Association of first-trimester angiogenic factors with placental histological findings in late-onset preeclampsia

Maternal, reproductive and perinatal factors and the risks of birth defects: traditional and emerging factors

RESEARCH QUESTION

Does an association exist between maternal, reproductive and perinatal factors, and the risks of major non-chromosomal birth defects?

DESIGN

This population-based cohort study included 1,126,058 naturally conceived singleton live births (21,644 with and 1,104,414 without a major non-chromosomal defect) who were born between 2004 and 2018 in New York, Texas, Massachusetts and North Carolina. All study children were linked to their respective state birth defect registries to identify major birth defects diagnosed within the first year of life, and to state death records. Children with chromosomal defects were excluded. Genitourinary defects were only evaluated in boys. Placental and bleeding issues included placenta previa, placental abruption, uterine bleeding and other excessive bleeding, and, at delivery, blood transfusion or unplanned hysterectomy. Adjusted odds ratios and 95% confidence intervals were modelled using logistic regression.

RESULTS

Among major non-chromosomal defects, the highest significant risks were with pre-gestational diabetes (adjusted OR 2.48, 95% CI 2.25 to 2.74), followed by placental or bleeding issues (adjusted OR 1.82, 95% CI 1.66 to 1.99); this pattern was also evident for congenital heart defects, blastogenesis defects, orofacial defects, gastrointestinal defects and musculoskeletal defects. Hypertension (pre-gestational and gestational), prior caesarean delivery, older maternal age and higher body mass index were also significant risk factors.

CONCLUSIONS

The risk factors most strongly associated with major non-chromosomal birth defects were pre-gestational diabetes and placental or bleeding issues; other significantly increased risks were hypertension (pre-gestational and gestational), prior caesarean delivery, older maternal age and pre-pregnancy body mass index 30 kg/m2 or above.

Early Fetal Growth Restriction with or Without Hypertensive Disorders: a Clinical Overview

Early onset fetal growth restriction (FGR) is one of the main adverse pregnancy conditions, often associated with poor neonatal outcomes. Frequently, early onset FGR is associated with early onset hypertensive disorders of pregnancy (HDP), and in particular preeclampsia (PE). However, to date, it is still an open question whether pregnancies complicated by early FGR plus HDP (FGR-HDP) and those complicated by early onset FGR without HDP (normotensive-FGR (n-FGR)) show different prenatal and postnatal outcomes and, consequently, should benefit from different management and long-term follow-up. Recent data support the hypothesis that the presence of PE may have an additional impact on maternal hemodynamic impairment and placental lesions, increasing the risk of poor neonatal outcomes in pregnancy affected by early onset FGR-HDP compared to pregnancy affected by early onset n-FGR. This review aims to elucidate this poor studied topic, comparing the clinical characteristics, perinatal outcomes, and potential long-term sequelae of early onset FGR-HDP and early onset n-FGR.

Hemodynamic pathways of gestational hypertension and preeclampsia

Gestational hypertension and preeclampsia are the 2 main types of hypertensive disorders in pregnancy. Noninvasive maternal cardiovascular function assessment, which helps obtain information from all the components of circulation, has shown that venous hemodynamic dysfunction is a feature of preeclampsia but not of gestational hypertension. Venous congestion is a known cause of organ dysfunction, but its potential role in the pathophysiology of preeclampsia is currently poorly investigated. Body water volume expansion occurs in both gestational hypertension and preeclampsia, and this is associated with the common feature of new-onset hypertension after 20 weeks of gestation. Blood pressure, by definition, is the product of intravascular volume load and vascular resistance (Ohm's law). Fundamentally, hypertension may present as a spectrum of cardiovascular states varying between 2 extremes: one with a predominance of raised cardiac output and the other with a predominance of increased total peripheral resistance. In clinical practice, however, this bipolar nature of hypertension is rarely considered, despite the important implications for screening, prevention, management, and monitoring of disease. This review summarizes the evidence of type-specific hemodynamic profiles in the latent and clinical stages of hypertensive disorders in pregnancy. Gestational volume expansion superimposed on an early gestational closed circulatory circuit in a pressure- or volume-overloaded condition predisposes a patient to the gradual deterioration of overall circulatory function, finally presenting as gestational hypertension or preeclampsia-the latter when venous dysfunction is involved. The eventual phenotype of hypertensive disorder is already predictable from early gestation onward, on the condition of including information from all the major components of circulation into the maternal cardiovascular assessment: the heart, central and peripheral arteries, conductive and capacitance veins, and body water content. The relevance of this approach, outlined in this review, openly invites for more in-depth research into the fundamental hemodynamics of gestational hypertensive disorders, not only from the perspective of the physiologist or the scientist, but also in assistance of clinicians toward understanding and managing effectively these severe complications of pregnancy.

