Obesity in pregnancy causes a volume overload in third trimester

Maternal Cardiac Function in Pregnancies with Metabolic Disorders

The obesity epidemic is growing and poses significant risks to pregnancy. Metabolic impairment can be associated with short- and long-term maternal and perinatal morbidity and mortality. The cardiovascular implications are known in those with metabolic disorder outside of pregnancy; however, little is known of the cardiac function in pregnancies complicated by obesity. Maternal cardiac adaptation plays a vital role in normal pregnancy and is known to be involved in the pathophysiology of adverse pregnancy outcomes. Bariatric surgery is the most successful treatment for sustainable weight loss and pre-pregnancy bariatric surgery can drastically change the maternal metabolic profile and pregnancy outcomes. In this review, we discuss the available evidence on maternal cardiac function in pregnancies affected by obesity and its associated consequences of gestational diabetes and hypertension (chronic and hypertensive disorders in pregnancy), as well as pregnancies following bariatric surgery.

Maternal cardiovascular adaptation to pregnancy in obese pregnant women

INTRODUCTION

Obesity is known to be associated with cardiovascular compromise and a major risk factor for the development of hypertensive disorders in pregnancy. However, little is known about the effect of obesity on maternal cardiac function. The aim of this study was to investigate the effect of obesity on the maternal cardiovascular system.

MATERIAL AND METHODS

This was a prospective, observational, longitudinal study. Pregnant women with booking body mass index (BMI) ≥30 kg/m2 were compared with pregnant women with normal booking BMI 20-24.9 kg/m2. Participants were seen at three time points during pregnancy; 12-14, 20-24 and 30-32 weeks. At all visits, maternal blood pressure (BP) was measured, and cardiac geometry and function were assessed using two-dimensional trans-thoracic echocardiography. Multilevel linear mixed-effects models were used for all the comparisons.

RESULTS

Fifty-nine pregnant women with obesity were compared with 14 pregnant women with normal BMI. In women with obesity, the maternal BP, heart rate and cardiac output were higher and peripheral vascular resistance was lower (p < 0.01 for all comparisons) compared with normal BMI women. Women with obesity had altered cardiac geometry with higher left ventricular end diastolic diameter, intraventricular septal thickness, posterior wall diameter, relative wall thickness and left ventricular mass (p < 0.001 for all comparisons). There was also evidence of impaired diastolic indices in the obese group with a lower E/A ratio, tissue Doppler imaging E' lateral and medial and higher left atrial volume (p < 0.01 for all comparisons). Finally, women with obesity had reduced longitudinal function, as assessed by mitral plane annular systolic excursion, between the second and third trimester of pregnancy, indicating possible early cardiac dysfunction in this group.

CONCLUSIONS

Obesity is associated with maternal hyperdynamic circulation, altered cardiac geometry and suboptimal diastolic function, compared with normal BMI pregnant women, and these factors may contribute to the increased risk of complications in obese pregnant women.

Associations between Maternal Nutritional Status, Hemodynamic Parameters, and Delivery Outcomes in Low-Risk Pregnancies: A Prospective Observational Study

Maternal nutritional status represents a pivotal predictor of pregnancy outcome. This prospective observational study investigates the associations between maternal characteristics and nutritional habits at term, hemodynamic parameters, and pregnancy outcomes. Healthy women with singleton uncomplicated pregnancies were enrolled at 36-41 gestational weeks. At enrollment, a nutritional score (0-10) was calculated in order to quantify maternal adherence to a healthy diet and lifestyle. Maternal hemodynamic parameters were assessed by using the Ultrasonic Cardiac Output Monitor (USCOM), including cardiac output (CO), systemic vascular resistance (SVR) and Smith-Madigan inotropy index (SMII). Pregnancy outcomes were recorded at delivery. Associations between maternal characteristics and nutritional score, hemodynamic parameters, and pregnancy outcomes were investigated by using multi-adjusted generalized linear models. In total, 143 pregnancies were enrolled. Pregestational body mass index (BMI) was positively associated with SVR, and negatively associated with CO and SMII. Additionally, a positive association was detected between the nutritional score and SMII. Finally, CO was positively associated with birth and placental weight, while RVS showed a negative association with birth and placental weight. This study shows that maternal derangements in nutritional status and habits are associated with a compromised hemodynamic profile at term, with additional impacts on intrauterine growth.

