An ultrastructural study of utero-placental spiral arteries in hypertensive and normotensive pregnancy and fetal growth retardation

Homeobox genes in the human placenta: Twists and turns on the path to find novel targets

Fetal growth restriction (FGR) is a clinically important human pregnancy disorder that is thought to originate early in pregnancy and while its aetiology is not well understood, the disorder is associated with placental insufficiency. Currently treatment for FGR is limited by increased surveillance using ultrasound monitoring and premature delivery, or corticosteroid medication in the third trimester to prolong pregnancy. There is a pressing need for novel strategies to detect and treat FGR at its early stage. Homeobox genes are well established as master regulators of early embryonic development and increasing evidence suggests they are also important in regulating early placental development. Most important is that specific homeobox genes are abnormally expressed in human FGR. This review focusses on identifying the molecular pathways controlled by homeobox genes in the normal and FGR-affected placenta. This information will begin to address the knowledge gap in the molecular aetiology of FGR and lay the foundation for identifying potential diagnostic and therapeutic targets.

B-flow/spatiotemporal image correlation M-mode ultrasound provides novel method to quantify spiral artery remodeling during normal human pregnancy

OBJECTIVES

During human pregnancy, placental extravillous trophoblasts replace vascular smooth muscle and elastic tissue within the walls of the uterine spiral arteries, thereby remodeling them into distensible low-resistance vessels to promote placental perfusion. The present study determined whether B-flow/spatiotemporal image correlation (STIC) M-mode ultrasonography provides an in-vivo imaging method able to digitally quantify spiral artery luminal distensibility as a physiological index of spiral artery remodeling during the advancing stages of normal human pregnancy.

METHODS

A prospective, longitudinal, observational study was conducted to quantify spiral artery distensibility (i.e. vessel luminal diameter at systole minus diameter at diastole) by B-flow/STIC M-mode ultrasonography during the first, second and third trimesters in 290 women exhibiting a normal pregnancy. Maternal serum levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1), growth factors that modulate important events in spiral artery remodeling, were quantified in a subset of the women in the first, second and third trimesters of pregnancy.

RESULTS

Median (interquartile range (IQR)) spiral artery distensibility increased progressively between the first (0.17 (0.14-0.21) cm), second (0.23 (0.18-0.28) cm) and third (0.26 (0.21-0.35) cm) trimesters of pregnancy (P < 0.0001 for all). Median (IQR) spiral artery volume flow increased progressively between the first (2.49 (1.38-4.99) mL/cardiac cycle), second (3.86 (2.06-6.91) mL/cardiac cycle) and third (7.79 (3.83-14.98) mL/cardiac cycle) trimesters (P < 0.001 for all). In accordance with the elevation in spiral artery distensibility, the median (IQR) ratio of serum PlGF/sFlt-1 × 103 levels increased between the first (7.2 (4.5-10.0)), second (22.7 (18.6-42.2)) and third (56.2 (41.9-92.5)) trimesters (P < 0.001 for all).

CONCLUSIONS

The present study shows that B-flow/STIC M-mode ultrasonography provides an in-vivo imaging technology to quantify digitally the structural and physiological expansion of the walls of the spiral arteries during the cardiac cycle as a consequence of their transformation into compliant vessels during advancing stages of normal human pregnancy. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Ophthalmic artery Doppler and biomarkers of impaired placentation at 36 weeks' gestation in pregnancies with small fetuses

OBJECTIVES

First, to compare ophthalmic artery peak systolic velocity (PSV) ratio and biomarkers of impaired placentation at 36 weeks' gestation in women who delivered a small-for-gestational-age (SGA) or growth-restricted (FGR) neonate, in the absence of hypertensive disorder, with those of women who developed pre-eclampsia (PE) or gestational hypertension (GH) and of women unaffected by SGA, FGR, PE or GH. Second, to examine the associations of PSV ratio, uterine artery pulsatility index (UtA-PI), placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) with birth-weight Z-score or percentile.

METHODS

This was a prospective observational study of women with a singleton pregnancy attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination of fetal anatomy and growth, and measurement of maternal ophthalmic artery PSV ratio, UtA-PI, PlGF and sFlt-1. Values of PSV ratio, UtA-PI, PlGF and sFlt-1 were converted to multiples of the median (MoM) or delta values. Median MoM or deltas of these biomarkers in the SGA, FGR, PE and GH groups were compared with those in the unaffected group. Regression analysis was used to examine the relationship of PSV ratio delta, UtA-PI MoM, PlGF MoM and sFlt-1 MoM with birth-weight Z-score, after exclusion of PE and GH cases.

RESULTS

The study population of 9033 pregnancies included 7696 (85.2%) that were not affected by FGR, SGA, PE or GH, 182 (2.0%) complicated by FGR in the absence of PE or GH, 698 (7.7%) with SGA in the absence of FGR, PE or GH, 236 (2.6%) with PE and 221 (2.4%) with GH. Compared with unaffected pregnancies, in the FGR and SGA groups, the PSV ratio delta and sFlt-1 MoM were increased and PlGF MoM was decreased; UtA-PI MoM was increased in the FGR group but not the SGA group. The magnitude of the changes in biomarker values relative to the unaffected group was smaller in the FGR and SGA groups than that in the PE and GH groups. In non-hypertensive pregnancies, there were significant inverse associations of PSV ratio delta and UtA-PI MoM with birth-weight Z-score, such that the values were increased in small babies and decreased in large babies. There was a quadratic relationship between PlGF MoM and birth-weight Z-score, with low PlGF levels in small babies and high PlGF levels in large babies. There was no significant association between sFlt-1 MoM and birth-weight Z-score.

CONCLUSIONS

Ophthalmic artery PSV ratio, reflective of peripheral vascular resistance, and UtA-PI, PlGF and sFlt-1, biomarkers of impaired placentation, are altered in pregnancies complicated by hypertensive disorder and, to a lesser extent, in non-hypertensive pregnancies delivering a SGA or FGR neonate. The associations between the biomarkers and birth-weight Z-score suggest the presence of a continuous physiological relationship between fetal size and peripheral vascular resistance and placentation, rather than a dichotomous relationship of high peripheral resistance and impaired placentation in small compared to non-small fetuses. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Predictive role of Doppler indices of cerebral-placental-uterine ratio and umbilico-cerebral ratio for late-onset fetal growth restriction: a prospective cohort study

Predicting late-onset foetal growth restriction (FGR) has proven to be rather challenging. In this study, we propose a new parameter, cerebral-placental-uterine (CPU) ratio and umbilico-cerebral (UC) ratio for this matter. Results of this study which included a total of 227 nulliparous women showed that an increase in CPU ratio (OR = 0.45; 95% CI: 0.23-0.88; p=.020) was associated with lower odds of foetal weight above the 10th percentile at birth. CPU ratio measured at 35-37 weeks of gestation had an AUC of 0.78 (95% CI: 0.58, 0.98), sensitivity of 0.62 (95% CI: 0.24, 0.91) and specificity of 0.90 (95% CI: 0.79, 0.96) for prediction of late-onset FGR, which showed higher accuracy than UC ratio. As some cases of the late-onset FGR are not diagnosed by foetal biometry, it is important to find Doppler parameters that can help us predict these cases and CPU ratio may help physicians in detection of high-risk foetuses that will benefit from earlier intervention. Impact StatementWhat is already known on this subject? Late-onset foetal growth restriction (FGR) defined by an FGR diagnosis after 32 weeks of gestational age, can lead to short- and long-term morbidities and early diagnosis is the key to prevent these complications.What do the results of this study add? Results showed that each unit increase in numeric variables including CP ratio (OR = 0.29, p=.006), and CPU ratio (OR = 0.40, p=.006) was associated with lower odds of the foetal weight above the 10th percentile in the second ultrasound at 35-37 weeks. In other words, CPU ratio can prove to be useful marker in prediction of late-onset FGR.What are the implications of these findings for clinical practice and/or further research? Our prospective cohort study confirms the added value of low CPU ratio, with higher predictive accuracy than UC ratio, in predicting late-onset FGR. Detection of late FGR remains poor, but it is important to prevent stillbirth so further studies on the role of CPU ratio in predicting FGR and perinatal outcomes are needed.

Ophthalmic artery Doppler at 35-37 weeks' gestation in pregnancies with small or growth-restricted fetuses

OBJECTIVES

First, to compare the ophthalmic artery peak systolic velocity (PSV) ratio at 35-37 weeks' gestation among women who delivered small-for-gestational-age (SGA) or growth-restricted (FGR) neonates in the absence of hypertensive disorders, women who developed pre-eclampsia (PE) or gestational hypertension (GH) and those without SGA, FGR, PE or GH. Second, to examine the association of PSV ratio with placental growth factor (PlGF) and mean arterial pressure (MAP). Third, to assess the associations of PSV ratio, PlGF and MAP with birth-weight Z-score and percentile.

