Lymphocyte characterization of decidua basalis spiral arteries with acute atherosis in preeclamptic and normotensive pregnancies.

Uteroplacental acute atherosis (AA) is a common spiral arterial lesion in preeclampsia, characterized by intramural foam cells, fibrinoid necrosis, and a perivascular immune cell infiltrate. A clear definition of this infiltrate is lacking. Therefore, our aim was to characterize lymphocytes in pre-defined zones regarding spiral arteries with or without AA, from preeclamptic and normotensive pregnancies. Lymphocytes were characterized in decidua basalis samples (n = 91), previously evaluated for AA, around spiral arteries in three pre-defined zones; 1) intramural, 2) perivascular and 3) interstitial. Adjacent serial sections were immunostained to identify different T-cell populations (CD3+, CD8+, FOXP3+), and NK-cells (CD56+). CD3+CD8- T-cells were also identified. These were presumed to be largely CD4+ T-cells. AA was associated with significantly higher intramural CD3+ cell concentrations in Zone 1, in both normotensives and preeclamptics. In preeclamptics only, this difference extended into Zone 2. Similar results were observed for CD3+CD8- cells. AA was also associated with increased intramural CD8+ concentration; however, the number of cells was low. Regulatory T-cells (FOXP3+) were generally scarce or absent in all pre-defined zones. Although intramural NK-cells (CD56+) were scarce, the intramural concentration was significantly lower in spiral arteries with AA compared to without AA in preeclamptics. Our main finding was that CD3+CD8-FoxP3- T-cells were associated with AA. We therefore suggest that T-cells, of a non-regulatory CD4+ subtype, could be involved in the formation of spiral artery AA in the decidua basalis. Whether AA gives rise to, or is partly mediated by increased T-cell concentration around the lesions, remains to be determined.

Predicting delivery of a small-for-gestational-age infant and adverse perinatal outcome in women with suspected pre-eclampsia.

OBJECTIVE: To evaluate the test performance of 47 biomarkers and ultrasound parameters for the prediction of delivery of a small-for-gestational-age (SGA) infant and adverse perinatal outcome in women presenting with suspected pre-eclampsia. METHODS: This was a prospective, multicenter observational study in which 47 biomarkers and ultrasound parameters were measured in 397 women with a singleton pregnancy presenting with suspected preterm pre-eclampsia between 20 + 0 and 36 + 6 weeks' gestation, with the objective of evaluating them as predictors of subsequent delivery of a SGA infant and adverse perinatal outcome. Women with confirmed pre-eclampsia at enrollment were excluded. Factor analysis and stepwise logistic regression were performed in two prespecified groups stratified according to gestational age at enrollment. The primary outcome was delivery of a SGA infant with a birth weight < 3rd customized centile (SGA-3), and secondary outcomes were a SGA infant with a birth weight < 10th customized centile and adverse perinatal outcome. RESULTS: In 274 women presenting at 20 + 0 to 34 + 6 weeks' gestation, 96 (35%) delivered a SGA-3 infant. For prediction of SGA-3, low maternal placental growth factor (PlGF) concentration had a sensitivity of 93% (95% CI, 84-98%) and negative predictive value (NPV) of 90% (95% CI, 76-97%) compared with a sensitivity of 71% (95% CI, 58-82%) and a NPV of 79% (95% CI, 68-87%) for ultrasound parameters (estimated fetal weight or abdominal circumference < 10th centile). No individual biomarker evaluated had a better performance than did PlGF, and marker combinations made only small improvements to the test performance. Similar results were found in 123 women presenting between 35 + 0 and 36 + 6 weeks' gestation. CONCLUSION: In women presenting with suspected preterm pre-eclampsia, measurement of PlGF offers a useful adjunct for identifying those at high risk of delivering a SGA infant, allowing appropriate surveillance and timely intervention. © 2017 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Diagnostic accuracy of placental growth factor and ultrasound parameters to predict the small-for-gestational-age infant in women presenting with reduced symphysis-fundus height.

