMF) competing-risks model. Receiver-operating-characteristics (ROC) curves were produced and detection rates at fixed 5% and 10% false-positive rates were computed to compare the performance of these algorithms when PAPP-A and PlGF were assessed before vs after 11 weeks.

RESULTS

Of the 2641 women included, serum biomarkers were assessed before 11 weeks in 1675 (63.4%) and at or after 11 weeks in 966 (36.6%). Of these, 90 (3.4%) women developed PE, including 11 (0.4%) cases of early-onset PE and 30 (1.1%) of preterm PE. Five (45.5%) cases of early-onset and 16 (53.3%) of preterm PE were identified in the group in which serum biomarkers were assessed at 8 + 0 to 10 + 6 weeks and six (54.5%) cases of early-onset and 14 (46.7%) of preterm PE in the group in which serum biomarkers were assessed at 11 + 0 to 13 + 6 weeks. In the prediction of early-onset and preterm PE using the Gaussian algorithm, no differences were observed between the areas under the ROC curves (AUCs) when PAPP-A and PlGF were measured before or after 11 weeks. In the prediction of early-onset and preterm PE using the FMF algorithm, no differences were observed between AUCs for any of the combinations used for risk calculation when the serum biomarkers were obtained before vs after 11 weeks, except for the combination of PAPP-A and MAP, which showed a greater AUC for the prediction of early-onset PE when PAPP-A was measured at or after 11 weeks.

CONCLUSIONS

The prediction of early-onset and preterm PE is similar when serum biomarkers are measured before or after 11 weeks. This allows the use of a two-step approach for PE risk assessment that permits immediate risk calculation at the time of the first-trimester scan. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Competing-risks model for prediction of small-for-gestational-age neonate from biophysical and biochemical markers at 11-13 weeks' gestation

OBJECTIVE

To develop a new competing-risks model for the prediction of a small-for-gestational-age (SGA) neonate, based on maternal factors and biophysical and biochemical markers at 11-13 weeks' gestation.

METHODS

This was a prospective observational study in 60 875 women with singleton pregnancy undergoing routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation. All pregnancies had pregnancy-associated plasma protein-A and placental growth factor (PlGF) measurements, 59 001 had uterine artery pulsatility index (UtA-PI) measurements and 58 479 had mean arterial pressure measurements; 57 131 cases had complete data for all biomarkers. We used a previously developed competing-risks model for the joint distribution of gestational age (GA) at delivery and birth-weight Z-score, according to maternal demographic characteristics and medical history. The likelihoods of the biophysical markers were developed by fitting folded-plane regression models, a technique that has already been used in previous studies for the likelihoods of biochemical markers. The next step was to modify the prior distribution by the likelihood, according to Bayes' theorem, to obtain individualized distributions for GA at delivery and birth-weight Z-score. We used the 57 131 cases with complete data to assess the discrimination and calibration of the model for predicting SGA with, without or independently of pre-eclampsia, by different combinations of maternal factors and biomarkers.

RESULTS

The distribution of biomarkers, conditional to both GA at delivery and birth-weight Z-score, was best described by folded-plane regression models. These continuous two-dimensional likelihoods update the joint distribution of birth-weight Z-score and GA at delivery that has resulted from a competing-risks approach; this method allows application of user-defined cut-offs. The best biophysical predictor of preterm SGA was UtA-PI and the best biochemical marker was PlGF. The prediction of SGA was consistently better for increasing degree of prematurity, greater severity of smallness, coexistence of PE and increasing number of biomarkers. The combination of maternal factors with all biomarkers predicted 34.3%, 48.6% and 59.1% of all cases of a SGA neonate with birth weight < 10^th percentile delivered at ≥ 37, < 37 and < 32 weeks' gestation, at a 10% false-positive rate. The respective values for birth weight < 3^rd percentile were 39.9%, 53.2% and 64.4%, and for birth weight < 3^rd percentile with pre-eclampsia they were 46.3%, 66.8% and 80.4%. The new model was well calibrated.

CONCLUSIONS

This study has presented a single continuous two-dimensional model for prediction of SGA for any desired cut-offs of smallness and GA at delivery, laying the ground for a personalized antenatal plan for predicting and managing SGA, in the milieu of a new inverted pyramid of prenatal care. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Competing-risks model for prediction of small-for-gestational-age neonate from maternal characteristics and serum pregnancy-associated plasma protein-A at 11-13 weeks' gestation

OBJECTIVES

To develop a continuous likelihood model for pregnancy-associated plasma protein-A (PAPP-A), in the context of a new competing-risks model for prediction of a small-for-gestational-age (SGA) neonate, and to compare the predictive performance of the new model for SGA to that of previous methods.

METHODS

This was a prospective observational study of 60 875 women with singleton pregnancy undergoing routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation. The dataset was divided randomly into a training dataset and a test dataset. The training dataset was used for PAPP-A likelihood model development. We used Bayes' theorem to combine the previously developed prior model for the joint Gaussian distribution of gestational age (GA) at delivery and birth-weight Z-score with the PAPP-A likelihood to obtain a posterior distribution. This patient-specific posterior joint Gaussian distribution of GA at delivery and birth-weight Z-score allows risk calculation for SGA defined in terms of different birth-weight percentiles and GA. The new model was validated internally in the test dataset and we compared its predictive performance to that of the risk-scoring system of the UK National Institute for Health and Care Excellence (NICE) and that of logistic regression models for different SGA definitions.

RESULTS

PAPP-A has a continuous association with both birth-weight Z-score and GA at delivery according to a folded-plane regression. The new model, with the addition of PAPP-A, was equal or superior to several logistic regression models. The new model performed well in terms of risk calibration and consistency across different GAs and birth-weight percentiles. In the test dataset, at a false-positive rate of about 30% using the criteria defined by NICE, the new model predicted 62.7%, 66.5%, 68.1% and 75.3% of cases of a SGA neonate with birth weight < 10^th percentile delivered at < 42, < 37, < 34 and < 30 weeks' gestation, respectively, which were significantly higher than the respective values of 46.7%, 55.0%, 55.9% and 52.8% achieved by application of the NICE guidelines.