Association of mid-trimester maternal angiogenic biomarkers with small-for-gestational-age infants in an urban Zambian cohort: a nested case-control study

Objective

To investigate whether angiogenic biomarker concentrations differ between women who deliver small‐for‐gestational‐age (SGA) infants (<10th centile birth weight for gestational age) compared with controls, because identifying SGA risk early could improve outcomes.

Methods

This case‐control study compared serum concentrations of angiogenic biomarkers before 24 weeks of pregnancy from 62 women who delivered SGA infants (cases) and 62 control women from an urban Zambian cohort. Odds of delivering an SGA infant were calculated using conditional logistic regression.

Results

Placental growth factor (PlGF), soluble fms‐like tyrosine kinase (sFLT‐1) and soluble endoglin (sEng) in controls were 37.74 pg/mL (interquartile range [IQR] 23.12–63.15), 2525.18 pg/mL (IQR 1502.21–4265.54) and 2408.18 pg/mL (IQR 1854.87–3017.94), respectively. SGA cases had higher PlGF (40.50 pg/mL, IQR 22.81–67.94) and sFLT‐1 (2613.06 pg/mL, IQR 1720.58–3722.50), and lower sEng (2038.06 pg/mL, IQR 1445.25–3372.26). Participants with sEng concentration below and concomitant sFLT‐1 concentration above their respective thresholds (n = 40) had five‐fold higher odds of SGA (adjusted odds ratio 4.77, 95% confidence interval 1.61–14.1; P = 0.005).

Conclusion

Biomarker concentrations were similar between cases and controls. Participants with concomitant low sEng and high sFLT‐1 had the highest odds of SGA, suggesting that a combination of biomarkers may better for predicting SGA than single biomarkers.

Prediction of SGA risk using the interaction of multiple angiogenic biomarkers may perform better than using a single angiogenic biomarker concentration before 24 weeks gestation.

The association between maternal placental growth factor and placental maternal vascular malperfusion lesions

INTRODUCTION

Placental Growth Factor (PlGF) is used for the prediction of preeclampsia (PE), a syndrome associated with maternal vascular malperfusion (MVM). Our goal is to determine the correlation between PlGF and MVM.

MATERIAL AND METHODS

We performed a secondary analysis of the PEARL study that included nulliparous women with PE (cases), and low-risk nulliparous women recruited in early pregnancy (controls). All participants provided blood samples at diagnosis of PE (cases), or between 26 and 34 weeks (controls) for measurement of PlGF (B·R·A·H·M·S plus KRYPTOR automated assays), that was transformed into multiple of median (MoM). Placental examination was performed for the diagnosis of MVM based on the Amsterdam Placental Workshop Group Consensus Statement. Nonparametric tests and receiver operating characteristic (ROC) curves were used to compare PlGF in pregnancies with, and without PE, stratified by the presence of MVM.

RESULTS

Third trimester PlGF was lower in PE cases with MVM (N = 20; median: 0.04 MoM; interquartile: 0.03-0.09; p<0.0001), and in controls with MVM (N = 4; 0.30MoM; 0.07-0.52; p = 0.002) compared to controls without MVM (N = 29; 0.99 MoM; 0.67-1.52). PlGF in PE cases without MVM (N = 5; 0.18 MoM; 0.17-1.64) was not significantly different than in controls without MVM but the sample size was small. ROC curve demonstrated a greater predictability of PlGF for PE with MVM than PE without MVM (AUC: 0.99 vs. 0.38; p<0.0001).