Expert review: preeclampsia Type I and Type II

Pregnancy involves an interplay between maternal and fetal factors affecting changes to maternal anatomy and physiology to support the developing fetus and ensure the well-being of both the mother and offspring. A century of research has provided evidence of the imperative role of the placenta in the development of preeclampsia. Recently, a growing body of evidence has supported the adaptations of the maternal cardiovascular system during normal pregnancy and its maladaptation in preeclampsia. Debate surrounds the roles of the placenta vs the maternal cardiovascular system in the pathophysiology of preeclampsia. We proposed an integrated model of the maternal cardiac-placental-fetal array and the development of preeclampsia, which reconciles the disease phenotypes and their proposed origins, whether placenta-dominant or maternal cardiovascular system-dominant. These phenotypes are sufficiently diverse to define 2 distinct types: preeclampsia Type I and Type II. Type I preeclampsia may present earlier, characterized by placental dysfunction or malperfusion, shallow trophoblast invasion, inadequate spiral artery conversion, profound syncytiotrophoblast stress, elevated soluble fms-like tyrosine kinase-1 levels, reduced placental growth factor levels, high peripheral vascular resistance, and low cardiac output. Type I is more often accompanied by fetal growth restriction, and low placental growth factor levels have a measurable impact on maternal cardiac remodeling and function. Type II preeclampsia typically occurs in the later stages of pregnancy and entails an evolving maternal cardiovascular intolerance to the demands of pregnancy, with a moderately dysfunctional placenta and inadequate blood supply. The soluble fms-like tyrosine kinase-1-placental growth factor ratio may be normal or slightly disturbed, peripheral vascular resistance is low, and cardiac output is high, but these adaptations still fail to meet demand. Emergent placental dysfunction, coupled with an increasing inability to meet demand, more often appears with fetal macrosomia, multiple pregnancies, or prolonged pregnancy. Support for the notion of 2 types of preeclampsia observable on the molecular level is provided by single-cell transcriptomic survey of gene expression patterns across different cell classes. This revealed widespread dysregulation of gene expression across all cell types, and significant imbalance in fms-like tyrosine kinase-1 (FLT1) and placental growth factor, particularly marked in the syncytium of early preeclampsia cases. Classification of preeclampsia into Type I and Type II can inform future research to develop targeted screening, prevention, and treatment approaches.

Maternal hemodynamic profile during pregnancy and in the post-partum in hypertensive disorders of pregnancy and fetal growth restriction

BACKGROUND

Maternal cardiovascular changes, occurring since the beginning of pregnancy, are necessary for normal placentation and regular evolution of pregnancy.

OBJECTIVE

This study aimed to compare the hemodynamic profiles and cardiac remodeling of women with hypertensive disorders of pregnancy and either appropriate for gestational age fetuses or growth-restricted fetuses, women with normotensive pregnancies complicated by fetal growth restriction, and women with uncomplicated pregnancies, during pregnancy and the postpartum period.

STUDY DESIGN

A prospective longitudinal case-control design was used for this study. Over the study period, 220 eligible women with singleton pregnancies were selected for the analysis and divided into 4 groups: (1) hypertensive disorders of pregnancy with appropriate for gestational age fetuses; (2) hypertensive disorders of pregnancy with fetal growth restriction; (3) normotensive fetal growth restriction; and (4) controls. Ultrasound fetal biometry and fetoplacental Doppler velocimetry were performed at recruitment. Maternal hemodynamic assessment using transthoracic echocardiography was performed at the time of recruitment by a dedicated cardiologist blinded to maternal clinical data. The same assessments were performed in 104 patients at 32 weeks (interquartile range, 24-40) after delivery by the same cardiologist.