OBJECTIVES: To assess the diagnostic accuracy of placental growth factor (PlGF) and ultrasound parameters to predict delivery of a small-for-gestational-age (SGA) infant in women presenting with reduced symphysis-fundus height (SFH). METHODS: This was a multicenter prospective observational study recruiting 601 women with a singleton pregnancy and reduced SFH between 24 and 37 weeks' gestation across 11 sites in the UK and Canada. Plasma PlGF concentration < 5(th) centile, estimated fetal weight (EFW) < 10(th) centile, umbilical artery Doppler pulsatility index > 95(th) centile and oligohydramnios (amniotic fluid index < 5 cm) were compared as predictors for a SGA infant < 3(rd) customized birth-weight centile and adverse perinatal outcome. Test performance statistics were calculated for all parameters in isolation and in combination. RESULTS: Of the 601 women recruited, 592 were analyzed. For predicting delivery of SGA < 3(rd) centile (n = 78), EFW < 10(th) centile had 58% sensitivity (95% CI, 46-69%) and 93% negative predictive value (NPV) (95% CI, 90-95%), PlGF had 37% sensitivity (95% CI, 27-49%) and 90% NPV (95% CI, 87-93%); in combination, PlGF and EFW < 10(th) centile had 69% sensitivity (95% CI, 55-81%) and 93% NPV (95% CI, 89-96%). The equivalent receiver-operating characteristics (ROC) curve areas were 0.79 (95% CI, 0.74-0.84) for EFW < 10(th) centile, 0.70 (95% CI, 0.63-0.77) for low PlGF and 0.82 (95% CI, 0.77-0.86) in combination. CONCLUSIONS: For women presenting with reduced SFH, ultrasound parameters had modest test performance for predicting delivery of SGA < 3(rd) centile. PlGF performed no better than EFW < 10(th) centile in determining delivery of a SGA infant.

Interleukin-1 family cytokines and their regulatory proteins in normal pregnancy and pre-eclampsia.

Maternal systemic inflammation is a feature of pre-eclampsia, a condition in pregnancy characterized by hypertension and proteinuria. Pre-eclampsia is caused by the placenta; many placental factors contribute to the syndrome's progression, and proinflammatory cytokines have been identified previously as one such mediator. The interleukin (IL)-1 family of cytokines are key regulators of the inflammatory network, and two naturally occurring regulatory molecules for IL-1 family cytokines, IL-1RA and sST2, have been found previously to be elevated in maternal blood from women with pre-eclampsia. Here we investigate more recently identified IL-1 family cytokines and regulatory molecules, IL-1RAcP, IL-37, IL-18BP, IL-36α/ß/γ/Ra and IL-38 in pre-eclampsia. Pregnant women have more circulating IL-18BP and IL-36Ra than non-pregnant women, and sIL-1RAcP is elevated from women with pre-eclampsia compared to normal pregnancies. The placenta expresses all the molecules, and IL-37 and IL-18BP are up-regulated significantly in pre-eclampsia placentas compared to those from normal pregnancies. Together, these changes contribute to the required inhibition of maternal systemic cytotoxic immunity in normal pregnancy; however, in pre-eclampsia the same profile is not seen. Interestingly, the increased circulating levels of sIL-1RAcP and increased placental IL-18BP and IL-37, the latter of which we show to be induced by hypoxic damage to the placenta, are all factors which are anti-inflammatory. While the placenta is often held responsible for the damage and clinical symptoms of pre-eclampsia by the research community, here we show that the pre-eclampsia placenta is also trying to prevent inflammatory damage to the mother.

Antenatal cardiotocogram quality and interpretation using computers.

OBJECTIVE: To test the application in practice of computerized fetal heart rate (FHR) analysis in pregnancy. DESIGN: Randomized distribution of subjects with computerized analysis automatically revealed or concealed. SETTING: A district general hospital and a teaching hospital outside London. SUBJECTS: 2869 pregnant women studied within a year. OUTCOME MEASURES: Quality and duration of the cardiotocogram; quantitative measurement of FHR variation; number of stillbirths. RESULTS: With interactive advice to the operator, records were of improved quality (up to 28% without signal loss) with potentially much reduced recording time. The short-term FHR variation measured in the last records before intervention is reported for the first time. CONCLUSION: The benefits of using the computers include improvement in record quality and saving of time. In addition, where interpretation depended on estimation of FHR variation there was prima facie evidence of observer misinterpretation; visual analysis was unreliable. A larger trial is now required with more rigorous constraints on intervention.