DISCUSSION

Third trimester PlGF is a better predictor of PE associated with MVM than a predictor of PE without MVM. We hypothesize that PlGF is a stronger marker of MVM than PE.

Second Trimester Placental Growth Factor Levels and Placental Histopathology in Low-Risk Nulliparous Pregnancies

OBJECTIVE

Placental growth factor (PlGF) levels are lower at delivery in pregnancies with preeclampsia or fetuses small for gestational age (SGA). These obstetrical complications are typically mediated by placental dysfunction, most commonly related to the specific placental phenotype termed placental maternal vascular malperfusion (MVM). The objective of this study was to determine the relationship between PlGF levels in the second trimester and the development of placental diseases that underlie adverse perinatal outcomes.

METHODS

We performed a secondary analysis of the prospective Placental Health Study in unselected healthy nulliparous women (n = 773). Maternal demographic data, Doppler ultrasound measurements, and plasma PlGF levels at 15 to 18 weeks gestation were analyzed for association with pregnancy outcomes and placental pathology following delivery.

RESULTS

Low PlGF levels in the second trimester (<10th percentile; <72 pg/mL) was associated with preterm delivery (<37 weeks; 26% vs. 6%, P < 0.001; unadjusted odds ratio (OR) 5.75, 95% CI 3.2-10.5), reduced mean birthweight (2998 vs. 3320 g, P < 0.001), SGA deliveries (25% vs. 11%, P = 0.001; OR 2.6, 95% CI 1.5-4.6), and preeclampsia (7% vs. 2%, P = 0.02; OR 4.3, 95% CI 1.5-12.8) relative to normal PlGF levels (≥10th percentile; ≥72 pg/mL). Low PlGF was associated with lower mean placental weight (447 vs. 471 g, P = 0.01), aberrant cord insertion (25% vs. 12%, P = 0.001) and a pathologic diagnosis of MVM (18% vs. 11%, P = 0.04; OR 1.9, 95% CI 1.01-3.55) but not with other placental pathologies.

CONCLUSION

MVM placental pathology and related adverse perinatal outcomes are associated with low PlGF in the early second trimester for healthy nulliparous women.

The Maternal-Fetal Interface in Small-for-Gestational-Age Pregnancies Is Associated With a Reduced Quantity of Human Decidual NK Cells With Weaker Functional Ability

Small for gestational age (SGA) refers to a birth weight that is less than the 10th percentile of the mean weight of infants at the same gestational age. This condition is associated with a variety of complications, and a high risk of cardiovascular and cerebrovascular diseases in adulthood. Decidual natural killer (dNK) cells at the maternal–fetal interface have received significant research attention in terms of normal pregnancy or miscarriage; however, data relating to SGA are limited. In this study, we aimed to investigate the characteristics and regulatory role of dNK cells at the maternal–fetal interface in SGA. Using immunofluorescence assays, we found that dNK cells maintained close contact with extra-villous trophoblasts, and the proportion of dNK cells in SGA decreased more than in appropriate for gestational age (AGA). Flow cytometry also showed that there was a significantly lower percentage of dNK cells in SGA (25.01 ± 2.43%) than in AGA (34.25 ± 2.30%) (p = 0.0103). The expression of the inhibitory receptor NKG2A on dNK cells and the secretion levels of both perforin and TGF-β1 from dNK cells were significantly higher in SGA than in AGA, while the cytotoxicity of dNK cells in SGA against K562 cells was attenuated. Compared to AGA, the functional ability of dNK cells in SGA showed significant functional impairment in promoting proliferation, migration, invasion, and tube formation in trophoblast cells or vascular endothelial cells. The abnormal function of dNK cells may affect fetal growth and development, and could therefore participate in the pathogenesis of SGA.