CONCLUSIONS

Using Bayes' theorem to combine PAPP-A measurement data with maternal characteristics improves the prediction of SGA and performs better than logistic regression or NICE guidelines, in the context of a new competing-risks model for the joint distribution of birth-weight Z-score and GA at delivery. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

The effect of aspirin on preeclampsia, intrauterine growth restriction and preterm delivery among healthy pregnancies with a history of preeclampsia

BACKGROUND

Due to the significance of preeclampsia (PE) and its adverse outcomes in the health of both mother and newborn, the present study was carried out to investigate the effect of aspirin on preventing the occurrence of PE, intrauterine growth restriction (IUGR), and preterm delivery in women with a previous history of PE.

METHODS

The present clinical trial was conducted on 90 pregnant women with a previous history of PE referred to the Khalij Fars Hospital in Bandar Abbas, Hormozgan Province Iran from April 2017 to August 2018. The subjects of the study were randomly assigned into two groups of intervention and control to receive either 80 mg of aspirin or placebo daily during the pregnancy. Patients' information was obtained and recorded upon entering the study, follow-up visits, and childbirth.

RESULTS

Among participants who entered the clinical trial, 86 patients (95.6%) completed the study. During the pregnancy, systolic blood pressure increased by 8.25 ± 14.83 and 19.06 ± 18.33 mmHg in aspirin and placebo groups, respectively (p = 0.001). Also, the same happened with diastolic blood pressure (6.12 ± 11.46 vs 13.48 ± 13.95 mmHg, p = 0.010). The rate of PE was equal to 27 (62.8%) and 38 (88.4%) in the aspirin and placebo groups, respectively (aOR = 0.23, p = 0.013). In the aspirin group, the rate of IUGR was equal to 27.9% compared with 25.6% of newborns in the control group (aOR = 1.18, p = 0.750). Similarly, there was no significant difference in the rate of preterm delivery between the two groups (p = 0.061).

CONCLUSION

The findings of the present study conducted exclusively on women with previous documented PE revealed that taking aspirin may have a preventive effect on PE in the current pregnancy.

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.

First trimester PAPP-A serum levels and long-term metabolic outcome of mothers and their offspring

Low maternal serum levels of pregnancy associated plasma protein A (PAPP-A) are known to be associated with the development of pregnancy-related complications like small for gestational age infants, intrauterine fetal demise, gestational diabetes and preeclampsia. The study aims to find possible long-term correlations with the development of metabolic and cardiovascular complications in the mothers and their progeny in later life. This is a retrospective cohort study conducted on consecutive unselected women screened for chromosomal anomalies in the first trimester of pregnancy between 2004 and 2010. PAPP-A values as well as clinical data collected at childbirth were considered. A maternal and neonatal follow-up was performed through a telephone interview with the mother during 2015. The body-mass-index and the presence of cardiovascular diseases, dyslipidaemia and diabetes mellitus were evaluated. The analysis included 988 patients. The median time of follow-up was 7 years (IQR 6-9). Lower first trimester maternal blood PAPP-A quartiles were associated with small stature of the offspring (z-score 1st-2nd quartile 0.37 IQR -0.42 and 1.17 vs 3rd-4th quartile 0.67 IQR -0.17 and 1.36, p < 0.05). Furthermore, low first trimester PAPP-A in pregnancy without other gestations following the index one, in Kaplan-Meier analysis was associated to a significant increase of hypoglycemic agents use at 7 and 10 years (respectively 1.12% CI.95 0-2.38% and 5.45% CI.95 0-10.82%) compared to the control group of high first trimester PAPP-A values (0% CI.95 0-0%) (p < 0.05). Low PAPP-A serum levels in the first trimester of pregnancy are associated with short stature in offspring and de-novo development of maternal diabetes mellitus in later life.

First-trimester screening for trisomies in pregnancies with vanishing twin

OBJECTIVES

To examine multiples of the median (MoM) values of serum free beta-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) in a large series of pregnancies with a vanishing twin, determine the association of these values with the interval between embryonic death and blood sampling, and develop a model that would allow incorporation of these metabolites in first-trimester combined screening for trisomy.

METHODS

This was a retrospective study comparing maternal serum free β-hCG and PAPP-A levels at 11-13 weeks' gestation in 528 dichorionic pregnancies with a vanishing twin, including 194 (36.7%) with an empty gestational sac and 334 (63.3%) with a dead embryo, with those in 5280 normal singleton pregnancies matched for method of conception and date of examination. In vanishing-twin pregnancies with a dead embryo, marker levels were examined in relation to the estimated time between embryonic death and maternal blood sampling.

RESULTS

First, in pregnancies with a vanishing twin, median free β-hCG MoM was not significantly different from that in normal singleton pregnancies (1.000; 95% CI, 0.985-1.016 vs 0.995; 95% CI, 0.948-1.044; P = 0.849). Second, PAPP-A MoM was higher in vanishing-twin pregnancies than in normal singleton pregnancies (1.000; 95% CI, 0.985-1.015), both in the group with an empty gestational sac (1.165; 95% CI, 1.080-1.256; P = 0.0001) and in that with a dead embryo (1.175; 95% CI, 1.105-1.249; P < 0.0001). Third, in vanishing-twin pregnancies with a dead embryo, PAPP-A MoM was related inversely to the interval between estimated gestational age at embryonic demise and blood sampling (P < 0.0001). Fourth, in first-trimester screening for trisomy 21 in singleton pregnancies, the estimated detection rate, at a 5% false-positive rate, was 82% in screening by a combination of maternal age and fetal nuchal translucency thickness, and this increased to 86% with the addition of serum free β-hCG and to 91% with the addition of serum PAPP-A. Fifth, similar performance of screening can be achieved in pregnancies with a vanishing twin, provided the appropriate adjustments are made to the level of PAPP-A for the interval between estimated gestational age at embryonic demise and blood sampling.

