ASPRE trial: effects of aspirin on mean arterial blood pressure and uterine artery pulsatility index trajectories in pregnancy

Preeclampsia pathogenesis and prediction - where are we now: the focus on the role of galectins and miRNAs

Preeclampsia is a complex, progressive multisystem hypertensive disorder during pregnancy that significantly contributes to increased maternal and perinatal morbidity and mortality. Two screening algorithms are in clinical use for detecting preeclampsia: first-trimester screening, which has been developed and validated for predicting early-onset preeclampsia but is less effective for late-onset disease; and the sFlt-1:PlGF biomarker ratio (soluble tyrosine kinase and placental growth factor) used in suspected cases of preeclampsia. This ratio has a high negative predictive value, allowing for the reliable exclusion of the disease. Both of these screening tests have not met expectations. This review attempts to summarize the current knowledge on the pathogenesis and prediction of preeclampsia and to draw attention to novel biomarkers with a focus on microRNAs and galectins. Although these molecules belong to two distinct biological classes, they functionally converge in regulating placental and immune pathways. Ample evidence supports their involvement in the molecular mechanisms underlying preeclampsia. Based on current knowledge, galectin-13, C19MC members, and miRNA-210 are associated with the trophoblast/placenta and conditions of placental ischemia or hypoxia. Their levels differ significantly in pregnant women at risk of preeclampsia as early as the late first and early second trimester, making them potential markers for predicting preeclampsia.

Effect of aspirin on biomarker profile in women at high risk for preeclampsia

BACKGROUND

There is limited evidence in the literature regarding the temporal changes of preeclampsia-related biomarkers during pregnancy in high-risk women who develop preeclampsia despite the administration of aspirin prophylaxis.

OBJECTIVE

This study aimed to compare the temporal changes in mean arterial pressure, uterine artery pulsatility index, placental growth factor, and soluble fms-like tyrosine kinase-1 across gestation in women identified as having high risk for preterm preeclampsia receiving aspirin prophylaxis and low-risk women without aspirin treatment.

STUDY DESIGN

This was a prospective longitudinal nested case-control study of 2007 women with singleton pregnancies who participated in the first-trimester screen-and-prevent program for preeclampsia at the Prince of Wales Hospital, Hong Kong Special Administrative Region, China, between January 2020 and May 2023. The risk of developing preterm preeclampsia was determined using the Fetal Medicine Foundation triple test (maternal factors, mean arterial pressure, uterine artery pulsatility index, and placental growth factor). High-risk women (adjusted risk ≥1:100) were administered a daily dose of aspirin at either 100 or 160 mg according to maternal weight, starting before 16 weeks until 36 weeks or until delivery or the onset of preeclampsia before 36 weeks. Low-risk women were matched according to maternal age, weight, and the date of the scan. The participants were followed up at 12 to 15+6, 20 to 24+6, and 30 to 37+6 weeks to measure mean arterial pressure, uterine artery pulsatility index, placental growth factor, and soluble fms-like tyrosine kinase-1 at each visit. The level of biomarker was expressed as multiple of the median. Log10 transformation was applied to fit the data to a Gaussian distribution before statistical analysis. A linear mixed-effects analysis was performed to compare the longitudinal changes of these biomarkers across gestation between the study groups.

RESULTS

Our study involved 403 low-risk women without preeclampsia, 1471 high-risk women without preeclampsia, and 133 high-risk women who developed preeclampsia. The low-risk group had significantly lower estimated marginal mean log10 mean arterial pressure multiple of the median, log10 uterine artery pulsatility index multiple of the median, and log10 soluble fms-like tyrosine kinase-1 multiple of the median, and higher estimated marginal mean log10 placental growth factor multiple of the median across gestation compared with the high-risk groups (P<.001). Among high-risk women, those who developed preeclampsia exhibited a significantly higher estimated marginal mean log10 mean arterial pressure multiple of the median (0.06378 vs 0.02985; P<.001), log10 uterine artery pulsatility index multiple of the median (0.08651 vs 0.02226; P<.001), and log10 soluble fms-like tyrosine kinase-1 multiple of the median (0.13204 vs 0.01234; P<.001), and lower estimated marginal mean log10 placental growth factor multiple of the median (-0.33504 vs -0.16388; P<.001) across gestation compared with those without preeclampsia. In the individual gestational time point analysis, compared with high-risk women without preeclampsia, those who developed preeclampsia exhibited higher log10 mean arterial pressure multiple of the median in all 3 trimesters, higher log10 uterine artery pulsatility index multiple of the median and lower log10 placental growth factor multiple of the median in the second and third trimesters, and higher log10 soluble fms-like tyrosine kinase-1 multiple of the median in the third trimester.

CONCLUSION

This study demonstrated that high-risk women who developed preeclampsia consistently exhibited high mean arterial pressure levels from the first trimester that remained unchanged during pregnancy, high uterine artery pulsatility index levels and low placental growth factor levels starting from the second trimester, and high soluble fms-like tyrosine kinase-1 levels in the third trimester compared with those who did not develop preeclampsia despite the administration of low-dose aspirin. These findings underscore the role of these biomarkers in further risk stratification for the development of preeclampsia among high-risk women following aspirin administration.