Levels of angiogenic markers in second-trimester maternal serum from in vitro fertilization pregnancies with oocyte donation

OBJECTIVE

To determine whether differences exist in angiogenic placental growth factor (PlGF) and antiangiogenic soluble vascular endothelial growth factor receptor 1 (sVEGFR-1; both being early markers of placental ischemic disease) in oocyte-donation (OD) pregnancies, compared with autologous in vitro fertilization (aIVF) and spontaneous pregnancies.

DESIGN

Case-control study of residual second-trimester serum samples from women undergoing prenatal screening.

SETTING

Academic medical center.

PATIENT(S)

Fifty-seven OD pregnancies were identified. Each OD pregnancy was matched to two spontaneous pregnancies (n = 114) and one aIVF pregnancy (n = 57).

INTERVENTIONS(S)

None.

MAIN OUTCOME MEASURE(S)

Second-trimester serum PlGF and sVEGFR-1 levels.

RESULT(S)

sVEGFR-1, PlGF, and unconjugated E₂ levels were similar among the three study groups. The ratio of sVEGFR-1 to PlGF was significantly higher in the OD group. Consistently with previous studies, alpha-fetoprotein (AFP) in the OD group was significantly elevated compared with spontaneous pregnancy. Both aIVF and OD groups had greater levels of inhibin A than the spontaneous pregnancy group, and the OD group had significantly higher levels of inhibin A than the aIVF group. hCG levels were significantly elevated in aIVF compared with spontaneous pregnancy; however, levels were not different between aIVF and OD.

CONCLUSION(S)

Second-trimester serum sVEGFR-1 and PlGF levels were not significantly altered in OD pregnancies. Our data support previous findings that OD pregnancies have uniquely increased second-trimester AFP, hCG, and inhibin A levels compared with aIVF. However, the biologic basis of these marker elevations in OD may not be related to placental angiogenesis.

Correlation of biological parameters with placental parameters and pregnancy outcomes in pre-eclamptic women

INTRODUCTION

Pre-eclampsia is characterized by maternal vascular malperfusion and chronic inflammation in placenta. Our purpose was to investigate the potential correlation of biological parameters with placental parameters and pregnancy outcomes in pre-eclamptic women.

METHODS

Pre-eclamptic women were identified by interrogation of the Medical Registry Department in six French maternities between April 2013 and June 2018. Histological parameters in placentas (weight, macroscopic and microscopic lesions), baseline maternal characteristics and pregnancy outcomes (course of pregnancy, newborns' characteristics) were collected. Biological parameters were blood cell ratios (Platelet-to-Lymphocyte Ratio (PLR), Neutrophil-to-Lymphocyte Ratio (NLR)) collected at delivery and Placental growth factor (PlGF) measured in women with an available first trimester serum sample. Correlations of blood cell ratios and PlGF levels with placental parameters and pregnancy outcomes were assessed by Pearson's correlation test for quantitative parameters and by logistic regression analysis for qualitative parameters.

RESULTS

202 pregnancies were included, among which 68 had a first trimester PlGF quantification. No correlation was found between biological parameters and placental lesions. Low PLR was correlated with low placental weight (r = 0.156, p = 0.036) and with low birth weight (r = 0.179, p = 0.015). Low PlGF was correlated with long time from pre-eclampsia diagnosis to delivery (r = -0.250, p = 0.048).

CONCLUSIONS

There is no correlation between biological parameters and placental lesions in pre-eclamptic women. Yet, low PLR at delivery is correlated with low placental and birth weights. Moreover, low first trimester PlGF is correlated with long time from pre-eclampsia diagnosis to delivery.

The effect of early-onset preeclampsia on the intestinal blood flow of preterm infants

BACKGROUND

Preeclampsia is associated with important vascular maternal changes. However, its repercussions on newborns' circulation have hardly been reported.

OBJECTIVE

To investigate whether early-onset preeclampsia is associated with altered blood flow of the superior mesenteric artery (SMA) in preterm infants.