METHODS

This was a prospective observational study in women attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination of fetal anatomy and growth, and measurement of maternal ophthalmic artery PSV ratio, first (PSV1) and second (PSV2) peaks of systolic velocity, MAP and serum PlGF. The values of PSV ratio, MAP and PlGF were converted to multiples of the median (MoM) or delta values, and the median MoM or delta of these variables in the SGA, FGR, PE and GH groups were compared with those in the unaffected group. Regression analysis was used to examine the relationship of PSV ratio delta, PlGF MoM and MAP MoM with birth-weight Z-score after exclusion of PE and GH cases. Regression analysis was also used to examine the association of PSV ratio delta with log₁₀ PlGF MoM and log₁₀ MAP MoM.

RESULTS

The study population included 2287 pregnancies, of which 1954 (85.4%) were not affected by FGR, SGA, PE or GH, 49 (2.1%) were complicated by FGR in the absence of PE or GH, 160 (7.0%) had SGA in the absence of FGR, PE or GH, 60 (2.6%) had PE and 64 (2.8%) had GH. Compared with unaffected pregnancies, in both the FGR and SGA groups, the means of PSV ratio delta (0.042 (95% CI, 0.007-0.076) and 0.032 (95% CI, 0.016-0.049), respectively) and MAP MoM (1.028 (95% CI, 1.006-1.050) and 1.048 (95% CI, 1.035-1.060), respectively) were increased, while the mean of PlGF MoM was decreased (0.495 (95% CI, 0.393-0.622) and 0.648 (95% CI, 0.562-0.747), respectively). However, the magnitude of these changes was smaller than in the PE and GH groups. Ophthalmic artery waveform analysis revealed that the predominant feature of pregnancies complicated by SGA in the absence of hypertensive disorders was a reduction in PSV1, whereas, in those with hypertensive disorders, there was an increase in PSV2. In non-hypertensive pregnancies, there were linear inverse associations of PSV ratio delta and MAP MoM with birth-weight Z-score, with increased values in small neonates and decreased values in large neonates. There was a quadratic relationship between PlGF MoM and birth-weight Z-score, with low PlGF levels in small neonates and high PlGF levels in large neonates. There was a significant correlation of ophthalmic artery PSV ratio delta with both log₁₀ MAP MoM (0.124 (95% CI, 0.069-0.178)) and log₁₀ PlGF MoM (-0.238 (95% CI, -0.289 to -0.185)).

CONCLUSION

Assuming that the ophthalmic artery PSV ratio is a reflection of the interplay between cardiac output and peripheral vascular resistance, the linear association between PSV ratio and birth-weight Z-score in non-hypertensive pregnancies suggests the presence of a continuous physiological relationship between fetal size and cardiovascular response rather than a dichotomous relationship between high peripheral resistance and low cardiac output in small compared with non-small fetuses. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Platelets in Fetal Growth Restriction: Role of Reactive Oxygen Species, Oxygen Metabolism, and Aggregation

Fetal growth restriction (FGR) is mainly caused by failure of the uteroplacental unit. The exact pathogenesis remains unclear. The cause is thought to be related to abnormal platelet activation, which may result in microthrombus formation in the small vessels of the placenta. Reactive oxygen species (ROS) may initiate the pathological process of platelet activation. This study aimed to evaluate selected platelet parameters in pregnancy complicated by FGR and relate them to the severity of hemodynamic abnormalities. A total of 135 women (pregnant with FGR, with an uncomplicated pregnancy, and non-pregnant) were enrolled to study different platelet parameters: count (PLT), mean volume (MPV), ROS levels, intracellular oxygen level, oxygen consumption, and aggregation indices. No abnormalities in PLT and MPV were found in the FGR group, although it revealed increased ROS levels in platelets, lower platelet oxygen consumption, and intraplatelet deprivation. Aggregation parameters were similar as in uncomplicated pregnancy. No significant relationships were observed between hemodynamic abnormalities and the studied parameters. Platelets in pregnancies complicated by FGR may reveal an impaired oxidative metabolism, which may, in turn, lead to oxidative stress and, consequently, to an impaired platelet function. This study adds to the understanding of the role of platelets in the etiology of FGR.

NF-κB regulation in maternal immunity during normal and IUGR pregnancies

Intrauterine Growth Restriction (IUGR) is a leading cause of perinatal death with no effective cure, affecting 5-10% pregnancies globally. Suppressed pro-inflammatory Th1/Th17 immunity is necessary for pregnancy success. However, in IUGR, the inflammatory response is enhanced and there is a limited understanding of the mechanisms that lead to this abnormality. Regulation of maternal T-cells during pregnancy is driven by Nuclear Factor Kappa B p65 (NF-κB p65), and we have previously shown that p65 degradation in maternal T-cells is induced by Fas activation. Placental exosomes expressing Fas ligand (FasL) have an immunomodulatory function during pregnancy. The aim of this study is to investigate the mechanism and source of NF-κB regulation required for successful pregnancy, and whether this is abrogated in IUGR. Using flow cytometry, we demonstrate that p65⁺ Th1/Th17 cells are reduced during normal pregnancy, but not during IUGR, and this phenotype is enforced when non-pregnant T-cells are cultured with normal maternal plasma. We also show that isolated exosomes from IUGR plasma have decreased FasL expression and are reduced in number compared to exosomes from normal pregnancies. In this study, we highlight a potential role for FasL⁺ exosomes to regulate NF-κB p65 in T-cells during pregnancy, and provide the first evidence that decreased exosome production may contribute to the dysregulation of p65 and inflammation underlying IUGR pathogenesis.

Defective Uteroplacental Vascular Remodeling in Preeclampsia: Key Molecular Factors Leading to Long Term Cardiovascular Disease

Preeclampsia is a complex hypertensive disorder in pregnancy which can be lethal and is responsible for more than 70,000 maternal deaths worldwide every year. Besides the higher risk of unfavorable obstetric outcomes in women with preeclampsia, another crucial aspect that needs to be considered is the association between preeclampsia and the postpartum cardiovascular health of the mother. Currently, preeclampsia is classified as one of the major risk factors of cardiovascular disease (CVD) in women, which doubles the risk of venous thromboembolic events, stroke, and ischemic heart disease. In order to comprehend the pathophysiology behind the linkage between preeclampsia and the development of postpartum CVD, a thorough understanding of the abnormal uteroplacental vascular remodeling in preeclampsia is essential. Therefore, this review aims to summarize the current knowledge of the defective process of spiral artery remodeling in preeclampsia and how the resulting placental damage leads to excessive angiogenic imbalance and systemic inflammation in long term CVD. Key molecular factors in the pathway-including novel findings of microRNAs-will be discussed with suggestions of future management strategies of preventing CVD in women with a history of preeclampsia.

Pathogenesis of uteroplacental acute atherosis: An update on current research

Uteroplacental acute atherosis is a type of arterial vascular disease that affects the placenta during pregnancy and predominates in the maternal spiral arteries in the decidua basalis layer of the pregnant uterus. This condition is characterized by fibrin-like necrosis of the blood vessel walls, the accumulation of macrophages containing fat (foam cells), and the infiltration of macrophages around blood vessels. Uteroplacental acute atherosis is rare in normal pregnancy but occurs more frequently in patients with pregnancy complications, including preeclampsia, spontaneous preterm labor, preterm prelabor rupture of membranes, mid-trimester spontaneous abortion, fetal death, and small-for-gestational age. It is believed that the mechanisms underlying the development of uteroplacental acute atherosis are related to the incomplete physiological transformation of spiral arteries, placental inflammation, abnormal lipid metabolism, and oxidative stress. In this review, we describe the pathogenesis of uteroplacental acute atherosis to provide reference guidelines for the future prevention and treatment of uteroplacental acute atherosclerotic disease.

Immunologic causes and thrombophilia in recurrent pregnancy loss

Certain miscarriages result from immunologic factors, but there is no clear identification of the precise causes of recurrent pregnancy loss (RPL). Miscarriages and RPL can arise from a disruption of maternal-fetal immune homeostasis. Remodeling of the maternal uterine spiral arteries is one of the key steps for normal growth and development of the fetus. An adequate oxygen supply is necessary for correct placentation, and it is accomplished by proper vascular changes. The development of fetal tissues creates a potential immunologic problem since the fetus can express paternal antigens and, in some cases, antigens of a gamete donor. The maternal immune system actively responds to fetal antigens, and dysregulation of this crosstalk could partly explain pregnancy complications such as miscarriages and RPL. RPL resulting from thrombophilia is primarily due to acquired thrombophilia, and therefore screening and treatment should be focused on antiphospholipid antibody syndrome.