Phase-rectified signal averaging for intrapartum electronic fetal heart rate monitoring is related to acidaemia at birth.

OBJECTIVE: Recent studies suggest that phase-rectified signal averaging (PRSA), measured in antepartum fetal heart rate (FHR) traces, may sensitively indicate fetal status; however, its value has not been assessed during labour. We determined whether PRSA relates to acidaemia in labour, and compare its performance to short-term variation (STV), a related computerised FHR feature. DESIGN: Historical cohort. SETTING: Large UK teaching hospital. POPULATION: All 7568 Oxford deliveries that met the study criteria from April 1993 to February 2008. METHODS: We analysed the last 30 minutes of the FHR and associated outcomes of infants. We used computerised analysis to calculate PRSA decelerative capacity (DC(PRSA)), and its ability to predict umbilical arterial blood pH ≤ 7.05 using receiver operator characteristic (ROC) curves and event rate estimates (EveREst). We compared DC(PRSA) with STV calculated on the same traces. MAIN OUTCOME MEASURE: Umbilical arterial blood pH ≤ 7.05. RESULTS: We found that PRSA could be measured in all cases. DC(PRSA) predicted acidaemia significantly better than STV: the area under the ROC curve was 0.665 (95% CI 0.632-0.699) for DC(PRSA), and 0.606 (0.573-0.639) for STV (P = 0.007). EveREst plots showed that in the worst fifth centile of cases, the incidence of low pH was 17.75% for DC(PRSA) but 11.00% for STV (P < 0.001). DC(PRSA) was not highly correlated with STV. CONCLUSIONS: DC(PRSA) of the FHR can be measured in labour, and appears to predict acidaemia more accurately than STV. Further prospective evaluation is warranted to assess whether this could be clinically useful. The weak correlation between DC(PRSA) and STV suggests that they could be combined in multivariate FHR analyses.

The effect of augmentation of labour with syntocinon on the fetal CTG using objective computerised analysis: a nested case-control study.

OBJECTIVE: To investigate the effect of syntocinon augmentation on the fetal cardiotocogram (CTG) using computerised analysis. We hypothesised that syntocinon will have no direct effects on the fetal heart rate if used correctly. STUDY DESIGN: A retrospective, nested case-control study. SETTING: Intrapartum CTG records from the digital archive at the John Radcliffe Hospital, Oxford, UK. SUBJECTS: 110 women with singleton pregnancies of >36 weeks gestation, no known congenital abnormality, spontaneous onset of labour and syntocinon augmentation for failure to progress, with start time of syntocinon recorded, from between August 1998 and December 1999, extensively matched to 110 controls who had normally progressing labours. METHODS: Eight different CTG features were measured during four time points with OxSys, a computerised numerical analysis system. STATISTICAL ANALYSIS: Differences in the CTG features over time in cases and controls using ANOVA and Friedman's ANOVA and at each time point between case-control pairs using Student's t-test and the Wilcoxon signed rank test. RESULTS: After administration, syntocinon increased the frequency, decreased the duration and decreased the resting time between contractions (p<0.001), resulting in no significant difference between normally progressing labours and those requiring augmentation. The case group had a significantly higher signal stability index (SSI) and fewer decelerations compared to the control group - differences which disappeared after augmentation was commenced (p=0.025 and 0.033 respectively). Syntocinon did not affect the baseline heart rate, short term variability (STV) or phase rectified signal averaging (PRSA) (p=0.518, 0.215 and 0.138) in comparison with controls. There was a significant increase in the PRSA in babies born with acidaemia (arterial pH≤7.05) 60-120min after syntocinon was commenced that was not seen with in babies with a normal pH (p=0.002). CONCLUSION: Syntocinon "normalises" ineffective uterine activity without any direct effect on the fetal heart rate. Therefore its administration does not confound objective computerised analysis. There may be a specific response in PRSA shortly after commencing syntocinon augmentation in the fetus which is subsequently born acidaemic which requires further investigation.