RESULTS

During pregnancy, women in the hypertensive-disorders-of-pregnancy-fetal-growth-restriction group showed significantly lower cardiac output and increased compared with those in the control group. These values were associated with concentric remodeling of the left ventricle owing to relatively increased wall thickness, which was not accompanied by an increase in left ventricular mass. Isolated fetal growth restriction presented similar but less important hemodynamic changes; however, there was no change in relative wall thickness. At postpartum follow-up, the hemodynamic parameters of women in the hypertensive-disorders-of-pregnancy-fetal-growth-restriction and isolated-fetal-growth-restriction groups reverted to values similar to those of the control group. Only 8.3% of women in these groups experienced hypertension even in the postpartum period, and asymptomatic stage-B cardiac failure was observed for 17% at echocardiography. In the group of women with hypertensive disorders of pregnancy and appropriate for gestational age fetuses, cardiac output increased as in normal pregnancies, but total vascular resistance was significantly higher; hypertension then occurred, along with ventricular concentric hypertrophy and diastolic dysfunction. At postpartum follow-up, women in the hypertensive-disorders-of-pregnancy-appropriate-for-gestational-age-fetus group showed significantly higher mean arterial pressure, total vascular resistance, and left ventricular mass compared with those in the control group. Persistent hypertension and asymptomatic stage-B cardiac failure were observed in 39.1% and 13% of women in the former group, respectively.

CONCLUSION

Pregnancies with hypertensive disorders of pregnancy and fetal growth restriction and normotensive pregnancies with fetal growth restriction were associated with the hemodynamic profile of lower heart rate and cardiac output, most likely because of abnormal adaptation to pregnancy, as confirmed by abnormal changes from pregnancy to the postpartum period. The heart rates and cardiac output of women in the hypertensive-disorders-of-pregnancy-appropriate-for-gestational-age-fetus group showed changes opposite to those observed in the hypertensive-disorders-of-pregnancy-fetal-growth-restriction and fetal-growth-restriction groups. Obesity and other metabolic risk factors, significantly prevalent in women in the hypertensive-disorders-of-pregnancy-appropriate-for-gestational-age-fetus group, predispose to hypertension and cardiovascular diseases during pregnancy and the postpartum period, potentially offering a window for personalized prevention. Such preventive strategies could differ in women with hypertensive disorders of pregnancy and fetal growth restriction characterized by poor early placental development.

Maternal body weight and estimated circulating blood volume: a non-linear approach

Postpartum haemorrhage continues to be a leading cause of morbidity and mortality in the obstetric population worldwide, especially in patients at extremes of body weight. Quantification of blood loss has been considered extensively in the literature. However, these volumes must be contextualised to appreciate the consequences of blood loss for individual parturients. Knowledge of a patient's peripartum circulating blood volume is essential to allow accurate interpretation of the significance of haemorrhage and appropriate resuscitation. Greater body weight in obesity can lead to overestimation of blood volume, resulting in inappropriately high thresholds for blood product transfusion and delays in treatment. The most recent Mothers and Babies: Reducing Risk through Audits and Confidential Enquiries across the UK (MBRRACE-UK) surveillance report demonstrated the risk to this population, with more than half of all maternal mortality recorded in parturients who were either overweight or obese. Current linear calculations used to estimate circulating blood volumes based on patients' weights could be contributing to this phenomenon, as blood volume increases at a disproportional rate to body composition. In this review, we summarise the relevant physiology and explore the existing literature on the estimation of circulating blood volume, both during pregnancy and in obesity. Building on key works and principal findings, we present a practical, nonlinear approach to the adjustment of estimated blood volume with increasing body mass. This clinical tool aims to reduce the clinical bias influencing the management of obstetric haemorrhage in a population already at increased risk of morbidity and mortality. Discussion of the limitations of this approach and the call for further research within this field completes this review.

Obesity in pregnancy is a predictor of persistent subclinical myocardial dysfunction over postpartum period

PURPOSE

No previous study provided a complete functional evaluation of all cardiac chambers in pregnant women with obesity. Moreover, the impact of cardiovascular changes associated with obesity in pregnancy on maternal outcome is unclear.