Brominated diphenyl ether-47 differentially regulates cellular migration and invasion in a human first trimester trophoblast cell line

Polybrominated diphenyl ethers (PBDEs) are flame retardant compounds detected in human placenta and linked to adverse pregnancy outcomes. Impaired trophoblast migration and invasion during early pregnancy have been implicated as potential mechanisms of pregnancy disorders. The present study investigated the effect of BDE-47, a prevalent PBDE congener, on cell migration, invasion, and matrix metalloproteinase (MMP) expression in a human first trimester extravillous trophoblast cell line, HTR-8/SVneo. BDE-47 stimulated cell migration in HTR-SV/neo cells while decreasing invasion of cells into Matrigel. In addition, BDE-47 led to differential expression of MMP-1, -2, -3, and -9 at protein and mRNA levels. In summary, BDE-47 differentially regulated cellular migration and invasion with divergent changes in MMP expression in trophoblasts. Because proper regulation of trophoblast migration and invasion is critical for placental development and function, further research is warranted to determine if exposure to PBDEs disrupts trophoblast functions with increased risk for adverse pregnancy outcomes.

The role of the renin-angiotensin system in regulating endometrial neovascularization during the peri-implantation period: literature review and preliminary data

BACKGROUND

Implantation is initiated when the blastocyst attaches to the endometrium during the peri-implantation period, and appropriate neovascularization is a prerequisite for the success of the subsequent process. The role of the renin-angiotensin system (RAS) in regulation of blood pressure and hydro-electrolyte balance has long been recognized, while its role in the peri-implantation endometrium remains unclear. This manuscript discusses endometrial RAS and its possible pathways in regulating endometrial angiogenesis and its influence on subsequent pregnancy outcomes.

METHODS

A comprehensive search of electronic databases was carried out to identify relevant published articles, and a literature review was then performed. Using immunohistochemistry, we also performed a pilot study to examine expression of angiotensin II receptors, including angiotensin II type 1 (AT1) receptor (AT1-R) and angiotensin II type 2 (AT2) receptor (AT2-R) in the human endometrium around the time of implantation.

RESULTS

The results of the pilot study showed expression of AT1-R and AT2-R in all endometrial compartments (luminal epithelium, glandular epithelium, stroma cells, and blood vessels), and altered expression was witnessed in women with recurrent miscarriage when compared with fertile control women from our preliminary result.

CONCLUSION

Altered vasculature of the endometrium in the peri-implantation period is detrimental to implantation and may lead to recurrent miscarriage. Being an angiogenic mediators, endometrial RAS may play a role around the time of embryo implantation, affecting subsequent pregnancy outcomes.

Placental bed research: I. The placental bed: from spiral arteries remodeling to the great obstetrical syndromes

The term placental bed was coined to describe the maternal-fetal interface (ie, the area in which the placenta attaches itself to the uterus). Appropriate vascularization of this area is of vital importance for the development of the fetus; this is why systematic investigations of this area have now been carried out. Initially, the challenge was the identification and classification of the various successive branching of uterine arteries in this area. These vessels have a unique importance because failure of their physiological transformation is considered to be the anatomical basis for reduced perfusion to the intervillous space in women with preeclampsia, fetal growth restriction, preterm labor, preterm premature rupture of membranes, abruptio placentae, and fetal death. To investigate in depth the pathophysiology of the placental bed, some 60 years ago, a large number of placental bed biopsies, as well as of cesarean hysterectomy specimens with placenta in situ, from both early and late normotensive and hypertensive pregnancies, were carefully dissected and analyzed. Thanks to the presence of a series of specific physiological changes, characterized by the invasion and substitution of the arterial intima by trophoblast, this material allowed the identification in the placental bed of normal pregnancies of the main vessels, the uteroplacental arteries. It was then discovered that preeclampsia is associated with defective or absent transformation of the myometrial segment of the uteroplacental arteries. In addition, in severe hypertensive disease, atherosclerotic lesions were also found in the defective myometrial segment. Finally, in the basal decidua, a unique vascular lesion, coined acute atherosis, was also identified This disorder of deep placentation, coined defective deep placentation, has been associated with the great obstetrical syndromes, grouping together preeclampsia, intrauterine growth restriction, preterm labor, preterm premature rupture of membranes, late spontaneous abortion, and abruptio placentae. More recently, simplified techniques of tissue sampling have been also introduced: decidual suction allows to obtain a large number of decidual arteries, although their origin in the placental bed cannot be determined. Biopsies parallel to the surface of the basal plate have been more interesting, making possible to identify the vessels' region (central, paracentral, or peripheral) of origin in the placental bed and providing decidual material for immunohistochemical studies. Finally, histochemical and electron microscopy investigations have now clarified the pathology and pathogenetic mechanisms underlying the impairment of the physiological vascular changes.

Preeclampsia: the role of persistent endothelial cells in uteroplacental arteries

We explore the potential role of the endothelial lining of uteroplacental arteries in the pathogenesis of preeclampsia, a severe pregnancy disorder characterized by incomplete invasion of the uterine vasculature by extravillous trophoblast and angiogenic imbalance. In normal pregnancy, the endothelium disappears progressively from the uteroplacental arteries and is replaced by trophoblast and deposition of fibrofibrinoid structure, underpinning the so-called physiological transformation of uterine spiral arteries. We hypothesize that partial persistence of the endothelium, albeit injured, initiates a chain of events leading to the emergence of preeclampsia in 3 sequential stages. The first stage results in retention of the endothelium in uteroplacental arteries secondary to incomplete physiological transformation of the vessels. Consequently, the uteroplacental vessels are reactive to pathological cues, which drives local arteriopathy. The second stage starts with progressive reduction in uteroplacental blood flow, generating oxidative stress in the whole placenta, and heightened maternal inflammation in response to circulating trophoblastic debris. In the third stage, generalized endotheliosis causes systemic angiogenic imbalance, hypertension, and other clinical manifestation of preeclampsia.

Evaluation of fetal medicine foundation algorithm in predicting small-for-gestational-age neonates

OBJECTIVES

To examine the performance of the Fetal Medicine Foundation (FMF) 2012 predictive model and of isolated biophysical markers (uterine artery pulsatility index and mean arterial pressure) for small-for-gestational-age (SGA), in patients from Rio de Janeiro, Brazil.

METHODS

For this cross-sectional study, SGA was diagnosed when a newborn presented birth weight below the fifth percentile for gestational age. FMF2012 algorithm sensitivity and specificity, positive (PPV) and negative (NPV) predictive value, positive likelihood ratio (LR +) and area under the ROC curve (AUC) were calculated to predict total and preterm SGA (SGA < 37). The performance of isolated biophysical markers - mean arterial pressure (MAP) and mean uterine artery pulsatility index (UtAPI) were studied.

RESULTS

The final sample consisted of 1480 cases: 69 (4.6%) developed SGA, including 12 patients (0.8%) who were SGA < 37. The AUC showed that the performances of the FMF2012 combined model for SGA prediction was 0.687 and for preterm SGA was 0.824. With risk cutoff of 1:150, SGA screening yielded the following: sensitivity, 47%; specificity, 75%; LR +, 1.88; PPV, 8.66%; NPV, 96.72%. When screening for preterm SGA, we found sensitivity 66.6%, specificity 74.59%, LR +: 2.58, PPV 2%, and NPV 99.63%.

CONCLUSIONS

Performance of the FMF2012 algorithm in predicting SGA in our population was similar to that obtained in the reference population, according to sensitivity, but our false positive rate is significantly higher than the reference population.

Can Fetal Growth Velocity and First Trimester Maternal Biomarkers Improve the Prediction of Small-for-Gestational Age and Adverse Neonatal Outcome?

BACKGROUND AND OBJECTIVES

The aim of this study was to evaluate the value of adding fetal growth velocity and first trimester maternal biomarkers to baseline screening, for the prediction of small-for-gestational age (SGA) and adverse neonatal outcomes.

METHOD

A retrospective cohort study was conducted of singleton pregnancies in the Maastricht University Medical Centre between 2012 and 2016. The biomarkers PAPP-A, β-hCG, PlGF, and sFlt-1 were measured at 11-13 weeks of gestational age (GA) and two fetal growth scans were performed (18-22 and 30-34 weeks of GA). Differences in biomarkers and growth velocities were compared between appropriate-for-gestational age (AGA; birth weight percentile 10-90) and SGA (birth weight percentile <10). Combinations of the biomarkers and fetal growth velocity were added to baseline screening for the prediction of SGA and adverse neonatal outcome.