Aspirin Improves Uterine Artery Function in Hypercholesterolemic Preeclampsia

BACKGROUND

Excessive hypercholesterolemia in pregnancy increases the risk of preeclampsia (HC-PE), though the mechanisms remain unclear. We recently showed that uterine artery function is impaired in HC-PE pregnancies via activation of the TLR4 (toll-like receptor 4)/PGHS1 (prostaglandin H synthase 1) pathway. Low-dose aspirin lowers preeclampsia risk in high-risk pregnancies by inhibiting PGHS1, but its effects in HC-PE pregnancies are not known. Moreover, oxidized low-density lipoprotein (oxLDL) levels rise in HC-PE, potentially activating TLR4 and LOX-1 (lectin-like oxLDL receptor-1; scavenger receptor linked to vascular dysfunction in preeclampsia). However, whether this occurs in HC-PE is not known.

METHODS

Sprague Dawley rats received a control or high-cholesterol diet (to induce HC-PE) from gestational day 6 to 20, with placebo or low-dose aspirin (1.5 mg/kg daily) given from gestational day 10 to 20. On gestational day 20, pregnancy outcomes and uterine artery function were assessed.

RESULTS

Uterine artery blood flow velocity and placental weights were higher in HC-PE placebo-treated dams versus controls, but these were reduced by low-dose aspirin. Endothelium-dependent vasodilation was impaired in the uterine arteries of the HC-PE placebo group versus controls and was corrected by low-dose aspirin. Ex vivo inhibition of TLR4, PGHS1, or LOX-1 also normalized endothelium-dependent vasodilation in the HC-PE placebo-treated dams. Exposure to oxLDL in the bath (modeling a secondary hit) further impaired endothelium-dependent vasodilation in the uterine arteries of the HC-PE placebo group, partially via TLR4 and LOX-1, which was prevented by low-dose aspirin.

CONCLUSIONS

Low-dose aspirin improved uterine artery endothelial function in HC-PE pregnancies; likely by suppressing the TLR4/LOX-1/PGHS1 pathway.

The Impact of Overweight and Obesity on Pregnancy: A Narrative Review of Physiological Consequences, Risks and Challenges in Prenatal Care, and Early Intervention Strategies

BACKGROUND

While substantial literature exists on the intersection of overweight/obesity (OWO) and pregnancy, much of it focuses on specific aspects, making it difficult to maintain an overview of clinically relevant factors for optimal care of OWO women throughout pregnancy.

OBJECTIVES

To provide a comprehensive synthesis of the existing literature, covering the full spectrum of clinically relevant information needed to manage OWO women from preconception to birth.

METHODS

For this narrative review a literature search was conducted on PubMed in January 2025. Eligible studies included full-text English articles with data from human subjects, with no restrictions on publication date.

FINDINGS

The impact of OWO on pregnancy is multifaceted, encompassing four interrelated themes: physiological consequences, emerging risks, challenges in prenatal care, and intervention strategies. OWO women exhibit differences in metabolic and inflammatory pathways compared to normal-weight women, reflected in altered laboratory tests. When managing gestational diabetes and preeclampsia, obesity-related characteristics must be considered. Clinicians need to be alert of obesity-mediated fetal complications, including overgrowth, malformations, stillbirth, and preterm birth, while navigating challenges in ultrasound measurements. Interventions during the preconception and prenatal periods provide key opportunities to optimize maternal weight and reduce the risk of long-term disease development.

CONCLUSION

The review's insights enhance clinical practice and call on researchers and policymakers to prioritize strategies that offer early counseling for obese pregnant women. These initiatives aim to optimize outcomes for both mother and child and contribute to combating the global obesity crisis.

Statins for preventing preeclampsia

OBJECTIVES

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To evaluate the relative benefits and harms of statins for preeclampsia prevention in pregnant women.

Prediction of late-onset preeclampsia using plasma proteomics: a longitudinal multi-cohort study

Preeclampsia is a pregnancy disorder with substantial perinatal and maternal morbidity and mortality. Pregnant women at risk of preeclampsia would benefit from early detection for follow-up, timely interventions and delivery. Several attempts have been made to identify protein biomarkers of preeclampsia, but findings vary with demographics, clinical characteristics, and time of sampling. In the current study, we combined three independent longitudinal pregnancy cohorts (Detroit, Stanford and Oslo) resulting in 124 late-onset preeclampsia (LOPE) cases and 178 gestational age matched controls, and analyzed > 1000 proteins in maternal plasma sampled between 12 and 34 weeks of gestation. Differential abundance analysis of combined protein data revealed increased deviation in protein abundance trajectories throughout gestation in women destined to develop LOPE compared to controls. There were no differentially abundant proteins at time interval T1 (12-19 weeks), yet 31 differentially abundant proteins were found at time interval T2 (19-27 weeks), and 48 proteins at time interval T3 (27- 34 weeks). Multi-protein random forest models assessed via cross-validation predicted LOPE with an area under the ROC curve of 0.72 (0.65-0.78), 0.76 (0.71-0.81) and 0.80 (0.75-0.85) at time interval T1, T2 and T3, respectively. The results at T3 were confirmed using a leave-one-cohort-out analysis suggesting cross-cohort consistency, and at T1 and T2 when the largest two cohorts were used as training sets.