MATERIALS AND METHODS

Prospective study with 60 preterm infants of mothers with early-onset preeclampsia (PE) and 60 of normotensive mothers, paired according to the gestational age, from 2013 to 2016. Maternal, gestational, and neonatal clinical data were evaluated. The outcome of interest was the blood flow velocity in SMA, evaluated by the peak systolic velocity and end-diastolic velocity and by the resistance index and pulsatility index, through the Doppler ultrasound in the first 72 h of life. Covariance analysis was used to determine the PE effect on the SMA blood flow, controlling for possible confounding variables.

RESULTS

The mean gestational age was 30 weeks. Infants of mothers with PE had significantly lower values of peak systolic and end-diastolic velocity (57.75 ± 17.49 and 12.29 ± 5.74) compared with the control group (67.17 ± 29.57 and 15.03 ± 7.52), even after control of covariates.

CONCLUSION

Early-onset preeclampsia is associated with decreased blood flow of SMA in preterm infants on the first days of life.

First-Trimester Placental Growth Factor for the Prediction of Preeclampsia in Nulliparous Women: The Great Obstetrical Syndromes Cohort Study

BACKGROUND

First-trimester maternal serum markers have been associated with preeclampsia (PE). We aimed to evaluate the performance of first-trimester placental growth factor (PlGF) for the prediction of PE in nulliparous women.

SUBJECTS AND METHODS

We conducted a prospective cohort study of nulliparous women with singleton pregnancy at 11-13 weeks. Maternal serum PlGF concentration was measured using B·R·A·H·M·S PlGFplus KRYPTOR automated assays and reported in multiple of the median adjusted for gestational age. We used proportional hazard models, along with receiver operating characteristic curves and areas under the curve (AUC).

RESULTS

Out of 4,652 participants, we observed 232 (4.9%) cases of PE including 202 (4.3%) term and 30 (0.6%) preterm PE. PlGF was associated with the risk of term (AUC = 0.61, 95% confidence interval [CI] 0.57-0.65) and preterm PE (AUC = 0.73, 95% CI 0.64-0.83). The models were improved with the addition of maternal characteristics (AUC for term PE 0.66, 95% CI 0.62-0.71; AUC for preterm PE 0.81, 95% CI 0.72-0.91; p < 0.01). At a false-positive rate of 10%, PlGF combined with maternal characteristics could have predicted 26% of term and 55% of preterm PE. The addition of pregnancy-associated plasma protein A did not significantly improve the prediction models.

CONCLUSION

First-trimester PlGF combined with maternal characteristics is useful to predict preterm PE in nulliparous women.

Early second trimester maternal serum markers in the prediction of gestational diabetes mellitus

AIMS/INTRODUCTION

To determine whether maternal serum markers in the early second trimester are useful for prediction of gestational diabetes mellitus (GDM).

MATERIALS AND METHODS

A total of 876 singleton pregnancies were recruited in the present study. Blood samples were collected during 16-20 gestational weeks. GDM women were diagnosed by an oral glucose tolerance test during 24-28 gestational weeks. A total of 56 women with GDM and 73 healthy pregnant women were selected. Maternal serum concentrations of placental protein 13 (PP13), pentraxin 3 (PTX3), soluble fms-like tyrosine kinase-1 (sFlt-1), myostatin and follistatin (FST) were detected at 16-20 weeks' gestation. All of these markers concentrations were expressed as multiples of the medians. The Mann-Whitney U-test was used for comparison of the multiples of the medians of different concentrations of these five serum markers between the GDM group and the control group. Receiver operating characteristic curve analysis was applied to assess the sensitivity and specificity of significant serum markers from a Mann-Whitney U-test comparison.

RESULTS

Compared with healthy pregnancies, the serum levels of PP13, PTX3, sFlt-1, myostatin and FST in the early second trimester were significantly increased in patients who had developed GDM late. In screening for GDM by PP13, PTX3, sFlt-1, myostatin and FST, the detection rates were 92.3, 94.9, 94.9, 92.5 and 92.3%, respectively at 80% specificity. PTX3 and sFlt-1 were the most sensitive markers.