RESULTS

We included 296 singleton pregnancies. Compared to AGA (n = 251), SGA neonates (n = 45) had significantly lower growth velocities in the abdominal circumference (mm/week): 10.1 ± 0.98 versus 10.8 ± 0.98, p = 0.001. Compared with AGA, the SGA neonates had higher sFlt-1 multiples of the median (MoM): 0.89 (0.55) versus 0.76 (0.44), p = 0.023, and a higher sFlt-1/PlGF MoM ratio: 1.09 (1.03) versus 0.90 (0.64), p = 0.027. For a 15% false-positive rate, the prediction of SGA neonates increased from 44.8% for the baseline screening model to 56.5% after the addition of fetal growth velocities, and to 73.9% after the further addition of maternal biomarkers (PPV 9.6%, NPV 82.4%). The corresponding AUC for the three models were 0.722, 0.804, and 0.839, respectively. In addition, AGA neonates with reduced fetal growth velocity had more adverse neonatal outcomes compared to the AGA reference group (12.4 vs. 3.9%, p = 0.013).

CONCLUSIONS

Combining fetal growth velocity with first trimester biomarkers resulted in a better prediction of SGA compared to baseline screening parameters alone. This approach could possibly result in reduced adverse neonatal outcomes in neonates, who are at a potential risk due to late mild placental dysfunction.

Early low molecular weight heparin for postpartum hemorrhage in women with pre-eclampsia. Is it effective to prevent consumptive coagulopathy?

Background: Postpartum hemorrhage has been one of the most common cause of maternal morbidity and mortality. An association between pre-eclampsia (PE) and postpartum hemorrhage has been shown in previous studies. The aim of this study was to compare some characteristics of postpartum hemorrhage between women with and without PE.Methods: Some characteristics of postpartum hemorrhage were compared between women with (n = 34) and without PE (n = 34). Majority of the cases underwent low molecular heparin administration at postpartum eighth hour, however, in cases who did not give satisfactory responses to blood product transfusions, to block suspected disseminated intravascular coagulation (DIC) secondary to the PE induced vascular injury, low molecular weight heparins were started within 2 h of postpartum hemorrhage. Some characteristics of cases with and without PE and with and without early low molecular weight heparin administration were compared.Results: There were five cases who needed massive transfusions in group with PE, conversely, no case required massive transfusion in group without PE (p < .05), in these five cases prophylactic dose low molecular weight heparin was started within 2 h of postpartum period, these cases determined according to the changes in hematocrit, platelet, and fibrinogen levels with corresponding transfusions. Mean systolic and diastolic blood pressures were significantly higher in PE group. Highest lactate dehydrogenase (LDH) level during follow up was significantly higher in group with PE. Mean numbers of erythrocyte, thrombocyte, and fibrinogen transfusions were significantly higher in PE group. Duration of hospital stay was also significantly higher in group with PE.Conclusions: Postpartum hemorrhage in women with PE may be resistant to blood product transfusions due to DIC and vicious cycle can be blocked by early low molecular weight heparin administration.

The profiles of soluble adhesion molecules in the "great obstetrical syndromes". J Matern Fetal Neonatal Med 2018;32:2113-2136. [PMID: 29320948 DOI: 10.1080/14767058.2018.1427058]

OBJECTIVE

The objective of this study was to determine the profiles of maternal plasma soluble adhesion molecules in patients with preeclampsia, small-for-gestational-age (SGA) fetuses, acute pyelonephritis, preterm labor with intact membranes (PTL), preterm prelabor rupture of the membranes (preterm PROM), and fetal death.

MATERIALS AND METHODS

A cross-sectional study was conducted to determine maternal plasma concentrations of sE-selectin, sL-selectin, and sP-selectin as well as sICAM-1, sVCAM-1, and sPECAM-1 in patients with (1) an uncomplicated pregnancy (control, n = 100); (2) preeclampsia (n = 94); (3) SGA fetuses (in women without preeclampsia/hypertension, n = 45); (4) acute pyelonephritis (n = 25); (5) PTL (n = 53); (6) preterm PROM (n = 24); and (7) fetal death (n = 34). Concentrations of soluble adhesion molecules and inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-8) were determined with sensitive and specific enzyme-linked immunoassays.

RESULTS

In comparison to women with a normal pregnancy, (1) women with preeclampsia had higher median concentrations of sE-selectin, sP-selectin, and sVCAM-1, and a lower concentration of sL-selectin (all p values < .001); (2) patients with SGA fetuses had higher median concentrations of sE-selectin, sP-selectin, and sVCAM-1 (all p values < .05); (3) patients with a fetal death had higher median concentrations of sE-selectin and sP-selectin (all p values < .05); (4) patients with acute pyelonephritis had higher median plasma concentrations of sE-selectin, sICAM-1, and sVCAM-1 (all p values < .001); (5) patients with preeclampsia and acute pyelonephritis, plasma concentrations of sVCAM-1, sE-selectin, and sP-selectin correlated with those of the proinflammatory cytokines TNF-α and interleukin (IL)-8 (all p values < .05); (6) patients with PTL had a higher median concentration of sP-selectin and a lower median concentration of VCAM-1 (all p values < .05); and (7) women with preterm PROM had lower median concentrations of sL-selectin and sVCAM-1 (all p values < .05).

CONCLUSIONS

The results of this study show that endothelial cell activation/dysfunction reflected by the plasma concentration of sE-selectin is not specific to preeclampsia but is present in pregnancies complicated by SGA fetuses, acute pyelonephritis, and fetal death. Collectively, we report that each obstetrical syndrome appears to have a stereotypical profile of soluble adhesion molecules in the peripheral circulation.

Validation of Fetal Medicine Foundation algorithm for prediction of pre-eclampsia in the first trimester in an unselected Brazilian population

OBJECTIVE

The objective of this study is to evaluate the predictive performance of the Fetal Medicine Foundation (FMF) algorithm for prediction of preeclampsia (PE) between 11 and 14 weeks of gestation in an unselected Brazilian population.

METHODS

We conducted a prospective cohort study with 617 singleton pregnancies of unselected risk. Biophysical markers (mean pulsatility index, mean arterial pressure) and biochemical markers (placental growth factor (PLGF) and PAPP-A) were inserted into the FMF software and converted into multiples of the median (MoM). The subjects were divided into five groups: early-onset PE, parturition <34 weeks' gestation; preterm PE, parturition <37 weeks; PE, parturition at any gestational age; gestational hypertension (GH); and control group. Areas under the receiver operating characteristics curve (AUC) were calculated for the outcomes.

RESULTS

Among 617 patients, seven developed early-onset PE, 18 developed preterm PE (seven early PE plus 11 delivered between 34 and 36 + 6 weeks gestation), 34 developed PE (18 preterm PE plus 16 delivered after 37-week gestation), 12 pregnant women developed GH, and 517 women comprised the control group. The best predictive performance using the FMF algorithm occurred in the early-onset PE group, with AUC = 0.946 (95% CI 0.919-0.973) and the detection rate of 28.6% and 85.7% for 5% and 10% false-positive (FP), respectively.

CONCLUSIONS

The FMF algorithm to predict PE was effective in a Brazilian population, mainly in the early-onset form of the disease at 10% FP.

Assessment of Serum Vascular Endothelial Growth Factor Levels in Pregnancy-Induced Hypertension Patients

Objective. The objective of the study was to assess the serum vascular endothelial growth factor (VEGF) levels in peripheral blood of patients with pregnancy-induced hypertension (PIH) and find association between serum VEGF levels and PIH. Methods. Thirty-five PIH subjects, 35 normal pregnant females, and 20 normal healthy females were included in the study. Detailed history, clinical examination, and relevant biochemical parameters were assessed; serum VEGF levels were estimated using Double-antibody enzyme-linked immunosorbent assay. Results. The study groups were found to be age matched (p = 0.38). VEGF level in the pregnancy-induced hypertensive group (median = 109.19 (3.38 ± 619)) was significantly higher than the normal pregnant (median = 20.82 (1.7-619)) and control (median = 4.92 (1.13-13.07)) group and the difference between these three groups was significant (p < 0.0001). The 3 groups are found to be significantly different in terms of RBS (p = 0.01), urea (p < 0.0001), creatinine (p = 0.0005), AST (p = 0.0032), ALT (p = 0.0007), total protein (p = 0.0004), albumin (p < 0.0001), calcium (p = 0.001), and sodium (p = 0.02), while no statistically significant difference was found between total bilirubin (p = 0.167), direct bilirubin (p = 0.07), uric acid (p = 0.16), and potassium (p = 0.14). Conclusion. Significantly higher levels of serum VEGF were noted in PIH subjects compared to normal pregnant and control subjects.