CONCLUSIONS

First-trimester screening for trisomy in pregnancies with a vanishing twin should rely on a combination of maternal age, fetal nuchal translucency thickness and serum free β-hCG, as in singleton pregnancy, without the use of serum PAPP-A. Alternatively, PAPP-A can be included but only after appropriate adjustment for the interval between estimated gestational age at fetal demise and blood sampling. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Netazepide Inhibits Expression of Pappalysin 2 in Type 1 Gastric Neuroendocrine Tumors

BACKGROUND & AIMS

In patients with autoimmune atrophic gastritis and achlorhydria, hypergastrinemia is associated with the development of type 1 gastric neuroendocrine tumors (gNETs). Twelve months of treatment with netazepide (YF476), an antagonist of the cholecystokinin B receptor (CCKBR or CCK2R), eradicated some type 1 gNETs in patients. We investigated the mechanisms by which netazepide induced gNET regression using gene expression profiling.

METHODS

We obtained serum samples and gastric corpus biopsy specimens from 8 patients with hypergastrinemia and type 1 gNETs enrolled in a phase 2 trial of netazepide. Control samples were obtained from 10 patients without gastric cancer. We used amplified and biotinylated sense-strand DNA targets from total RNA and Affymetrix (Thermofisher Scientific, UK) Human Gene 2.0 ST microarrays to identify differentially expressed genes in stomach tissues from patients with type 1 gNETs before, during, and after netazepide treatment. Findings were validated in a human AGSGR gastric adenocarcinoma cell line that stably expresses human CCK2R, primary mouse gastroids, transgenic hypergastrinemic INS-GAS mice, and patient samples.

RESULTS

Levels of pappalysin 2 (PAPPA2) messenger RNA were reduced significantly in gNET tissues from patients receiving netazepide therapy compared with tissues collected before therapy. PAPPA2 is a metalloproteinase that increases the bioavailability of insulin-like growth factor (IGF) by cleaving IGF binding proteins (IGFBPs). PAPPA2 expression was increased in the gastric corpus of patients with type 1 gNETs, and immunohistochemistry showed localization in the same vicinity as CCK2R-expressing enterochromaffin-like cells. Up-regulation of PAPPA2 also was found in the stomachs of INS-GAS mice. Gastrin increased PAPPA2 expression with time and in a dose-dependent manner in gastric AGSGR cells and mouse gastroids by activating CCK2R. Knockdown of PAPPA2 in AGSGR cells with small interfering RNAs significantly decreased their migratory response and tissue remodeling in response to gastrin. Gastrin altered the expression and cleavage of IGFBP3 and IGFBP5.

CONCLUSIONS

In an analysis of human gNETS and mice, we found that gastrin up-regulates the expression of gastric PAPPA2. Increased PAPPA2 alters IGF bioavailability, cell migration, and tissue remodeling, which are involved in type 1 gNET development. These effects are inhibited by netazepide.

Can Variable Plasma Volume Alterations Affect the Efficiency of the First Trimester Screening Test?

BACKGROUND

The aim of this study was to assess the effect of plasma volume alteration determined by hematocrit on biochemical parameters of the first trimester screening test.

METHODS

Enrolled in this study were 1,424 pregnant women in their first trimester who underwent a first trimester screening test. Fetal Nuchal Trancluciency measurement was obtained by ultrasonographic evaluation. Blood samples were taken for complete blood count, serum free β-HCG, and PAPP-A between 11 and 14 weeks of gestation. The effect of plasma volume alteration on the screening test was evaluated. Mean corpuscular volume was used to rule out possible iron deficiency anemia.

RESULTS

There were 59 women with combined risk > 1/270. Of these 59 women, there were 21 false positive results (1.5%). Serum Htc significantly predicted the false positive cases (AUC: 0.839, p < 0.001). The optimal cutoff value was obtained at a value of 30.2% with 85% sensitivity and 75% specificity.

CONCLUSIONS

Our study suggests that the degree of plasma alterations may affect the serum levels of the biochemical components of the first trimester screening test for aneuploidy, thereby leading to false positive test results.

Value of Pregnancy-Associated Plasma Protein-A for Predicting Adverse Pregnancy Outcome

BACKGROUND

It is suggested that pregnancy-associated plasma protein-A (PAPP-A) levels below the fifth percentile or less than 0.4 multiples of the median (MoMs) during the first trimester are closely associated with higher risk for neonatal abnormalities. We assessed the value of PAPP-A within the first trimester for predicting pregnancy outcome.

METHODS

In a historical cohort study, we assessed 8460 consecutive pregnant women recruited for chromosomal abnormalities screening within the first trimester at Fertility Infertility and Perinatology Research Center, in Ahvaz Jundishapur University of Medical Sciences between April 2014 and April 2015. The women were categorized into two groups: pregnant women with PAPP-A levels below 0.4 multiples of MOM (n = 237) and those with higher levels of PAPP-A (n = 237).

RESULTS

The median value of MOM PAPP-A was 0.82 ± 0.78, with 237 women having MOM PAPP-A lower than 0.4. Compared to women with MOM PAPP-A higher than 0.4, those with lower MOM PAPP-A had higher mean age, lower gestational age and lower birth weight. The prevalence of small for gestational age (SGA) was higher in women with MOM PAPP-A <0.4 compared to others. According to the ROC curve analysis, MOM PAPP-A <0.4 had a high value for predicting SGA. Best cutoff value for MOM PAPP-A to predict SGA was shown to be 0.25, yielding a sensitivity of 84.7% and a specificity of 68.6.

CONCLUSION

Measuring the serum level of MOM PAPP-A during the first trimester is a valuable marker for predicting adverse outcomes of pregnancy such as SGA.