IFPA Award in Placentology Lecture: preeclampsia, the decidual battleground and future maternal cardiovascular disease.

The decidua basalis is one of the frontiers between placenta and mother. Its spiral arteries ensure that the placenta and fetus have adequate access to the maternal circulation, without compromising maternal health. Normally this requires a tightly regulated collaboration between tissues of genetically different individuals. But like all frontiers it can become a battlefield. The decidua is difficult to sample systematically. Some of the problems have been resolved by our vacuum suction method. We review the technique and how it has contributed to what we know of decidual tissue, especially when it becomes a battlefield in preeclampsia, with its increased oxidative stress and inflammation. Acute atherosis is a poorly studied decidual lesion of late pregnancy, which mainly affects the decidual tips of spiral arteries in preeclampsia. It is characterized by lipid-filled foam cells and resembles early atherosclerosis. Poorly remodelled spiral arteries seem to be especially susceptible. The underlying mechanisms are largely unknown, but are likely to be similar to those of atherosclerosis and primarily the consequence of vascular inflammation. Acute atherosis also occurs in other pregnancy complications, even in normal pregnancies. It appears not to be confined to maladapted spiral arteries nor be caused by hypertension. It is important that foam cells result from inflammatory stimulation of macrophages. Hence, we propose that decidual inflammation of multiple causes underlies acute atherosis, with or without preeclampsia. Women suffering from preeclampsia have an augmented risk of cardiovascular disease later in life and of premature death. Acute atherosis may more specifically identify those women at augmented risk for such later cardiovascular disorders, whether or not it is associated with preeclampsia.

Review: Preeclampsia, acute atherosis of the spiral arteries and future cardiovascular disease: two new hypotheses.

Preeclampsia is a serious complication of pregnancy, potentially lethal for women and offspring. Affected women have an augmented risk of later cardiovascular disease and premature death and may have risk factors in common with older persons developing cardiovascular disease. In some cases of preeclampsia, lipid-filled foam cells accumulate in the walls of the spiral arteries of the uteroplacental circulation (acute atherosis). These lesions resemble the early stages of atherosclerosis and are thought to regress after delivery. The mechanisms that contribute to acute atherosis are largely unknown, but are related to defective vascular remodeling of the spiral arteries in the first half of pregnancy. Spiral artery lipid deposition may also occur in normal pregnancies, which suggests that it may not be confined exclusively to maladapted spiral arteries or caused by hypertension. Our first hypothesis is that there are several pathways to the development of acute atherosis, which converge at the point of excessive decidual inflammation in the final common pathway. Our second hypothesis is that acute atherosis, evolving during the short time of pregnancy, identifies a subset of women at augmented risk for atherosclerosis and later chronic arterial disease better than the diagnosis of preeclampsia itself. If confirmed, this may enable better preventive management for the affected women.

Stress responses and pre-eclampsia.

Biological stress may affect individual cells, tissues or whole organisms, arising from disturbed homoeostasis of any cause. Stress is rarely localised. Because biological systems are closely integrated, it spreads to involve other systems. Stress responses are highly integrated and work to restore homoeostasis. Different response pathways overlap and interlink. If the responses fail or decompensate, distress ensues, of which the end-stage is death. Pre-eclampsia results from a series of biological stresses, possibly from conception, which become established by abnormal placentation and affect the mother, her foetus and her placenta. The stresses involve dialogue between mother and placenta. Even a normal placenta imposes substantial stress on maternal systems. When placental growth and perfusion is abnormal (poor placentation) then the placenta, particularly its outer trophoblast layer, becomes stressed - loosely denoted hypoxic damage or oxidative stress. Signals from the placenta spread the stress to the mother, who develops signs of pre-eclampsia. Cellular stress sensors initiate stress responses. Different stresses may trigger similar responses in specific cell types. The first cell response is reduced protein synthesis. However some synthetic pathways are spared or activated to produce stress signals. In relation to pre-eclampsia and the placenta, an excessive release of sFlt-1 a soluble decoy receptor for vascular endothelial growth factor (VEGF) is a trophoblast related stress signal. SFlt1 perturbs the angiogenic balance in the maternal circulation and is considered to cause many of the specific features of the maternal syndrome in pre-eclampsia. Three key points will be emphasised. First, multiple stressors, not simply hypoxia, stimulate the release of sFlt-1 from trophoblast. Second, sFlt-1 is only one of the group of stress signals delivered by trophoblast to the mother. Third, sFlt-1 is not the only trophoblast derived factor to perturb the maternal circulation in pre-eclampsia.