Establishment of the Human Uteroplacental Circulation: A Historical Perspective

The uterine vasculature undergoes marked changes during pregnancy in order to provide the necessary increase in blood flow to support growth and nutrition of the uterus, placenta, and developing fetus. Pregnancy-associated uterine vascular transformations are orchestrated by a complex array of endocrine and cellular mechanisms to bring about structural modifications at the maternal-fetal interface, which collectively lead to development of the uteroplacental circulation. Understanding intrinsic uterine vascular remodeling in pregnancy is essential for understanding the physiologic and pathophysiologic regulation of maternal uterine blood flow. Aberrations of uterine vascular remodeling are potentially involved in the etiology of several pregnancy disorders, for example, preeclampsia, fetal growth restriction, and preterm labor; therefore, it is essential for subspecialist clinicians and investigators interested in reproductive physiology to fully understand the establishment of uteroplacental circulation. The foundational literature in this area is extensive; thus, a succinct review is likely to be a useful resource. Herein, we present and discuss a historical perspective on uterine vascular anatomy, maternal vascular growth associated with decidualization, trophoblast invasion, intervillous circulation, aberrations in uterine vascular modeling, and the clinical implications of improper development of the uteroplacental circulation.

Maternal plasma angiogenic index-1 (placental growth factor/soluble vascular endothelial growth factor receptor-1) is a biomarker for the burden of placental lesions consistent with uteroplacental underperfusion: a longitudinal case-cohort study

BACKGROUND

Placental lesions consistent with maternal vascular underperfusion (MVU) are thought to be pathogenically linked to preeclampsia, small-for-gestational-age newborns, fetal death, and spontaneous preterm labor and delivery; yet, these lesions cannot be diagnosed antenatally. We previously reported that patients with such conditions and lesions have an abnormal profile of the angiogenic placental growth factor (PlGF) and antiangiogenic factors (eg, soluble vascular endothelial growth factor receptor [sVEGFR]-1).

OBJECTIVE

The objectives of this study were to: (1) examine the relationship between the maternal plasma PlGF/sVEGFR-1 concentration ratio (referred to herein as angiogenic index-1) and the burden of histologic placental features consistent with MVU; and (2) test the hypothesis that angiogenic index-1 can identify patients in the midtrimester who are destined to deliver before 34 weeks of gestation with multiple (ie, ≥3) histologic placental features consistent with MVU.

STUDY DESIGN

A 2-stage case-cohort sampling strategy was used to select participants from among 4006 women with singleton gestations enrolled from 2006 through 2010 in a longitudinal study. Maternal plasma angiogenic index-1 ratios were determined using enzyme-linked immunosorbent assays. Placentas underwent histologic examination according to standardized protocols by experienced pediatric pathologists who were blinded to clinical diagnoses and pregnancy outcomes. The diagnosis of lesions consistent with MVU was made using criteria proposed by the Perinatal Section of the Society for Pediatric Pathology. Weighted analyses were performed to reflect the parent cohort; "n*" is used to reflect weighted frequencies.

RESULTS

(1) Angiogenic index-1 (PlGF/sVEGFR-1) concentration ratios were determined in 7560 plasma samples collected from 1499 study participants; (2) the prevalence of lesions consistent with MVU was 21% (n* = 833.9/3904) and 27% (n* = 11.4/42.7) of women with ≥3 MVU lesions delivered before 34 weeks of gestation; (3) a low angiogenic index-1 (<2.5th quantile for gestational age) in maternal plasma samples obtained within 48 hours of delivery had a sensitivity of 73% (n* = 8.3/11.4; 95% confidence interval [CI], 47-98%), a specificity of 94% (n* = 3130.9/3316.2; 95% CI, 94-95%), a positive likelihood ratio of 12.2, and a negative likelihood ratio of 0.29 in the identification of patients who delivered placentas with ≥3 MVU lesions at <34 weeks; (4) prospectively, at 20-23 weeks of gestation, a maternal plasma concentration of angiogenic index-1 <2.5th quantile identified 70% (n* = 7.2/10.3; 95% CI, 42-98%) of patients who delivered placentas with ≥3 MVU lesions before 34 weeks (specificity, 97% [n* = 2831.3/2918; 95% CI, 96-98%]; positive likelihood ratio, 23; negative likelihood ratio, 0.31); and (5) among women without obstetrical complications who delivered at term, angiogenic index-1 was lower in women with than without placental lesions consistent with MVU (P < .05).

CONCLUSION

Maternal plasma angiogenic index-1 (PlGF/sVEGFR-1) is the first biomarker for the burden of placental lesions consistent with MVU. We propose that an accumulation of these lesions in placentas delivered before 34 weeks is a histologic counterpart of an antiangiogenic profile.

Oxidative Stress: Placenta Function and Dysfunction

During pregnancy, the placenta is a site of active oxygen metabolism that continuously generates oxidative stress (OS). Overproduction of reactive oxygen species and reactive nitrogen species can destroy normal placental functions. Therefore, the feto-placental unit generates abundant antioxidants to keep OS under control. Properly controlled oxidative species have been proven to serve as indispensable cellular signal messengers by regulating gene expression and downstream cellular activities. OS also plays an important immunoregulatory role during pregnancy. Oxidative disorder and immune disturbances are associated with adverse pregnancy outcomes such as spontaneous abortion, preeclampsia and intrauterine growth restriction. In this review, we introduce recent studies revealing basal functions and regulatory roles of placental OS in metabolism and immunity. The relationships between OS- and pregnancy-related disorders are also discussed.

Acute atherosis in vacuum suction biopsies of decidua basalis: An evidence based research definition

BACKGROUND

Acute atherosis (AA) of the uteroplacental spiral arteries has been characterised by subendothelial lipid-laden foam cells, perivascular leukocyte infiltrates (PVI) and fibrinoid necrosis. Because precise diagnostic criteria are not available for comparative research studies we developed and tested new simplified criteria based on 237 cases.

METHODS

Decidual basalis samples were collected by vacuum suction at elective cesarean deliveries. Spiral arteries were evaluated in serial decidual tissue sections from women with normal pregnancy, preeclampsia, and diabetes. Features of AA were sought in parallel sections stained with H&E and immunostained for CD68, cytokeratin CK7 and desmin, and costained with Periodic Acid Schiff (PAS).

RESULTS

Foam cell lesions were defined as two or more adjacent, intramural, vacuolated CD68 positive cells, PVI as a focal perivascular lymphocyte accumulation, more dense than in the surrounding decidua. Increased fibrinoid (PAS positive) was identified if present in ≥75% of the arterial wall circumference. PVI and increased fibrinoid were significantly associated with preeclampsia but not specifically associated with the presence of foam cell lesions. Hence we diagnosed decidua basalis AA lesions solely by the presence of foam cell lesions, occurring in preeclampsia (37%), diabetes (10%) and healthy normotensive women (11%). The simplified criterion was reproducible by different investigators. Decidua basalis AA occurred most commonly and extensively in preeclampsia, but did not distinguish between preterm and term disease.

DISCUSSION

Our evidence based criterion for decidua basalis AA diagnosis in vacuum suction biopsies may not apply to myometrial or decidua parietalis arteries. In decidual basalis samples it should facilitate comparisons between research studies, to improve pathophysiological understanding of AA and preeclampsia.

Acute Atherosis of the Uterine Spiral Arteries: Clinicopathologic Implications

Acute atherosis is unique vascular changes of the placenta associated with poor placentation. It is characterized by subendothelial lipid-filled foam cells, fibrinoid necrosis of the arterial wall, perivascular lymphocytic infiltration, and it is histologically similar to early-stage atherosclerosis. Acute atherosis is rare in normal pregnancies, but is frequently observed in non- transformed spiral arteries in abnormal pregnancies, such as preeclampsia, small for gestational age (SGA), fetal death, spontaneous preterm labor and preterm premature rupture of membranes. In preeclampsia, spiral arteries fail to develop physiologic transformation and retain thick walls and a narrow lumen. Failure of physiologic transformation of spiral arteries is believed to be the main cause of uteroplacental ischemia, which can lead to the production of anti-angiogenic factors and induce endothelial dysfunction and eventually predispose the pregnancy to preeclampsia. Acute atherosis is more frequently observed in the spiral arteries of the decidua of the placenta (parietalis or basalis) than in the decidual or myometrial segments of the placental bed. The presence and deeper location of acute atherosis is associated with poorer pregnancy outcomes, more severe disease, earlier onset of preeclampsia, and a greater frequency of SGA neonates in patients with preeclampsia. Moreover, the idea that the presence of acute atherosis in the placenta may increase the risk of future cardiovascular disease in women with a history of preeclampsia is of growing concern. Therefore, placental examination is crucial for retrospective investigation of pregnancy complications and outcomes, and accurate placental pathology based on universal diagnostic criteria in patients with abnormal pregnancies is essential for clinicopathologic correlation.