First Trimester Combined Test (FTCT) as a Predictor of Gestational Diabetes Mellitus

Background—The first trimester combined test (FTCT) is an effective screening tool to estimate the risk of fetal aneuploidy. It is obtained by the combination of maternal age, ultrasound fetal nuchal translucency (NT) measurement, and the maternal serum markers free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein A (PAPP-A). However, conflicting data have been reported about the association of FTCT, β-hCG, or PAPP-A with the subsequent diagnosis of gestational diabetes mellitus (GDM). Research design and methods—2410 consecutive singleton pregnant women were retrospectively enrolled in Calabria, Southern Italy. All participants underwent examinations for FTCT at 11–13 weeks (plus 6 days) of gestation, and screening for GDM at 16–18 and/or 24–28 weeks of gestation, in accordance with current Italian guidelines and the International Association Diabetes Pregnancy Study Groups (IADPSG) glycemic cut-offs. Data were examined by univariate and logistic regression analyses. Results—1814 (75.3%) pregnant women were normal glucose tolerant, while 596 (24.7%) were diagnosed with GDM. Spearman univariate analysis demonstrated a correlation between FTCT values and subsequent GDM diagnosis (ρ = 0.048, p = 0.018). The logistic regression analysis showed that women with a FTCT <1:10000 had a major GDM risk (p = 0.016), similar to women with a PAPP-A <1 multiple of the expected normal median (MoM, p = 0.014). Conversely, women with β-hCG ≥2.0 MoM had a reduced risk of GDM (p = 0.014). Conclusions—Our findings indicate that GDM susceptibility increases with fetal aneuploidy risk, and that FTCT and its related maternal serum parameters can be used as early predictors of GDM.

First-Trimester Biochemical Screening For Low Birth Weight: Clinical Effectiveness of Low Pregnancy-Associated Plasma Protein-A and High Thyroid-Stimulating Hormone

BACKGROUND

Low birth weight (LBW) can be an important adverse neonatal outcome in terms of morbidity and mortality. The aim of this study is to investigate the screening effectiveness of first-trimester low pregnancy-associated plasma protein A (PAPP-A) and high serum thyroid-stimulating hormone (TSH) and the combination of both markers for predicting LBW.

METHODS

We performed a retrospective cohort study of women undergoing first-trimester assessment in our center. We considered low PAPP-A as < 5th percentile for gestational age. High serum TSH was defined as > 2.5 mU/L, according to the American Thyroid Association (ATA) recommendation. Receiver-operating characteristic (ROC) curves were plotted to evaluate screening performance. Multivariate logistic regression was accomplished to calculate adjusted risks to identify the association between both parameters with LBW.

RESULTS

Overall, 4,396 women met the inclusion criteria. Of these, 277 (6.3%) delivered a LBW baby. The use of either low PAPP-A or high TSH yielded the highest sensitivity (21.1%) with a specificity of 85.7%. Combining both markers showed an increased association (adjusted OR 9.07 [95% CI 3.34 - 24.6]) at the expense of a significant reduction in sensitivity (7.8%).

CONCLUSIONS

First-trimester low PAPP-A is associated with LBW at delivery. Neither of these biomarkers or their combination are acceptable predictors to be clinically useful tools for LBW.

Cardiac Biomarkers and Cardiovascular Outcome in Children with Chronic Kidney Disease

INTRODUCTION

Myocardial dysfunction is a leading cause of mortality in chronic kidney disease (CKD) children specially those on regular hemodialysis. Cardiac biomarkers play a key role for early detection of myocardial injury. We aim to clarify the prognostic role of circulating cardiac biomarkers, heart type fatty acid binding protein (H-FABP) and pregnancy associated plasma protein-A (PAPP-A) in CKD children on regular hemodialysis.

MATERIAL AND METHODS

This is a prospective case control study over 2 years duration. Initial assessment included 20 CKD children on regular hemodialysis and 20 age- and sex- matched healthy children as a control group. Serum level of H-FABP and PAPP-A were measured and correlated to conventional echocardiographic findings and cardiovascular outcome in CKD children.

RESULTS

60% of CKD children developed cardiovascular comorbidities. H-FABP and PAPP-A levels were significantly elevated especially in those with worse cardiovascular outcome. H-FABP and PASP-A levels were positively correlated with LVM index. At cut off point > 17.65 pg/mL, H-FABP has 91% sensitivity and 87.5% specificity for prediction of cardiac morbidity. Elevated H-FABP (OR = 33; CI 95%: 2.455 - 443.591), LVM indexed to body surface area (OR = 21; CI 95%: 1.777 - 248.103), LVM indexed to lean body mass (OR = 15; CI 95%: 1.652 -136.172), elevated PAPP-A (OR = 9.8; CI 95%: 0.898 - 106.845) and Hypertension (OR = 8.333; CI 95%: 1.034 - 67.142) are the main risk factors for cardiac morbidities in CKD children.

CONCLUSIONS

Elevated H-FABP and PAPP-A are valuable prognostic markers for cardiovascular outcome in CKD children on regular hemodialysis.

Serum Levels of Activins, Follistatins, and Growth Factors in Neoplasms of the Breast: A Case-Control Study

CONTEXT

Breast cancer is the most common malignancy in women. Noninvasive biomarkers are needed for its early diagnosis and/or prognosis.

OBJECTIVE

The aim of this case-control study was the comparison of serum activins, follistatins, and members of the IGF family levels in women with benign vs malignant breast neoplasms vs apparently healthy controls.

DESIGN AND PATIENTS

Women with breast benign (n = 100) or malignant tumors (n = 145) and disease-free controls (n = 100) were recruited. Women with breast cancer were subsequently subdivided into recently diagnosed/treatment-naive (n = 112) and chemotherapy-treated (n = 33). Anthropometric, demographic, biochemical, and histological data were recorded.

SETTING

A breast cancer clinic in Thessaloniki, Greece.

MAIN OUTCOME MEASURES

Serum levels of activin A, activin B, follistatin, follistatin-like (FSTL)-3, total IGF-1, total and intact insulin-like growth factor binding protein (IGFBP)-4 and pregnancy-associated plasma protein-A (PAPP-A) were measured with highly specific ELISA kits.

