Placental Findings in Postpartum Preeclampsia: A Comparative Retrospective Study

Predictive biomarkers and initial analysis of maternal immune alterations in postpartum preeclampsia reveal an immune-driven pathology

Introduction

Postpartum preeclampsia (PPPE) is an under-diagnosed condition, developing within 48 hours to 6 weeks following an uncomplicated pregnancy. The etiology of PPPE is still unknown, leaving patients vulnerable and making the identification and treatment of patients requiring postpartum care an unmet need. We aimed to understand the immune contribution to PPPE at the time of diagnosis, as well as uncover the predictive potential of perinatal biomarkers for the early postnatal identification of high-risk patients.

Methods

Placentas were collected at delivery from uncomplicated pregnancies (CTL) and PPPE patients for immunohistochemistry analysis. In this initial study, blood samples in PPPE patients were collected at the time of PPPE diagnosis (48h-25 days postpartum; mean 7.4 days) and compared to CTL blood samples taken 24h after delivery. Single-cell transcriptomics, flow cytometry, intracellular cytokine staining, and the circulating levels of inflammatory mediators were evaluated in the blood.

Results

Placental CD163+ cells and 1st trimester blood pressures can be valuable non-invasive and predictive biomarkers of PPPE with strong clinical application prospects. Furthermore, changes in immune cell populations, as well as cytokine production by CD14+, CD4+, and CD8+ cells, suggested a dampened response with an exhausted phenotype including decreased IL1β, IL12, and IFNγ as well as elevated IL10.

Discussion

Understanding maternal immune changes at the time of diagnosis and prenatally within the placenta in our sizable cohort will serve as groundwork for pre-clinical and clinical research, as well as guiding clinical practice for example in the development of immune-targeted therapies, and early postnatal identification of patients who would benefit from more thorough follow-ups and risk education in the weeks following an uncomplicated pregnancy.

Iron metabolism and ferroptosis: A pathway for understanding preeclampsia

Preeclampsia (PE) is a serious medical condition that poses a significant health risk to women and children worldwide, particularly in the middle- and low-income countries. It is a complex syndrome that occurs as a result of abnormal pregnancy. Hypertension is the most common symptom of PE, with proteinuria and specific organ systems as detrimental targets. PE's pathogenesis is diverse, and its symptoms can overlap with other diseases. In early pregnancy, when the placenta takes over control, oxidative stress may be closely associated with ferroptosis, a type of cell death caused by intracellular iron accumulation. Ferroptosis in the placenta is defined by redox-active iron availability, loss of antioxidant capacity and phospholipids containing polyunsaturated fatty acids (PUFA) oxidation. Recent studies suggest a compelling potential link between ferroptosis and PE. In this article, we comprehensively review the current understanding of PE and discuss one of its emerging underlying mechanisms, the ferroptosis pathway. We also provide perspective and analysis on the implications of this process in the diagnosis, prevention, and treatment of preeclampsia. We aim to bridge the gap between clinicians and basic scientists in understanding this harmful disease and challenge the research community to put more effort into this exciting new area.

A novel approach to joint prediction of preeclampsia and delivery timing using semicompeting risks

BACKGROUND

Preeclampsia is a pregnancy complication that contributes substantially to perinatal morbidity and mortality worldwide. Existing approaches to modeling and prediction of preeclampsia typically focus either on predicting preeclampsia risk alone, or on the timing of delivery following a diagnosis of preeclampsia. As such, they are misaligned with typical healthcare interactions during which the 2 events are generally considered simultaneously.

OBJECTIVE

This study aimed to describe the "semicompeting risks" framework as an innovative approach for jointly modeling the risk and timing of preeclampsia and the timing of delivery simultaneously. Through this approach, one can obtain, at any point during the pregnancy, clinically relevant summaries of an individual's predicted outcome trajectories in 4 risk categories: not developing preeclampsia and not having delivered, not developing preeclampsia but having delivered because of other causes, developing preeclampsia but not having delivered, and developing preeclampsia and having delivered.

STUDY DESIGN

To illustrate the semicompeting risks methodology, we presented an example analysis of a pregnancy cohort from the electronic health record of an urban, academic medical center in Boston, Massachusetts (n=9161 pregnancies). We fit an illness-death model with proportional-hazards regression specifications describing 3 hazards for timings of preeclampsia, delivery in the absence of preeclampsia, and delivery following preeclampsia diagnosis.

RESULTS

The results indicated nuanced relationships between a variety of risk factors and the timings of preeclampsia diagnosis and delivery, including maternal age, race/ethnicity, parity, body mass index, diabetes mellitus, chronic hypertension, cigarette use, and proteinuria at 20 weeks' gestation. Sample predictions for a diverse set of individuals highlighted differences in projected outcome trajectories with regard to preeclampsia risk and timing, and timing of delivery either before or after preeclampsia diagnosis.

CONCLUSION

The semicompeting risks framework enables characterization of the joint risk and timing of preeclampsia and delivery, providing enhanced, meaningful information regarding clinical decision-making throughout the pregnancy.