Prediction of small-for-gestational-age neonates: screening by uterine artery Doppler and mean arterial pressure at 30-34 weeks

OBJECTIVE

To investigate the potential value of uterine artery (UtA) pulsatility index (PI) and mean arterial pressure (MAP) at 30-34 weeks' gestation in the prediction of small-for-gestational-age (SGA) neonates, in the absence of pre-eclampsia (PE).

METHODS

This was a screening study in singleton pregnancies at 30-34 weeks' gestation, including 1727 that delivered SGA neonates with a birth weight < 5(th) percentile and 29 122 that were unaffected by SGA, PE or gestational hypertension (normal group). Multivariable logistic regression analysis was used to determine if measuring the UtA-PI and MAP improved the prediction of SGA neonates provided by screening with maternal characteristics and medical history (maternal factors), and estimated fetal weight (EFW) calculated from fetal head circumference, abdominal circumference and femur length.

RESULTS

Combined screening by maternal factors and EFW Z-scores predicted 79%, 87% and 92% of SGA neonates delivering < 5 weeks following assessment, with a birth weight < 10(th) , < 5(th) and < 3(rd) percentiles, respectively, at a false-positive rate of 10%. The addition of UtA-PI and MAP improved the respective detection rates to 83%, 91% and 93%. Screening by maternal factors and EFW Z-scores predicted 53%, 58% and 61% of SGA delivering ≥ 5 weeks following assessment and these rates increased to 53%, 60% and 63% with the addition of UtA-PI and MAP.

CONCLUSION

Combined testing by maternal factors, fetal biometry, UtA-PI and MAP at 30-34 weeks' gestation could identify a high proportion of pregnancies that deliver SGA neonates.

Protective effect of (±)α-tocopherol on brominated diphenyl ether-47-stimulated prostaglandin pathways in human extravillous trophoblasts in vitro

Brominated diphenyl ether (BDE)-47 is a prevalent flame retardant chemical found in human tissues and is linked to adverse pregnancy outcomes in humans. Because dysregulation of the prostaglandin pathway is implicated in adverse pregnancy outcomes, the present study investigates BDE-47 induction of prostaglandin synthesis in a human extravillous trophoblast cell line, HTR-8/SVneo, examining the hypothesis that BDE-47 increases generation of reactive oxygen species (ROS) to stimulate the prostaglandin response. Treatment with 20 μM BDE-47 significantly increased mRNA expression of prostaglandin-endoperoxide synthase 2 (PTGS2) at 4, 12 and 24 h, and 24-h treatment significantly increased cyclooxygenase (COX)-2 cellular protein expression and prostaglandin E2 (PGE2) concentration in culture medium. The BDE-47-stimulated PGE2 release was inhibited by the COX inhibitors indomethacin and NS398, implicating COX activity. Exposure to 20 μM BDE-47 significantly increased ROS generation as measured by carboxydichlorofluorescein fluorescence, and this response was blocked by cotreatment with the peroxyl radical scavenger (±)-α-tocopherol. (±)-α-Tocopherol cotreatment suppressed BDE-47-stimulated increases of PGE2 release without significant effects on COX-2 mRNA and protein expression, implicating a role for ROS in post-translational regulation of COX activity. Because prostaglandins regulate trophoblast functions necessary for placentation and pregnancy, further investigation is warranted of BDE-47 impacts on trophoblast responses.

The frequency of acute atherosis in normal pregnancy and preterm labor, preeclampsia, small-for-gestational age, fetal death and midtrimester spontaneous abortion

OBJECTIVE

Acute atherosis is characterized by subendothelial lipid-filled foam cells, fibrinoid necrosis and perivascular lymphocytic infiltration. This lesion is generally confined to non-transformed spiral arteries and is frequently observed in patients with preeclampsia. However, the frequency of acute atherosis in the great obstetrical syndromes is unknown. The purpose of this study was to determine the frequency and topographic distribution of acute atherosis in placentas and placental bed biopsy samples obtained from women with normal pregnancy and those affected by the "great obstetrical syndromes". We also examined the relationship between acute atherosis and pregnancy outcome in patients with preeclampsia.

MATERIAL AND METHODS

A retrospective cohort study of pregnant women who delivered between July 1998 and July 2014 at Hutzel Women's Hospital/Detroit Medical Center was conducted to examine 16, 345 placentas. Patients were classified into the following groups: (1) uncomplicated pregnancy; (2) spontaneous preterm labor (sPTL) and preterm prelabor rupture of membranes (PPROM); (3) preeclampsia; (4) gestational hypertension; (5) small-for-gestational age (SGA); (6) chronic hypertension; (5) fetal death; (6) spontaneous abortion and (7) others. A subset of patients had placental bed biopsy. The incidence of acute atherosis was compared among the different groups.

RESULTS

(1) The prevalence of acute atherosis in uncomplicated pregnancies was 0.4% (29/6961) based upon examination of nearly 7000 placentas; (2) the frequency of acute atherosis was 10.2% (181/1779) in preeclampsia, 9% (26/292) in fetal death, 2.5% (3/120) in midtrimester spontaneous abortion, 1.7% (22/1,298) in SGA neonates and 1.2% (23/1,841) in sPTL and PPROM; (3) among patients with preeclampsia, those with acute atherosis than in those without the lesion had significantly more severe disease, earlier onset, and a greater frequency of SGA neonates (p < 0.05 all) and (4) the lesion was more frequently observed in the decidua (parietalis or basalis) than in the decidual segment of the spiral arteries in patients with placental bed biopsies.

CONCLUSIONS

Acute atherosis is rare in normal pregnancy, and occurs more frequently in patients with pregnancy complications, including preeclampsia, sPTL, preterm PROM, midtrimester spontaneous abortion, fetal death and SGA.

Placental lesions associated with acute atherosis

OBJECTIVE

Acute atherosis is a lesion of the spiral arteries characterized by fibrinoid necrosis of the vessel wall, an accumulation of fat-containing macrophages, and a mononuclear perivascular infiltrate, which can be found in patients with preeclampsia, fetal death, small-for-gestational age, spontaneous preterm labor/premature prelabor rupture of membrane, and spontaneous mid-trimester abortion. This lesion is thought to decrease blood flow to the intervillous space which may lead to other vascular lesions of the placenta. The objective of this study was to test whether there is an association between acute atherosis and placental lesions that are consistent with maternal vascular underperfusion (MVU), amniotic fluid infection (AFI), fetal vascular thrombo-occlusive disease (FVTOD) or chronic inflammation.

MATERIAL AND METHODS

A retrospective cohort study of pregnant women who delivered between July 1998 and July 2014 at Hutzel Women's Hospital/Detroit Medical Center was conducted examine 16 457 placentas. The frequency of placenta lesions (diagnosed using the criteria of the Perinatal Section of the Society for Pediatric Pathology) was compared between pregnancies with and without acute atherosis.

RESULTS

Among 16 457 women who were enrolled, 10.2% (1671/16 457) were excluded, leaving 14 786 women who contributed data for analysis. Among them, the prevalence of acute atherosis was 2.2% (326/14 786). Women with acute atherosis were more than six times as likely as those without to have placental lesions consistent with maternal underperfusion (adjusted odds ratio - aOR: 6.7; 95% CI 5.2-8.6). To a lesser degree, acute atherosis was also associated with greater risks of having either lesions consistent with FVTOD (aOR 1.7; 95% CI 1.2-2.3) or chronic chorioamnionitis (aOR 1.9; 95% CI 1.3-3), but not with other chronic inflammatory lesions, after adjusting for gestational age at delivery. In contrast, women with acute atherosis were 60% less likely to have lesions consistent with AFI, adjusting for gestational age at delivery (aOR 0.4; 95% CI 0.3-0.5).

CONCLUSIONS

Acute atherosis is associated with increased risks of having placental lesions consistent with MVU, and to a lesser extent, chronic chorioamnionitis and those consistent with FVTOD.

Antiphospholipid antibodies and the placenta: a systematic review of their in vitro effects and modulation by treatment

BACKGROUND

Antiphospholipid antibodies (aPL) are a family of auto-antibodies that are associated with an increased risk of recurrent miscarriage, intrauterine growth restriction and preterm birth. The placenta is a major target of aPL and it is likely that these antibodies promote pregnancy morbidity by affecting trophoblast function. Numerous studies have investigated the effect of aPL on trophoblast function in vitro. However, different trophoblast models and a variety of culture conditions have been employed, resulting in a myriad of different reported findings. This review systematically summarized those published studies that have investigated the effect of aPL on trophoblast function in vitro. In addition, the reported effects of pharmacological treatment on trophoblast function in the presence of aPL were also systematically reviewed.