RESULTS

In adjusted comparisons, substantial differences in FSTL-3, total and intact IGFBP-4, PAPP-A, and total IGF-1 were observed between groups. In logistic regression analysis, primarily total IGFBP-4 levels were independently associated with the overall presence of breast malignancy. FSTL-3 was the only variable that could distinguish between a benign vs malignant breast mass. In linear regression analysis, FSTL-3 was independently associated with tumor size.

CONCLUSIONS

We showed that members of the IGF-1/IGFBP-4/PAPP-A axis and FSTL-3 may serve as surrogate markers in breast cancer. Future mechanistic and longitudinal studies and/or clinical trials are needed to explore the efficacy of these molecules as noninvasive biomarkers and their possible therapeutic potential in breast cancer.

Trisomy 21 screening based on first and second trimester in a Taiwanese population

OBJECTIVE

This study investigates the performance of first- and second-trimester screening tests for detecting fetal trisomy 21 in a Taiwanese population.

MATERIALS AND METHODS

This multicenter study 29,137 cases enrolled the chromosomal abnormality screening between 2013 and 2014 two years period from Taipei city. There were 23,990 was done the first trimester screening using a combination of fetal nuchal translucency, maternal serum β-human chorionic gonadotropin, and pregnancy-associated plasma protein-A between 11⁺⁰ and 13⁺⁶ weeks of gestation age. Second-trimester screening was done for 5149 cases using a double test (β-human chorionic gonadotropin and serum alpha fetoprotein) between 15 and 20 weeks of gestation. The cut-off risk for both is 1:270 or higher.

RESULTS

This multicenter study 29,137 cases that completed first- and second-trimester screening, and the outcome was available in 28,726 cases. The mean maternal age of the screen-positive group was 34.6 ± 4.2 years. The first-trimester had 891 cases screening positive with a detection rate of 97.5% for fetal trisomy 21, and false positive rate of 3.5%. In the second-trimester had 334 cases screening positive, the detection rate and false positive rate were 33.3% and 6.4% for trisomy 21, respectively.

CONCLUSION

The first-trimester screening had higher performance with a lower false positive rate than the second-trimester screening. First-trimester screening could reduce the rate of unnecessary invasive testing for all pregnant women.

Maternal Serum PLGF, PAPPA, β-hCG and AFP Levels in Early Second Trimester as Predictors of Preeclampsia

BACKGROUND

Identifying women at risk of preeclampsia (PE) by maternal serum screening is conducive to prompt gestational management and thereby improve both maternal and perinatal outcomes. The purpose of the present study was to evaluate the association between the concentrations of maternal serum placental growth factor (PLGF), pregnancy associated plasma protein-A (PAPPA), free β-human chorionic gonadotropin (β-hCG), and αFetoprotein (AFP) and the development of preeclampsia early in the second trimester.

METHODS

Forty pregnant women subsequently developed mild PE, 21 pregnant women subsequently developed severe PE, and 61 cases of normotensive controls were included. Maternal serum concentrations of PLGF, PAPPA, β-hCG, and AFP were measured at 15 - 20 weeks of gestation.

RESULTS

Serum PLGF level was lower in women who subsequently developed PE than in normotensive controls. However, the significant difference was only found between the severe PE and control groups (p = 0.015). Serum PAPPA, β-hCG, and AFP levels were not significantly different between the PE and control groups.

CONCLUSIONS

Serum PLGF level was lower in women who subsequently developed severe PE early in the second trimester, suggesting its role in prediction of PE.

Prenatal diagnostic testing and atypical chromosome abnormalities following combined first-trimester screening: implications for contingent models of non-invasive prenatal testing

OBJECTIVES

To investigate by means of a population-based analysis of a cohort of women who underwent combined first-trimester screening (CFTS), changes in uptake of invasive prenatal diagnosis according to risk of trisomy 21 (T21) on CFTS, and prevalence and methods for ascertainment of atypical chromosome abnormalities.

METHODS

This was a retrospective cohort study using state-wide prenatal datasets from Victoria, Australia. A three-step approach was taken to analyze the data: (1) linkage of records between serum screening and diagnostic results; (2) comparison of rates of diagnostic testing according to CFTS T21 risk result category in a 2014-2015 cohort with those of a historical 2002-2004 cohort; (3) detailed analysis of atypical abnormalities in the 2014-2015 group according to CFTS T21 risk result, individual serum analyte level and other indications for invasive diagnostic testing.

RESULTS

In 2014-2015, there were 100 418 CFTS results issued for 146 776 births (68.4%). The overall prevalence of atypical chromosome abnormalities in the entire CFTS cohort was 0.10% and was highest in those with CFTS T21 risk > 1 in 10 (4.6%), or serum analyte levels < 0.2 multiples of the median (MoM) (6.9% for pregnancy-associated plasma protein-A (PAPP-A) and 5.2% for beta-human chorionic gonadotropin (β-hCG)). Almost half (49.2%) of women with PAPP-A < 0.2 MoM had a risk for T21 on CFTS of less than 1 in 100. The majority (55%) of atypical abnormalities occurred in women with CFTS T21 risk below 1 in 300, and were most commonly detected on ultrasound examination (47.1%).

CONCLUSION

Concerns regarding missed diagnoses of atypical chromosome abnormalities when non-invasive prenatal testing is offered after a result of high risk on CFTS can be mitigated if invasive diagnostic testing is offered to those women with CFTS T21 risk of > 1 in 100, serum PAPP-A or β-hCG < 0.2 MoM, or ultrasound-detected abnormality. This has implications for contingent models of screening. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

First-trimester screening for early and late preeclampsia using maternal characteristics, biomarkers, and estimated placental volume

BACKGROUND

Preeclampsia is a major cause of perinatal morbidity and mortality. First-trimester screening has been shown to be effective in selecting patients at an increased risk for preeclampsia in some studies.