CONCLUSIONS

Maternal serum markers including PP13, PTX3, sFlt-1, myostatin and FST increase in the early second trimester of women with GDM. These five markers, especially PTX3 and sFlt-1, could have the value of prediction for those patients who would develop GDM in the late second trimester.

Celecoxib restores angiogenic factor expression at the maternal-fetal interface in the BPH/5 mouse model of preeclampsia

Preeclampsia (PE), a hypertensive disease of pregnancy, is a leading cause of fetal and maternal morbidity/mortality. Early angiogenic and inflammatory disturbances within the placenta are thought to underlie the development of the maternal PE syndrome and poor pregnancy outcomes. However, the exact etiology remains largely unknown. Here, we use the BPH/5 mouse model of PE to elucidate the way in which inflammation early in pregnancy contributes to abnormal expression of angiogenic factors at the maternal-fetal interface. We have previously described improvement in maternal hypertension and fetal growth restriction in this model after treatment with the anti-inflammatory cyclooxygenase-2 (Cox2) specific inhibitor celecoxib. To further characterize the mechanisms by which celecoxib improves poor pregnancy outcomes in BPH/5 mice, we determined expression of angiogenic factors and complement pathway components after celecoxib. In BPH/5 implantation sites there was increased hypoxia inducible factor-1α ( Hif1α), heme oxygenase-1 ( Ho-1), and stem cell factor ( Scf) mRNA concomitant with elevated prostaglandin synthase 2 ( Ptgs2), encoding Cox2, and elevated VEGF protein. Angiopoietin 1 ( Ang1), tunica interna endothelial cell kinase-2 receptor ( Tie2), complement factor 3 ( C3), and complement factor B ( CfB) were increased in midgestation BPH/5 placentae. Whereas BPH/5 expression levels of VEGF, Ang1, and Tie2 normalized after celecoxib, placental C3 and CfB mRNA remained unchanged. However, celecoxib did reduce the pregnancy-specific circulating soluble fms-like tyrosine kinase-1 (sFlt-1) rise in BPH/5 mice at midgestation. These data show that elevated Cox2 during implantation contributes to placental angiogenic factor imbalances in the BPH/5 mouse model of PE.

Angiogenic factor imbalance precedes complement deposition in placentae of the BPH/5 model of preeclampsia

Preeclampsia (PE), a hypertensive disorder of pregnancy, is a leading cause of maternal and fetal morbidity and mortality. Although the etiology is unknown, PE is thought to be caused by defective implantation and decidualization in pregnancy. Pregnant blood pressure high (BPH)/5 mice spontaneously develop placentopathies and maternal features of human PE. We hypothesized that BPH/5 implantation sites have transcriptomic alterations. Next-generation RNA sequencing of implantation sites at peak decidualization, embryonic day (E)7.5, revealed complement gene up-regulation in BPH/5 vs. controls. In BPH/5, expression of complement factor 3 was increased around the decidual vasculature of E7.5 implantation sites and in the trophoblast giant cell layer of E10.5 placentae. Altered expression of VEGF pathway genes in E5.5 BPH/5 implantation sites preceded complement dysregulation, which correlated with abnormal vasculature and increased placental growth factor mRNA and VEGF₁₆₄ expression at E7.5. By E10.5, proangiogenic genes were down-regulated, whereas antiangiogenic sFlt-1 was up-regulated in BPH/5 placentae. We found that early local misexpression of VEGF genes and abnormal decidual vasculature preceded sFlt-1 overexpression and increased complement deposition in BPH/5 placentae. Our findings suggest that abnormal decidual angiogenesis precedes complement activation, which in turn contributes to the aberrant trophoblast invasion and poor placentation that underlie PE.-Sones, J. L., Merriam, A. A., Seffens, A., Brown-Grant, D.-A., Butler, S. D., Zhao, A. M., Xu, X., Shawber, C. J., Grenier, J. K., Douglas, N. C. Angiogenic factor imbalance precedes complement deposition in placentae of the BPH/5 model of preeclampsia.