METHODS

PubMed, Scopus, Embase and Web of Science databases were searched using the keywords 'placenta OR trophoblast' AND 'antiphospholipid antibody OR antiphospholipid syndrome' up to 25 April 2014. Studies were excluded based on the absence of appropriate controls. The effects of aPL on trophoblast proliferation, death, syncytialization, invasion, hormone production, cytokine production, coagulation and complement activation were recorded. The effects of different treatments on the function of trophoblasts in the presence of aPL were also recorded.

RESULTS

A total of 1071 records were retrieved from the four databases. After removing duplicates, the titles and abstracts of 529 articles were reviewed. Of those, 48 articles were read and relevant experimental results were extracted from 47 articles.

CONCLUSIONS

This systematic review provides an overview of all the studies performed to date on the effects of aPL on trophoblast function in vitro. There is considerable support for aPL decreasing trophoblast viability, syncytialization and invasion in vitro. Some work has also suggested that aPL may affect the production of hormones and signalling molecules by trophoblasts, and may stimulate coagulation and complement activation in vitro. Current reports of the in vitro effects of therapeutic treatments on trophoblast function in the presence of aPL are inconclusive. This systematic review has highlighted many gaps in our knowledge of how aPL work and may direct future research in this area.

Hypoxia and the anticoagulants dalteparin and acetylsalicylic acid affect human placental amino acid transport

Background

Anticoagulants, e.g. low-molecular weight heparins (LMWHs) and acetylsalicylic acid (ASA) are prescribed to women at risk for pregnancy complications that are associated with impaired placentation and placental hypoxia. Beyond their role as anticoagulants these compounds exhibit direct effects on trophoblast but their impact on placental function is unknown. The amino acid transport systems A and L, which preferably transfer essential amino acids, are well-described models to study placental nutrient transport. We aimed to examine the effect of hypoxia, LMWHs and ASA on the activity of the placental amino acid transport systems A and L and associated signalling mechanisms.

Methods

The uptake of C¹⁴-MeAIB (system A) or H³-leucin (system L) was investigated after incubation of primary villous fragments isolated from term placentas. Villous tissue was incubated at 2% O₂ (hypoxia), 8% O₂ and standard culture conditions (21% O₂) or at 2% O₂ and 21% O₂ with dalteparin or ASA. Activation of the JAK/STAT or mTOR signalling pathways was determined by Western analysis of total and phosphorylated STAT3 or Raptor.

Results

Hypoxia decreased system A mediated MeAIB uptake and increased system L mediated leucine uptake compared to standard culture conditions (21% O₂). This was accompanied by an impairment of STAT3 and a stimulation of Raptor signalling. System L activity increased at 8% O₂. Dalteparin treatment reduced system A and system L activity under normoxic conditions and ASA (1 mM) decreased system A and L transporter activity under normoxic and hypoxic conditions.

Conclusions

Our data underline the dependency of placental function on oxygen supply. LMWHs and ASA are not able to reverse the effects of hypoxia on placental amino acid transport. These findings and the uncovering of the signalling mechanisms in more detail will help to understand the impact of LMWHs and ASA on placental function and fetal growth.

The anti-aging factor α-klotho during human pregnancy and its expression in pregnancies complicated by small-for-gestational-age neonates and/or preeclampsia

OBJECTIVE

α-klotho, a protein with anti-aging properties, has been involved in important biological processes, such as calcium/phosphate metabolism, resistance to oxidative stress, and nitric oxide production in the endothelium. Recent studies have suggested a role of α-klotho in endocrine regulation of mineral metabolism and postnatal growth in infants. Yet, the role of α-klotho during pregnancy remains largely unknown. The aim of this study was to determine whether maternal plasma concentration of α-klotho changes during pregnancy and evaluate its expression in pregnancies complicated by small for gestational age (SGA) and/or preeclampsia (PE).

STUDY DESIGN

This cross-sectional study included patients in the following groups: (1) non pregnant women (n = 37); (2) uncomplicated pregnancy (n = 130); (3) PE without an SGA neonate (PE; n = 58); (4) PE with an SGA neonate (PE and SGA; n = 52); and (5) SGA neonate without PE (SGA; n = 52). Plasma concentrations of α-klotho were determined by ELISA.

RESULTS

The median plasma α-klotho concentration was higher in pregnant than in non-pregnant women. Among women with an uncomplicated pregnancy, the median plasma concentration of α-klotho increased as a function of gestational age (Spearman Rho = 0.2; p = 0.006). The median (interquartile range) plasma concentration of α-klotho in women with PE and SGA [947.6 (762-2013) pg/mL] and SGA without PE [1000 (585-1567) pg/mL] were 21% and 17% lower than that observed in women with an uncomplicated pregnancy [1206.6 (894-2012) pg/mL], (p = 0.005 and p = 0.02), respectively. Additionally, there were no significant differences in the median plasma concentration of α-klotho between uncomplicated pregnancies and women with PE without an SGA neonate (p = 0.5).

CONCLUSION

Maternal plasma concentration of α-klotho was higher during pregnancy than in a non-pregnant state. Moreover, the median maternal plasma concentration of α-klotho was lower in mothers who delivered an SGA neonate than in those with an uncomplicated pregnancy regardless of the presence or absence of PE.

Elevated maternal serum sP-selectin levels in preeclamptic pregnancies with and without intrauterine fetal growth restriction, but not in normotensive pregnancies complicated by isolated IUGR

Background

The aim of this study was to show differences of maternal serum sP-selectin levels in pregnancies complicated by intrauterine fetal growth restriction (IUGR) in the course of preeclampsia and to compare the results with normotensive pregnant women with isolated IUGR. These studies were also conducted on preeclamptic pregnancies with appropriate-for-gestational-age weight infants and on the control normotensive pregnant women.

Material/Methods

The study was carried out on 55 patients with pregnancy complicated by fetal growth restriction in the course of preeclampsia, 70 normotensive patients with pregnancies complicated by isolated IUGR, 39 preeclamptic patients with appropriate-for-gestational-age weight fetuses and 54 healthy normotensive pregnant patients with normal fetal growth. Maternal serum levels of sP-selectin were determined using the enzyme-linked immunosorbent assay.

Results

Levels of sP-selectin were higher in women with pregnancy complicated by preeclampsia with and without IUGR; whereas, in the group of normotensive pregnant women with isolated fetal growth restriction, serum sP-selectin levels tended to be lower than in the control subjects, but this difference was not statistically significant. The mean values were 192.05±70.96 ng/mL in the IUGR group, 293.18±222.92 ng/mL in the PI group, 379.78±353.13 ng/mL in the P group and 227.96±134.04 ng/mL in the healthy controls (p<0.001*).

Conclusions

Our findings may suggest that the elevated level of the soluble P-selectin is associated with preeclampsia, and that it may confirm the presence of platelet and endothelial activation, the presence of the hypercoagulant state and may be due to the systemic inflammatory response in this serious pregnancy disorder.

Perfusion with magnesium sulfate increases sFlt-1 secretion only in the fetal side of placenta of women with preeclampsia

OBJECTIVE

To examine the effect of magnesium sulfate (MgSO(4)) on sFlt (soluble fms-like tyrosine kinase)-1 in the fetal and maternal compartments of normotensive and preeclamptic placentas.

METHODS

Cotyledons of term normotensive and preeclamptic placentas were dually perfused for six hours, with control medium and MgSO(4) (6-7 mg %) in the maternal reservoir. Perfusate sFlt-1 concentrations were measured.

RESULTS

Median sFlt-1 concentration was higher in the maternal than in the fetal side in both groups and perfusion media (p < 0.0001). When perfused with control medium, the maternal side median sFlt-1 concentration was higher in the preeclampsia than in the control group (p < 0.0001). After perfusion with MgSO(4), the median maternal and fetal sides perfusate sFlt-1 concentration were higher in the preeclampsia than in the control group (p < 0.0001). In comparison to perfusion with control medium, the median sFlt-1 concentration of normal pregnant women decreased in the fetal and increased in the maternal side. In the preeclampsia group, only median fetal side sFlt-1 concentration increased.

CONCLUSION

In contrast to normal pregnant women, perfusion with MgSO(4) of preeclamptic placentas did not increase their sFlt-1 concentration. This may indicate that MgSO(4) role may be limited to its anti-eclamptic and does not affect the anti-angiogenic state associated with preeclampsia.