METHODS

46 consecutive pregnant women with obesity, defined by body mass index (BMI) ≥ 30 Kg/m2, and 83 age- (35.5 ± 4.1 vs. 34.1 ± 5.1 yrs, p = 0.11), ethnicity- (caucasian 65.2 vs. 66.3%, p = 0.90) and gestational week-matched (36.3 ± 1.7 vs. 36.5 ± 1.5 wks, p = 0.49) pregnant women without obesity (BMI < 30 Kg/m2) were examined in the first trimester (12-14 weeks), third trimester (36-38 weeks) and 6-10 weeks postpartum. All women underwent obstetric visit, blood tests and transthoracic echocardiography implemented with two-dimensional speckle tracking echocardiography analysis of biventricular and biatrial myocardial deformation indices at the three time points. Outcome was persistent subclinical myocardial dysfunction, defined as an absolute value of left ventricular global longitudinal strain (LV-GLS) less negative than - 20%, in postpartum.

RESULTS

Despite normal biventricular systolic function, all myocardial strain indices were significantly lower in pregnant women with obesity than controls. At 8.2 ± 2.2 weeks postpartum, LV-GLS remained less negative than - 20% in 86.9% of women with obesity in pregnancy. Maternal age (OR 1.68, 95%CI 1.14-2.48), third trimester BMI (OR 7.17, 95%CI 1.77-28.9) and third trimester neutrophil-to-lymphocyte ratio (NLR) (OR 1.75, 95%CI 1.22-2.51) were independently associated with outcome. Maternal age ≥ 35 years, BMI ≥ 30 Kg/m2 and NLR ≥ 5.5 were the optimal cut-off values for predicting persistent subclinical myocardial dysfunction in postpartum.

CONCLUSIONS

Pregnant women with obesity, age ≥ 35 yrs and low chronic inflammation have significantly increased risk of persistent subclinical myocardial dysfunction over postpartum.

Identification of Differential Expression Genes between Volume and Pressure Overloaded Hearts Based on Bioinformatics Analysis

Volume overload (VO) and pressure overload (PO) are two common pathophysiological conditions associated with cardiac disease. VO, in particular, often occurs in a number of diseases, and no clinically meaningful molecular marker has yet been established. We intend to find the main differential gene expression using bioinformatics analysis. GSE97363 and GSE52796 are the two gene expression array datasets related with VO and PO, respectively. The LIMMA algorithm was used to identify differentially expressed genes (DEGs) of VO and PO. The DEGs were divided into three groups and subjected to functional enrichment analysis, which comprised GO analysis, KEGG analysis, and the protein–protein interaction (PPI) network. To validate the sequencing data, cardiomyocytes from AR and TAC mouse models were used to extract RNA for qRT-PCR. The three genes with random absolute values of LogFC and indicators of heart failure (natriuretic peptide B, NPPB) were detected: carboxylesterase 1D (CES1D), whirlin (WHRN), and WNK lysine deficient protein kinase 2 (WNK2). The DEGs in VO and PO were determined to be 2761 and 1093, respectively, in this study. Following the intersection, 305 genes were obtained, 255 of which expressed the opposing regulation and 50 of which expressed the same regulation. According to the GO and pathway enrichment studies, DEGs with opposing regulation are mostly common in fatty acid degradation, propanoate metabolism, and other signaling pathways. Finally, we used Cytoscape’s three techniques to identify six hub genes by intersecting 255 with the opposite expression and constructing a PPI network. Peroxisome proliferator-activated receptor (PPARα), acyl-CoA dehydrogenase medium chain (ACADM), patatin-like phospholipase domain containing 2 (PNPLA2), isocitrate dehydrogenase 3 (IDH3), heat shock protein family D member 1 (HSPD1), and dihydrolipoamide S-acetyltransferase (DLAT) were identified as six potential genes. Furthermore, we predict that the hub genes PPARα, ACADM, and PNPLA2 regulate VO myocardial changes via fatty acid metabolism and acyl-Coa dehydrogenase activity, and that these genes could be employed as basic biomarkers for VO diagnosis and treatment.