OBJECTIVE

We sought to evaluate the feasibility of screening for preeclampsia in the first trimester based on maternal characteristics, medical history, biomarkers, and placental volume.

STUDY DESIGN

This is a prospective observational nonintervention cohort study in an unselected US population. Patients who presented for an ultrasound examination between 11-13+6 weeks' gestation were included. The following parameters were assessed and were used to calculate the risk of preeclampsia: maternal characteristics (demographic, anthropometric, and medical history), maternal biomarkers (mean arterial pressure, uterine artery pulsatility index, placental growth factor, pregnancy-associated plasma protein A, and maternal serum alpha-fetoprotein), and estimated placental volume. After delivery, medical records were searched for the diagnosis of preeclampsia. Detection rates for early-onset preeclampsia (<34 weeks' gestation) and later-onset preeclampsia (≥34 weeks' gestation) for 5% and 10% false-positive rates using various combinations of markers were calculated.

RESULTS

We screened 1288 patients of whom 1068 (82.99%) were available for analysis. In all, 46 (4.3%) developed preeclampsia, with 13 (1.22%) having early-onset preeclampsia and 33 (3.09%) having late-onset preeclampsia. Using maternal characteristics, serum biomarkers, and uterine artery pulsatility index, the detection rate of early-onset preeclampsia for either 5% or 10% false-positive rate was 85%. With the same protocol, the detection rates for preeclampsia with delivery <37 weeks were 52% and 60% for 5% and 10% false-positive rates, respectively. Based on maternal characteristics, the detection rates for late-onset preeclampsia were 15% and 48% for 5% and 10%, while for preeclampsia at ≥37 weeks' gestation the detection rates were 24% and 43%, respectively. The detection rates for late-onset preeclampsia and preeclampsia with delivery at >37 weeks' gestation were not improved by the addition of biomarkers.

CONCLUSION

Screening for preeclampsia at 11-13+6 weeks' gestation using maternal characteristics and biomarkers is associated with a high detection rate for a low false-positive rate. Screening for late-onset preeclampsia yields a much poorer performance. In this study the utility of estimated placental volume and mean arterial pressure was limited but larger studies are needed to ultimately determine the effectiveness of these markers.

Long term influence of regular intake of high dose n-3 fatty acids on CD40-ligand, pregnancy-associated plasma protein A and matrix metalloproteinase-9 following acute myocardial infarction

Pregnancy-associated plasma protein A (PAPP-A) and matrix metalloproteinase 9 (MMP-9), both zinc-binding endopeptidases, are abundantly expressed in ruptured and eroded plaques in patients with acute coronary syndromes (ACS).The adhesion molecule CD-40 ligand (CD40L), expressed on activated platelets and T-lymphocytes, can activate metalloproteinases and thereby promote plaque-rupture. N-3 fatty acids, through their anti-inflammatory and anti-thrombotic properties,might reduce the levels of these proatherosclerotic markers and thereby the development of ACS. 300 patients were randomized on day4 to 6 following an acute myocardial infarction (MI) to receive either 4g of n-3 fatty acids or a similar daily dose of corn oil for at least one year.We compared levels of PAPP-A, MMP-9 and sCD-40 L at baseline and 12 months in each group, and also looked for inter-group changes. In the omega-3 group, the median level of PAPP-A rose from 0.47 mU/l to 0.56 mU/l (p < 0.001). In the same group, sCD-40 L decreased froma mean baseline value of 5.19 ng/ml to 2.45 ng/ml (p < 0.001) and MMP-9 decreased nonsignificantly from 360.50 ng/ml to 308.00 ng/ml. Corresponding values for the corn oil group were 0.54 mU/l to 0.59 mU/l for PAPP-A (p= 0.007), 5.27 ng/ml to 2.84 ng/ml for sCD-40 L (p< 0.001) and 430.00 ng/ml to 324.00 ng/ml for MMP-9 (p=ns), respectively. In conclusion; both interventions resulted in a significant rise in PAPP-A, a significant decrease in sCD40L and a non-significant decrease in MMP-9 after 12 months of treatment in MI survivors. No inter-group differences were noted.

Competing-risks model in screening for pre-eclampsia in twin pregnancy according to maternal factors and biomarkers at 11-13 weeks' gestation

OBJECTIVE

To develop a model for screening for pre-eclampsia (PE) in twin pregnancies based on maternal demographic characteristics and medical history and biomarkers at 11-13 weeks' gestation.

METHODS

This was a screening study in twin pregnancies at 11-13 weeks' gestation. Bayes theorem was used to combine the a-priori risk from maternal factors with various combinations of uterine artery pulsatility index (UtA-PI), mean arterial pressure (MAP), serum pregnancy-associated plasma protein-A (PAPP-A) and placental growth factor (PlGF) multiples of the median (MoM) values. The performance of screening for PE requiring delivery at < 32, < 37 and < 42 weeks' gestation was estimated in 1100 twin pregnancies and 35 948 singleton pregnancies with complete data on UtA-PI, MAP, PlGF and PAPP-A.

RESULTS

In twin pregnancies that developed PE, the values of MAP and UtA-PI were increased and the values of PlGF and PAPP-A were decreased. The distributions of log₁₀ MoM values of biomarkers with gestational age at delivery were similar to those that were previously reported in singleton pregnancies and it was therefore assumed that the same model could be used for both singleton and twin pregnancies. The performance of screening for PE by maternal factors was improved by the addition of MAP, UtA-PI and PlGF; there was no further improvement with the addition of PAPP-A. In a mixed population of singleton and twin pregnancies, combined screening by maternal factors, MAP, UtA-PI and PlGF and risk cut-off of 1 in 75 for PE at < 37 weeks, the detection rate of PE at < 32, < 37 and < 42 weeks in singleton pregnancies was 91%, 77% and 57%, respectively, at a screen-positive rate (SPR) of 13%; the respective rates for twin pregnancies were 100%, 99% and 97%, at a SPR of 75%.