Peripartum and Long-Term Maternal Cardiovascular Health After Preeclampsia

There is widespread acceptance of the increased prevalence of cardiovascular diseases occurring within 1 to 2 decades in women following a preeclamptic pregnancy. More recent evidence suggests that the deranged biochemical and echocardiographic findings in women do not resolve in the majority of preeclamptic women following giving birth. Many women continue to be hypertensive in the immediate postnatal period with some exhibiting occult signs of cardiac dysfunction. There is now promising evidence that with close monitoring and effective control of blood pressure control in the immediate postnatal period, women may have persistently lower blood pressures many years after stopping their medication. This review highlights the evidence that delivering effective medical care in the fourth trimester of pregnancy can improve the long-term cardiovascular health after a preeclamptic birth.

Setting a stage: Inflammation during preeclampsia and postpartum

Preeclampsia (PE) is a leading cause of maternal and fetal mortality worldwide. The immune system plays a critical role in normal pregnancy progression; however, inappropriate inflammatory responses have been consistently linked with PE pathophysiology. This inflammatory phenotype consists of activation of the innate immune system, adaptive immune system, and increased inflammatory mediators in circulation. Moreover, recent studies have shown that the inflammatory profile seen in PE persists into the postpartum period. This manuscript aims to highlight recent advances in research relating to inflammation in PE as well as the inflammation that persists postpartum in women after a PE pregnancy. With the advent of the COVID-19 pandemic, there has been an increase in obstetric disorders associated with COVID-19 infection during pregnancy. This manuscript also aims to shed light on the relationship between COVID-19 infection during pregnancy and the increased incidence of PE in these women.

Postpartum preeclampsia or eclampsia: defining its place and management among the hypertensive disorders of pregnancy

High blood pressure in the postpartum period is most commonly seen in women with antenatal hypertensive disorders, but it can develop de novo in the postpartum time frame. Whether postpartum preeclampsia or eclampsia represents a separate entity from preeclampsia or eclampsia with antepartum onset is unclear. Although definitions vary, the diagnosis of postpartum preeclampsia should be considered in women with new-onset hypertension 48 hours to 6 weeks after delivery. New-onset postpartum preeclampsia is an understudied disease entity with few evidence-based guidelines to guide diagnosis and management. We propose that new-onset hypertension with the presence of any severe features (including severely elevated blood pressure in women with no history of hypertension) be referred to as postpartum preeclampsia after exclusion of other etiologies to facilitate recognition and timely management. Older maternal age, black race, maternal obesity, and cesarean delivery are all associated with a higher risk of postpartum preeclampsia. Most women with delayed-onset postpartum preeclampsia present within the first 7 to 10 days after delivery, most frequently with neurologic symptoms, typically headache. The cornerstones of treatment include the use of antihypertensive agents, magnesium, and diuresis. Postpartum preeclampsia may be associated with a higher risk of maternal morbidity than preeclampsia with antepartum onset, yet it remains an understudied disease process. Future research should focus on the pathophysiology and specific risk factors. A better understanding is imperative for patient care and counseling and anticipatory guidance before hospital discharge and is important for the reduction of maternal morbidity and mortality in the postpartum period.

Preeclampsia: Linking Placental Ischemia with Maternal Endothelial and Vascular Dysfunction

Preeclampsia (PE), a hypertensive disorder, occurs in 3% to 8% of pregnancies in the United States and affects over 200,000 women and newborns per year. The United States has seen a 25% increase in the incidence of PE, largely owing to increases in risk factors, including obesity and cardiovascular disease. Although the etiology of PE is not clear, it is believed that impaired spiral artery remodeling of the placenta reduces perfusion, leading to placental ischemia. Subsequently, the ischemic placenta releases antiangiogenic and pro-inflammatory factors, such as cytokines, reactive oxygen species, and the angiotensin II type 1 receptor autoantibody (AT1-AA), among others, into the maternal circulation. These factors cause widespread endothelial activation, upregulation of the endothelin system, and vasoconstriction. In turn, these changes affect the function of multiple organ systems including the kidneys, brain, liver, and heart. Despite extensive research into the pathophysiology of PE, the only treatment option remains early delivery of the baby and importantly, the placenta. While premature delivery is effective in ameliorating immediate risk to the mother, mounting evidence suggests that PE increases risk of cardiovascular disease later in life for both mother and baby. Notably, these women are at increased risk of hypertension, heart disease, and stroke, while offspring are at risk of obesity, hypertension, and neurological disease, among other complications, later in life. This article aims to discuss the current understanding of the diagnosis and pathophysiology of PE, as well as associated organ damage, maternal and fetal outcomes, and potential therapeutic avenues. © 2021 American Physiological Society. Compr Physiol 11:1315-1349, 2021.

Fetal gender, serum human chorionic gonadotropin, and testosterone in women with preeclampsia

OBJECTIVES

Evaluation of the association between fetal gender, serum beta-human chorionic gonadotropin, and serum testosterone, and preeclampsia.

METHODS

Case-control study conducted at the Obstetrics and Gynecology Department. 120 patients divided into study group (patients with preeclampsia subdivided into mild and severe) and control group (normotensive women).

INTERVENTIONS

Fetal gender was determined. Serum testosterone and HCG levels were estimated at 32 weeks or at the time of diagnosis of preeclampsia (study group) or recruitment (control group).

RESULTS

Positive association between the male gender of the fetus and preeclampsia. Increased HCG and Testosterone were associated with developing preeclampsia.

CONCLUSION

The mechanism of preeclampsia could be androgen-mediated. There is a significant correlation between serum HCG and testosterone and preeclampsia.