Maternal cardiovascular adaptation to pregnancy in women with previous bariatric surgery

BACKGROUND

Obesity in pregnancy is associated with substantial risks, notably hypertensive disorders. Bariatric surgery achieves sustained weight loss and has several cardiovascular benefits, including positive effects on blood pressure, cardiac geometry, and both systolic and diastolic function. Pregnancy following bariatric surgery is also associated with improved outcomes, including a reduced risk of hypertensive disorders. The underlying mechanisms, however, remain uncertain. Maternal cardiovascular adaptation plays a vital role in maintaining a healthy pregnancy, and maladaptation has been associated with adverse pregnancy outcomes. However, to date, the maternal cardiovascular adaptation to pregnancy after bariatric surgery has not been investigated.

OBJECTIVE

To investigate the maternal cardiovascular adaptation to pregnancy in women with previous bariatric surgery compared with women with a similar early-pregnancy body mass index, age, and race but no history of weight loss surgery.

STUDY DESIGN

This was a prospective, observational, longitudinal study including pregnant women with (n=41) and without (n=41) a history of bariatric surgery. The participants were seen at 3 time points; at 12 to 14, 20 to 24, and 30 to 32 weeks of pregnancy. At each visit, the blood pressure was measured and the maternal cardiovascular system was assessed using transthoracic echocardiography. Two-dimensional speckle tracking was performed to assess the global longitudinal and circumferential strain on a subset of patients (15 in each group). Offline analysis was performed according to the European and American echocardiography guidelines. Multilevel linear mixed-effect models were used for all the comparisons.

RESULTS

Compared with the no-surgery group, women with previous bariatric surgery, had lower systolic and diastolic blood pressure, heart rate, and cardiac output across all the trimesters (P<.01 for all comparisons), with an evidence of more favorable diastolic indices, including a higher E-wave/A-wave ratio across the mitral valve (P<.001), higher mitral velocity at the lateral and medial annulus (E') (P=.01 and P=.03, respectively), and a lower left atrial volume (P<.05). Furthermore, women with previous bariatric surgery demonstrated lower global longitudinal (P<.01) and circumferential strain (P=.02), which is suggestive of better systolic function.

CONCLUSION

Our findings indicate better cardiovascular adaptation to pregnancy in women with previous bariatric surgery than in pregnant women of a similar early-pregnancy body mass index but no history of surgery.

Hemodynamic pathways of gestational hypertension and preeclampsia

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

Preeclampsia has two phenotypes which require different treatment strategies

The opinion on the mechanisms underlying the pathogenesis of preeclampsia still divides scientists and clinicians. This common complication of pregnancy has long been viewed as a disorder linked primarily to placental dysfunction, which is caused by abnormal trophoblast invasion, however, evidence from the previous two decades has triggered and supported a major shift in viewing preeclampsia as a condition that is caused by inherent maternal cardiovascular dysfunction, perhaps entirely independent of the placenta. In fact, abnormalities in the arterial and cardiac functions are evident from the early subclinical stages of preeclampsia and even before conception. Moving away from simply observing the peripheral blood pressure changes, studies on the central hemodynamics reveal two different mechanisms of cardiovascular dysfunction thought to be reflective of the early-onset and late-onset phenotypes of preeclampsia. More recent evidence identified that the underlying cardiovascular dysfunction in these phenotypes can be categorized according to the presence of coexisting fetal growth restriction instead of according to the gestational period at onset, the former being far more common at early gestational ages. The purpose of this review is to summarize the hemodynamic research observations for the two phenotypes of preeclampsia. We delineate the physiological hemodynamic changes that occur in normal pregnancy and those that are observed with the pathologic processes associated with preeclampsia. From this, we propose how the two phenotypes of preeclampsia could be managed to mitigate or redress the hemodynamic dysfunction, and we consider the implications for future research based on the current evidence. Maternal hemodynamic modifications throughout pregnancy can be recorded with simple-to-use, noninvasive devices in obstetrical settings, which require only basic training. This review includes a brief overview of the methodologies and techniques used to study hemodynamics and arterial function, specifically the noninvasive techniques that have been utilized in preeclampsia research.