CONCLUSION

First-trimester combined screening for PE in singleton pregnancies can be adapted for screening in twins, leading to detection of nearly all affected cases but at a high SPR. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Physiological parameters regulating circulating levels of the IGFBP-4/Stanniocalcin-2/PAPP-A axis

BACKGROUND

Insulin Growth Factor Binding Protein 4 (IGFBP-4), Stanniocalcin-2 (STC-2) and Pregnancy-Associated Plasma Protein-A (PAPP-A) have a well-documented involvement in several physiological functions in humans but predictors of their circulating levels remain largely unknown. We aimed to identify anthropometric and biochemical parameters associated with circulating levels of IGFBP-4/STC-2/PAPP-A axis (ISPa) cross-sectionally and to study their day-night variation and their regulation in response to mixed meal and exercise.

METHODS

One hundred twenty two healthy individuals were evaluated cross-sectionally. Subgroups were subjected to standardized mixed meal ingestion in increasing quantities of 125mL or 250mL, or aerobic exercise for 30min, or day-night rhythm study. Main outcome measurements were circulating IGFBP-4 (total and intact), STC-2 and PAPP-A levels.

RESULTS

In multivariate models, the main predictors of serum total IGFBP-4 were PAPP-A and female gender. Intact IGFBP-4 was positively associated with serum creatinine. Height was inversely and female gender and % of total body fat were positively correlated with STC-2. PAPP-A decreased after ingesting both the 125mL (p=0.03) and 250mL quantities (p=0.001), while total IGFBP-4 was reduced after the 250mL quantity (p=0.001). Exercise increased STC-2 and PAPP-A levels (p<0.001 for both). Intact, and to a lesser extent total, IGFBP-4 displayed a cortisol-like day/night variation.

CONCLUSIONS

We report for the first time anthropometric and physiological modulators of ISPa serum levels in healthy humans.

External Quality Assessment of First-Trimester Prenatal Biochemical Screening in China

BACKGROUND

Free β subunit of human chorionic gonadotropin (free β-hCG) and pregnancy-associated plasma protein A (PAPP-A) are two important biomarkers in first-trimester prenatal screening. This study intended to reflect their analytical performance in clinical laboratories and main platforms of the 2015 External Quality Assessment (EQA) scheme for the first-trimester biochemical screening in China.

METHODS

Ten lyophilized EQA samples, divided into two sets and analyzed in two cycles 20151 and 20152, were distributed to each participant in 2015. Satisfactory performance was defined as scores more than 80 of acceptable results within the evaluation criterion of ± 30%. The robust coefficient of variability (CV) of each sample was calculated by analytes and mainstream platforms. The chi-square (2) test and the Mann-Whitney test were respectively used to compare the acceptable performance and the robust CV between two analytes, as well as two mainstream platforms.

RESULTS

A total of 142 laboratories were enrolled in this EQA scheme. For free β-hCG and PAPP-A, the number of effective results were 1330 and 1355, respectively, and the overall acceptable rates of results were 95.11% and 92.32%, respectively. For cycle 20151 and 20152, the acceptable rates were respectively 92.59% and 96.19% for free β-hCG and 89.78% and 94.78% for PAPP-A. The 2 test showed acceptable performance differed significantly between the two analytes, as well as two platforms for PAPP-A. Significant difference of the robust CV in different analytes and platforms was demonstrated by Mann-Whitney test.

CONCLUSIONS

Greater than 92% of results were acceptable. However, continuous improvement and further research of this EQA scheme is in process.

First trimester ultrasound tests alone or in combination with 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.Non-invasive 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.Before agreeing to screening tests, parents need to be fully informed about the risks, benefits and possible consequences of such a test. This includes subsequent choices for further tests they may face, and the implications of both false positive and false negative screening tests (i.e. invasive diagnostic testing, and the possibility that a miscarried fetus may be chromosomally normal). The decisions that may be faced by expectant parents inevitably engender a high level of anxiety at all stages of the screening process, and the outcomes of screening can be associated with considerable physical and psychological morbidity. No screening test can predict the severity of problems a person with Down's syndrome will have.

OBJECTIVES

To estimate and compare the accuracy of first trimester ultrasound markers alone, and in combination with first trimester serum tests for the detection of Down's syndrome.

SEARCH METHODS

We carried out extensive literature searches including 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), and The Database of Abstracts of Reviews of Effects (the Cochrane Library 2011, Issue 7). We checked reference lists and published review articles for additional potentially relevant studies.

SELECTION CRITERIA

Studies evaluating tests of first trimester ultrasound screening, alone or in combination with first trimester serum tests (up to 14 weeks' gestation) for Down's syndrome, compared with a reference standard, either chromosomal verification or macroscopic postnatal inspection.

DATA COLLECTION AND ANALYSIS

Data were extracted as test positive/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 criteria. We used hierarchical summary ROC meta-analytical methods to analyse test performance and compare test accuracy. Analysis of studies allowing direct comparison between tests was undertaken. We investigated the impact of maternal age on test performance in subgroup analyses.