Relation of fetal heart rate signals with unassignable baseline to poor neonatal state at birth.

Electronic fetal heart rates (FHR) are used to monitor fetal health during labour. The paper records are visually assessed by clinicians, but automated alternatives are being developed. Interpretation, visual or computerised, depends on assigning a baseline to identify key features such as accelerations and decelerations. However, when the FHR is unstable the baseline may be unassignable, making conventional analysis unreliable. Such instability may reflect on fetal health. If true, these segments should not be discarded but quantified, for which we have developed a numerical method. In 7,568 labours, the association between unassignable baseline and umbilical arterial blood pH ≤ 7.05 at birth (evidence of poor health) was studied retrospectively. We found a consistent increase of the risk for acidaemia with longer intervals of unassignable baseline. This is detectable at the end of the first stage of labour, but stronger at the end of the second stage: in the last 30 min of labour, the odds ratios (with respect to baseline assignable throughout this period) increased from 1.99 (15 min unassignable) to 4.9 (30 min unassignable). Computerised analysis of the FHR becomes unreliable when the baseline cannot be assigned; however, this pattern is itself a pathological feature associated with acidaemia at birth.

Review: Does size matter? Placental debris and the pathophysiology of pre-eclampsia.

A variety of 'debris' is shed from the syncytial surface of the human placenta ranging from large deported multinuclear fragments to sub-cellular components. It is increasingly clear that at least some of this material has signalling functions. Many categories of circulating debris are increased in pre-eclampsia, and exhibit proteins that are pro-inflammatory and could contribute to the systemic inflammatory response in normal pregnancy, which is exaggerated in pre-eclampsia. It is now evident that there is a large 'hidden' population of microvesicles and nanovesicles (including exosomes) which are hard to investigate because of their size. We have used a new technology, nanoparticle tracking analysis, to measure the size and concentration of syncytiotrophoblast vesicles prepared by placental perfusion. The vesicles range in size from 50 nm to 1 µm with the majority being <500 nm (which includes both exosomes and microvesicles). We speculate whether changes not only in the numbers, but also in the size (beneficial syncytiotrophoblast exosomes and harmful microvesicles) might be important in the maternal syndrome of pre-eclampsia.

Highly comparative fetal heart rate analysis.

A database of fetal heart rate (FHR) time series measured from 7 221 patients during labor is analyzed with the aim of learning the types of features of these recordings that are informative of low cord pH. Our 'highly comparative' analysis involves extracting over 9 000 time-series analysis features from each FHR time series, including measures of autocorrelation, entropy, distribution, and various model fits. This diverse collection of features was developed in previous work [1]. We describe five features that most accurately classify a balanced training set of 59 'low pH' and 59 'normal pH' FHR recordings. We then describe five of the features with the strongest linear correlation to cord pH across the full dataset of FHR time series. The features identified in this work may be used as part of a system for guiding intervention during labor in future. This work successfully demonstrates the utility of comparing across a large, interdisciplinary literature on time-series analysis to automatically contribute new scientific results for specific biomedical signal processing challenges.

IFPA Meeting 2010 Workshop Report I: Immunology; ion transport; epigenetics; vascular reactivity; epitheliochorial placentation; proteomics.