The impact of short-term hyperglycemia and obesity on biventricular and biatrial myocardial function assessed by speckle tracking echocardiography in a population of women with gestational diabetes mellitus

BACKGROUND AND AIMS

To compare biventricular and biatrial myocardial strain indices assessed by two-dimensional speckle tracking echocardiography (2D-STE) in women with gestational diabetes mellitus (GDM) and those with uncomplicated pregnancy at the third trimester of pregnancy and in post-partum.

METHODS AND RESULTS

30 consecutive GDM women and 30 age-, ethnicity- and gestational week-matched controls without any comorbidity were examined in this prospective case-control study. All women underwent obstetric visit, blood tests and transthoracic echocardiography (TTE) implemented with 2D-STE analysis of all cardiac chambers at 36-38 weeks' gestation. TTE and 2D-STE were repeated at 6-10 weeks after delivery. At 36-38 weeks' gestation, GDM women, compared to controls, had significantly higher body mass index (BMI), blood pressure values and inflammatory markers. TTE showed increased left ventricular (LV) mass and impaired LV diastolic function in GDM women, whereas there was no significant difference between the groups in ejection fraction. 2D-STE revealed that biventricular global longitudinal strain (GLS) and biatrial reservoir strain indices were significantly lower in GDM women than controls. Third trimester BMI was inversely correlated with LV-GLS (r = -0.86) and was independently associated with reduced LV-GLS (less negative than -20%) in GDM women in post-partum (OR 1.81, 95%CI 1.14-2.89). A BMI value ≥ 30 kg/m² had 100% sensitivity and 99.5% specificity for identifying GDM women with impaired LV-GLS in post-partum (AUC = 0.97).

CONCLUSION

Women with GDM, compared to women with uncomplicated pregnancy, have significantly lower biventricular and biatrial myocardial deformation indices. These abnormalities may be persistent in post-partum in GDM women with obesity.

The Possibility of Using Bioelectrical Impedance Analysis in Pregnant and Postpartum Women

Pregnancy is a time of significant changes occurring in the composition of a woman’s body in order to provide support for the growth and development of the foetus. Bioelectrical impedance analysis (BIA) is used to assess the body composition and hydration status. This technique represents a non-invasive, reliable, and fast clinical approach, which is well tolerated by patients. A segmental impedance measurement might be advantageous in pregnant women, particularly in late pregnancy. The purpose of this paper is to provide a review of different applications of BIA in pregnant and postpartum women. It seems that BIA has a better prognostic potential for gestational and post-partum outcomes than body mass index. The BIA method can be successfully used to study the effect of excessive gestational weight gain in pregnancy on the development of obstetric complications. Studying the mother’s body composition and correlating it with her energy balance could facilitate the development of dietary recommendations for women. Evaluation of the body composition can provide important clues for diagnosis of gestational diabetes mellitus in pregnant women with a low risk of this disease. BIA is also used as one of the additional tests in assessing the risk of developing gestational hypertension and preeclampsia.

Preeclampsia Is a Syndrome with a Cascade of Pathophysiologic Events

This review integrates the currently available information on the molecular, cellular, and systemic mechanisms involved in the pathophysiology of preeclampsia. It highlights that the growth, protection, and promotion of the conceptus requires the modulation of an intact maternal immune system, communication between the mother and fetus, and adaptation of the maternal organic functions. A malfunction in any of these factors, on either side, will result in a failure of the cascade of events required for the normal course of pregnancy. Maladaptive processes, initially aiming to protect the conceptus, fail to anticipate the gradually increasing cardiovascular volume load during the course of pregnancy. As a result, multiple organ dysfunctions install progressively and eventually reach a state where mother and/or fetus are at risk of severe morbidity or even mortality, and where the termination of pregnancy becomes the least harmful solution. The helicopter view on pathophysiologic processes associated with preeclampsia, as presented in this paper, illustrates that the etiology of preeclampsia cannot be reduced to one single mechanism, but is to be considered a cascade of consecutive events, fundamentally not unique to pregnancy.