MAIN RESULTS

We included 126 studies (152 publications) involving 1,604,040 fetuses (including 8454 Down's syndrome cases). Studies were generally good quality, although differential verification was common with invasive testing of only high-risk pregnancies. Sixty test combinations were evaluated formed from combinations of 11 different ultrasound markers (nuchal translucency (NT), nasal bone, ductus venosus Doppler, maxillary bone length, fetal heart rate, aberrant right subclavian artery, frontomaxillary facial angle, presence of mitral gap, tricuspid regurgitation, tricuspid blood flow and iliac angle 90 degrees); 12 serum tests (inhibin A, alpha-fetoprotein (AFP), free beta human chorionic gonadotrophin (ßhCG), total hCG, pregnancy-associated plasma protein A (PAPP-A), unconjugated oestriol (uE3), disintegrin and metalloprotease 12 (ADAM 12), placental growth factor (PlGF), placental growth hormone (PGH), invasive trophoblast antigen (ITA) (synonymous with hyperglycosylated hCG), growth hormone binding protein (GHBP) and placental protein 13 (PP13)); and maternal age. The most frequently evaluated serum markers in combination with ultrasound markers were PAPP-A and free ßhCG.Comparisons of the 10 most frequently evaluated test strategies showed that a combined NT, PAPP-A, free ßhCG and maternal age test strategy significantly outperformed ultrasound markers alone (with or without maternal age) except nasal bone, detecting about nine out of every 10 Down's syndrome pregnancies at a 5% false positive rate (FPR). In both direct and indirect comparisons, the combined NT, PAPP-A, free ßhCG and maternal age test strategy showed superior diagnostic accuracy to an NT and maternal age test strategy (P < 0.0001). Based on the indirect comparison of all available studies for the two tests, the sensitivity (95% confidence interval) estimated at a 5% FPR for the combined NT, PAPP-A, free ßhCG and maternal age test strategy (69 studies; 1,173,853 fetuses including 6010 with Down's syndrome) was 87% (86 to 89) and for the NT and maternal age test strategy (50 studies; 530,874 fetuses including 2701 Down's syndrome pregnancies) was 71% (66 to 75). Combinations of NT with other ultrasound markers, PAPP-A and free ßhCG were evaluated in one or two studies and showed sensitivities of more than 90% and specificities of more than 95%.High-risk populations (defined before screening was done, mainly due to advanced maternal age of 35 years or more, or previous pregnancies affected with Down's syndrome) showed lower detection rates compared to routine screening populations at a 5% FPR. Women who miscarried in the over 35 group were more likely to have been offered an invasive test to verify a negative screening results, whereas those under 35 were usually not offered invasive testing for a negative screening result. Pregnancy loss in women under 35 therefore leads to under-ascertainment of screening results, potentially missing a proportion of affected pregnancies and affecting test sensitivity. Conversely, for the NT, PAPP-A, free ßhCG and maternal age test strategy, detection rates and false positive rates increased with maternal age in the five studies that provided data separately for the subset of women aged 35 years or more.

AUTHORS' CONCLUSIONS

Test strategies that combine ultrasound markers with serum markers, especially PAPP-A and free ßhCG, and maternal age were significantly better than those involving only ultrasound markers (with or without maternal age) except nasal bone. They detect about nine out of 10 Down's affected pregnancies for a fixed 5% FPR. Although the absence of nasal bone appeared to have a high diagnostic accuracy, only five out of 10 affected Down's pregnancies were detected at a 1% FPR.

First and second trimester serum tests with and without first trimester ultrasound tests for Down's syndrome screening

BACKGROUND

Down's syndrome occurs when a person has three copies of chromosome 21 (or the specific area of chromosome 21 implicated in causing Down's syndrome) rather than two. It is the commonest congenital cause of mental disability. Non-invasive 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.  Before agreeing to screening tests, parents need to be fully informed about the risks, benefits and possible consequences of such a test. This includes subsequent choices for further tests they may face, and the implications of both false positive (i.e. invasive diagnostic testing, and the possibility that a miscarried fetus may be chromosomally normal) and false negative screening tests (i.e. a fetus with Down's syndrome will be missed). The decisions that may be faced by expectant parents inevitably engender a high level of anxiety at all stages of the screening process, and the outcomes of screening can be associated with considerable physical and psychological morbidity. No screening test can predict the severity of problems a person with Down's syndrome will have.

OBJECTIVES

To estimate and compare the accuracy of first and second trimester serum markers with and without first trimester ultrasound markers for the detection of Down's syndrome in the antenatal period, as combinations of markers.

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), and Health Services Research Projects in Progress database (25 August 2011). We did not apply a diagnostic test search filter. We did forward citation searching in ISI citation indices, Google Scholar and PubMed 'related articles'. We also searched reference lists of retrieved articles SELECTION CRITERIA: Studies evaluating tests of combining first and second trimester maternal serum markers in women up to 24 weeks of gestation for Down's syndrome, with or without first trimester ultrasound markers, compared with a reference standard, either chromosomal verification or macroscopic postnatal inspection.

DATA COLLECTION AND ANALYSIS

Data were extracted as test positive/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 criteria. We used hierarchical summary ROC meta-analytical methods to analyse test performance and compare test accuracy. Analysis of studies allowing direct comparison between tests was undertaken. We investigated the impact of maternal age on test performance in subgroup analyses.

MAIN RESULTS

Twenty-two studies (reported in 25 publications) involving 228,615 pregnancies (including 1067 with Down's syndrome) were included. Studies were generally high quality, although differential verification was common with invasive testing of only high risk pregnancies. Ten studies made direct comparisons between tests. Thirty-two different test combinations were evaluated formed from combinations of eight different tests and maternal age; first trimester nuchal translucency (NT) and the serum markers AFP, uE3, total hCG, free βhCG, Inhibin A, PAPP-A and ADAM 12. We looked at tests combining first and second trimester markers with or without ultrasound as complete tests, and we also examined stepwise and contingent strategies.Meta-analysis of the six most frequently evaluated test combinations showed that a test strategy involving maternal age and a combination of first trimester NT and PAPP-A, and second trimester total hCG, uE3, AFP and Inhibin A significantly outperformed other test combinations that involved only one serum marker or NT in the first trimester, detecting about nine out of every 10 Down's syndrome pregnancies at a 5% false positive rate. However, the evidence was limited in terms of the number of studies evaluating this strategy, and we therefore cannot recommend one single screening strategy.

AUTHORS' CONCLUSIONS

Tests involving first trimester ultrasound with first and second trimester serum markers in combination with maternal age are significantly better than those without ultrasound, or those evaluating first trimester ultrasound in combination with second trimester serum markers, without first trimester serum markers. We cannot make recommendations about a specific strategy on the basis of the small number of studies available.

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.

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.