Beyond the placental bed: placental and systemic determinants of the uterine artery Doppler waveform

The uterine artery Doppler waveform has been extensively investigated, though its widespread clinical use as a predictor of adverse pregnancy outcome remains under debate. The determinants of the waveform have classically been ascribed to transformation of the spiral arteries and the development of a low resistance uteroplacental circulation, failure of which predisposes to pre-eclampsia, fetal growth restriction and other adverse outcomes. It has become increasingly evident that although spiral artery transformation determines in some part the characteristics of the Doppler waveform, factors pertaining to maternal vascular and endothelial function are also important.

The role of homeobox genes in the development of placental insufficiency

Intrauterine growth restriction (IUGR) is an adverse pregnancy outcome associated with significant perinatal and pediatric morbidity and mortality, and an increased risk of chronic disease later in adult life. While a number of maternal, fetal and environmental factors are known causes of IUGR, the majority of IUGR cases are of unknown cause. These IUGR cases are frequently associated with placental insufficiency, possibly as a result of placental maldevelopment. Understanding the molecular mechanisms of abnormal placental development in IUGR associated with placental insufficiency is therefore of increasing importance. Here, we review our understanding of transcriptional control of normal placental development as well as human IUGR associated with placental insufficiency. We also assess the potential for understanding transcriptional control as a means for revealing new molecular targets for the detection, diagnosis and clinical management of IUGR associated with placental insufficiency.

The placenta in preeclampsia

The root cause of preeclampsia is the placenta. Preeclampsia begins to abate with the delivery of the placenta and can occur in the absence of a fetus but with the presence of trophoblast tissue with hydatidiform moles. In view of this, study of the placenta should provide insight into the pathophysiology of preeclampsia. In this presentation we examine placental pathological and pathophysiological changes with preeclampsia and fetal growth restriction (FGR). It would seem that this comparison should be illuminating as both conditions are associated with similarly abnormal placentation yet only in preeclampsia is there a maternal pathophysiological syndrome. Similar insights about early and late onset preeclampsia should also be provided by such information.We report that the placental abnormalities in preeclampsia are what would be predicted in a setting of reduced perfusion and oxidative stress. However, the differences from FGR are inconsistent. The most striking differences between the two conditions are found in areas that have been the least studied. There are differences between the placental findings in early and late onset preeclampsia but whether these are qualitative, indicating different diseases, or simply quantitative differences within the same disease is difficult to determine.We attempt to decipher the true differences, seek an explanation for the disparate results and provide recommendations that we hope may help resolve these issues in future studies.

VTE, thrombophilia, antithrombotic therapy, and pregnancy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

The use of anticoagulant therapy during pregnancy is challenging because of the potential for both fetal and maternal complications. This guideline focuses on the management of VTE and thrombophilia as well as the use of antithrombotic agents during pregnancy.

METHODS

The methods of this guideline follow the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.

RESULTS

We recommend low-molecular-weight heparin for the prevention and treatment of VTE in pregnant women instead of unfractionated heparin (Grade 1B). For pregnant women with acute VTE, we suggest that anticoagulants be continued for at least 6 weeks postpartum (for a minimum duration of therapy of 3 months) compared with shorter durations of treatment (Grade 2C). For women who fulfill the laboratory criteria for antiphospholipid antibody (APLA) syndrome and meet the clinical APLA criteria based on a history of three or more pregnancy losses, we recommend antepartum administration of prophylactic or intermediate-dose unfractionated heparin or prophylactic low-molecular-weight heparin combined with low-dose aspirin (75-100 mg/d) over no treatment (Grade 1B). For women with inherited thrombophilia and a history of pregnancy complications, we suggest not to use antithrombotic prophylaxis (Grade 2C). For women with two or more miscarriages but without APLA or thrombophilia, we recommend against antithrombotic prophylaxis (Grade 1B).

CONCLUSIONS

Most recommendations in this guideline are based on observational studies and extrapolation from other populations. There is an urgent need for appropriately designed studies in this population.

Preeclampsia, hypoxia, thrombosis, and inflammation

Reductions in uteroplacental flow initiate a cascade of molecular effects leading to hypoxia, thrombosis, inflammation, and endothelial cell dysfunction resulting in untoward pregnancy outcomes. In this review, we detail these effects and their relationship to preeclampsia (PE) and intrauterine growth restriction (IUGR).

MBL interferes with endovascular trophoblast invasion in pre-eclampsia

The spiral arteries undergo physiologic changes during pregnancy, and the failure of this process may lead to a spectrum of pregnancy disorders, including pre-eclampsia. Our recent data indicate that decidual endothelial cells (DECs), covering the inner side of the spiral arteries, acquire the ability to synthesize C1q, which acts as a link between endovascular trophoblast and DECs favouring the process of vascular remodelling. In this study, we have shown that sera obtained from pre-eclamptic patients strongly inhibit the interaction between extravillous trophoblast (EVT) and DECs, preventing endovascular invasion of trophoblast cells. We further demonstrated that mannose-binding lectin (MBL), one of the factor increased in pre-eclamptic patient sera, strongly inhibits the interaction of EVT with C1q interfering with the process of EVT adhesion to and migration through DECs. These data suggest that the increased level of MBL in pre-eclampsia may contribute to the failure of the endovascular invasion of trophoblast cells.

Maternal thyroid function at eleven to thirteen weeks of gestation and subsequent delivery of small for gestational age neonates

BACKGROUND

Studies have shown that altered thyroid function in early pregnancy may affect normal placental development and hence fetal growth. Our hypothesis is that maternal thyroid function in the first trimester is altered in pregnancies that subsequently deliver small for gestational age (SGA) neonates.

METHODS

Maternal serum thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were measured at 11(+0) to 13(+6) weeks' gestation in 212 singleton pregnancies with no history of thyroid disease that subsequently delivered SGA neonates and the values were compared with the results of 3598 normal pregnancies delivering neonates with birth weight above the 5th percentile for gestation.

RESULTS

There were no significant differences between the normal and SGA groups in median multiple of the median (MoM) TSH (1.07 vs. 1.061 MoM), FT4 (0.992 vs. 1.010 MoM), and FT3 (0.991 vs. 0.990 MoM).

CONCLUSION

In women with no history of thyroid disease delivering SGA neonates, thyroid function during the first trimester of pregnancy is not significantly different from women delivering non-SGA neonates.

Endothelin: key mediator of hypertension in preeclampsia

Preeclampsia is a pregnancy-induced hypertensive disorder characterized by proteinuria and widespread maternal endothelial dysfunction. It remains one of the most common disorders in pregnancy and remains one of the leading causes of maternal and fetal morbidity. Recent research has revealed that placental insufficiency, resulting in hypoxia and ischemia, is a central causative pathway in the development of the disorder. In response, the placenta secretes soluble substances into the maternal circulation which are responsible for the symptomatic phase of the disease. Among the most well characterized factors in the disease pathology are the anti-angiogenic protein soluble fms-like tyrosine kinase-1 (sFlt-1), inflammatory cytokines, and agonistic angiotensin II type-1 receptor autoantibodies. Each of these factors has been shown to induce hypertension experimentally through the production of endothelin-1 (ET-1), a powerful vasoconstrictor. Antagonism of the endothelin-A receptor has proved beneficial in numerous animal models of gestational hypertension, and it remains an intriguing target for pharmacological intervention in preeclampsia.

Association between maternal serum cytokine profiles at 7-10 weeks' gestation and birthweight in small for gestational age infants

OBJECTIVE

The purpose of this study was to investigate whether birth of a small-for-gestational-age (SGA) baby (birthweight, <10th percentile) is preceded by altered maternal serum cytokine profiles at early pregnancy, compared with control babies (birthweight, 30-80th percentile).

STUDY DESIGN

A retrospective case-control study of maternal serum collected prospectively across 7-10 weeks of gestation from women attending their first prenatal visit (SGA, 57 cases; control subjects, 71 cases selected retrospectively). Serum concentrations of 27 cytokines were measured in each sample and analyzed by 2-way analysis of variance and nonparametric tests. Logistic regression was used for predictive modeling.

RESULTS

Of 21 detectable cytokines/chemokines, 14 analytes varied significantly (P ≤ .030) among those women who were destined to deliver an SGA baby, when compared with control subjects. Of the cytokines that varied in association with SGA, interferon-γ concentrations increased, and major proinflammatory (interleukin [IL]-2, -7, -12) and antiinflammatory (IL-1 receptor antagonist, -4, -10, -13) cytokine concentrations decreased. Eotaxin and macrophage inflammatory protein-1α were higher; monocyte chemoattractant protein-1 and IL-8 were lower.

CONCLUSION

SGA births may be preceded by altered immune cytokine profiles at 7-10 weeks of gestation.