Workshops are an important part of the IFPA annual meeting. At IFPA Meeting 2010 there were twelve themed workshops, six of which are summarized in this report. 1. The immunology workshop focused on normal and pathological functions of the maternal immune system in pregnancy. 2. The transport workshop dealt with regulation of ion and water transport across the syncytiotrophoblast of human placenta. 3. The epigenetics workshop covered DNA methylation and its potential role in regulating gene expression in placental development and disease. 4. The vascular reactivity workshop concentrated on methodological approaches used to study placental vascular function. 5. The workshop on epitheliochorial placentation covered current advances from in vivo and in vitro studies of different domestic species. 6. The proteomics workshop focused on a variety of techniques and procedures necessary for proteomic analysis and how they may be implemented for placental research.

Computerised electronic foetal heart rate monitoring in labour: automated contraction identification.

The foetal heart rate (FHR) response to uterine contractions is crucial to detect foetal distress by electronic FHR monitoring during labour. We are developing a new automated system (OxSys) for decision support in labour, using the Oxford database of intrapartum FHR records. We describe here a novel technique for automated detection of uterus contractions. In addition, we present a comparison of the new method with four other computerised approaches. During training, OxSys achieved sensitivity above 95% and positive predictive value (PPV) of up to 90% for traces of good quality. During testing, OxSys achieved sensitivity = 87% and PPV = 75%. For comparison, a second clinical expert obtained sensitivity = 93% and PPV = 80%, and all other computerised approaches achieved lower values. It was concluded that the proposed method can be employed with confidence in our study on foetal health assessment in labour and future OxSys development.

Computerized analysis of normal fetal heart rate pattern throughout gestation.

OBJECTIVE: To analyze the evolution of computerized cardiotocography (cCTG) parameters throughout gestation in a large archive of traces from healthy fetuses. METHODS: This was a cross-sectional study of the first cCTG record from 4412 singleton fetuses with good pregnancy outcome. Normal ranges of cCTG parameters for 25 to 42 weeks were derived from analysis of only one cCTG record per fetus, and the relationship between the parameters and gestational age was investigated. RESULTS: Fetal heart rate (FHR) accelerations, short- and long-term variation overall, duration of episodes of high and low variation and variation in high episodes increased with advancing gestation. In contrast, maternal perception of fetal movements, basal FHR, variation in low episodes and the time until criteria for normality were met decreased with advancing gestation. Gestational age-related changes in FHR variation were less evident at the lowest percentiles. Episodes of high FHR variation were detected in most fetuses, even at 25 weeks. Opposite trends of basal FHR and variation were observed at 42 weeks. Large decelerations and the frequency and duration of low episodes were also higher at 42 weeks. CONCLUSIONS: The characteristics of the normal FHR pattern are quite defined from early on in gestation, follow a continuous trend with advancing gestation and change abruptly at 42 weeks. Gestational age-related changes are less obvious at the lowest percentiles.

Placental stress and pre-eclampsia: a revised view.

In pre-eclampsia, poor placentation causes both oxidative and endoplasmic reticulum stress of the placenta. It is believed placental hypoxia stimulates excessive production of soluble fms-like tyrosine kinase 1 (sFlt-1), which binds and deactivates circulating vascular endothelial growth factor (VEGF). When maternal endothelium is deprived of VEGF it becomes dysfunctional hence leading to the clinical syndrome of the mother. In this paper the previous claim that poor placentation may predispose more to placental oxidative stress than hypoxia is reiterated. We show why pre-eclampsia is not only an endothelial disease, but also a disorder of systemic inflammation. We question that hypoxia is the only or indeed the main stimulus to release of sFlt-1; and emphasise the role of inflammatory mechanisms. Hypoxia cannot be assumed simply because hypoxia-inducible transcription factors (HIF) are upregulated. Concurrent assessments of nuclear factor-kappaB (NF-kappaB), a transcription factor for inflammatory responses are desirable to obtain a more complete picture. We point out that the pre-eclampsia placenta is the source of bioactive circulating factors other than sFlt-1 in concentrations that are much higher than in normal pregnancy. These may also contribute to the final inflammatory syndrome. We propose a modified version of the two-stage model for pre-eclampsia.