Aspirin for evidence-based preeclampsia prevention trial: effects of aspirin on maternal serum pregnancy-associated plasma protein A and placental growth factor trajectories in pregnancy

BACKGROUND

The exact mechanism by which aspirin prevents preeclampsia remains unclear. Its effects on serum placental biomarkers throughout pregnancy are also unknown.

OBJECTIVE

To investigate the effects of aspirin on serum pregnancy-associated plasma protein A and placental growth factor trajectories using repeated measures from women at increased risk of preterm preeclampsia.

STUDY DESIGN

This was a longitudinal secondary analysis of the Combined Multimarker Screening and Randomized Patient Treatment with Aspirin for Evidence-based Preeclampsia Prevention trial using repeated measures of pregnancy-associated plasma protein A and placental growth factor. In the trial, 1620 women at increased risk of preterm preeclampsia were identified using the Fetal Medicine Foundation algorithm at 11 to 13+6 weeks of gestation, of whom 798 were randomly assigned to receive aspirin 150 mg and 822 to receive placebo daily from before 14 weeks to 36 weeks of gestation. Serum biomarkers were measured at baseline and follow-up visits at 19 to 24, 32 to 34, and 36 weeks of gestation. Generalized additive mixed models with treatment by gestational age interaction terms were used to investigate the effect of aspirin on biomarker trajectories over time.

RESULTS

Overall, there were 5507 pregnancy-associated plasma protein A and 5523 placental growth factor measurements. Raw pregnancy-associated plasma protein A values increased over time, and raw placental growth factor increased until 32 weeks of gestation followed by a decline. The multiple of the median mean values of the same biomarkers were consistently below 1.0 multiple of the median, reflecting the high-risk profile of the study population. Trajectories of mean pregnancy-associated plasma protein A and placental growth factor multiple of the median values did not differ significantly between the aspirin and placebo groups (aspirin treatment by gestational age interaction P values: .259 and .335, respectively).

CONCLUSION

In women at increased risk of preterm preeclampsia, aspirin 150 mg daily had no significant effects on pregnancy-associated plasma protein A or placental growth factor trajectories when compared to placebo.

Placenta-Mediated Conditions: Past, Present, and Future Perspectives

Pregnancy is a highly regulated biological condition in which a successful outcome is heavily dependent on maintaining a delicate balance through maternal-fetal dialog at various levels [...].

First-trimester preterm preeclampsia prediction model for prevention with low-dose aspirin

INTRODUCTION

Preeclampsia (PE) is a major maternal and fetal threat. Previous risk-scoring methods in guidelines lacked precision. The Fetal Medicine Foundation (FMF) proposed a first-trimester PE screening model using Bayes' theorem.

PE PREDICTION MODEL

FMF prediction model combines maternal characteristics and medical/obstetrical history to determine prior risk and further incorporate maternal blood pressure, maternal serum biomarkers, and uterine Doppler pulsatility index expressed as multiples of the median (MoM) to estimate posterior risk.

LOW-DOSE ASPIRIN PREVENTION

Low-dose aspirin is one of the potential PE prevention strategies. Initiating it before 16 weeks is crucial. Aspirin's antiplatelet and anti-inflammatory properties align with PE's pathophysiology. Dosing and resistance warrant further study, but a standard regimen of 150 mg nightly, starting before 16 weeks, is widely supported.

PE PREVENTION IN PRACTICE

Clinical trials, including ASPRE, affirm aspirin's role in PE prevention. Starting aspirin based on FMF screening significantly reduces preterm PE and associated complications.

ADVANCEMENTS AND PROSPECTS

Emerging research explores predictors like maternal ophthalmic arterial waveform. Regional variations, especially in Asian populations, are considered. Machine learning and AI show promise, but examiner expertise remains essential for accurate prediction. In conclusion, integrating FMF's first-trimester PE screening with low-dose aspirin offers a promising strategy. Further advancements may enhance precision and broaden prevention efforts.

Cell-free DNA methylation-based preeclampsia prediction: A journey to improve maternal health

Presymptomatic prediction of preeclampsia (PE) is crucial to enable early prophylactic treatment. Current screening tools are either complex or lack predictive value. We recently demonstrated that cell-free DNA methylation can be leveraged to predict early-onset PE in 57% at a 10% false positive rate. Importantly, this minimally invasive screening test can be implemented as an add-on to current widespread noninvasive prenatal aneuploidy screening. Here, we highlight the pitfalls and promising prospects of this research.

Reducing the Risk of Pre-Eclampsia in Women with Polycystic Ovary Syndrome Using a Combination of Pregnancy Screening, Lifestyle, and Medical Management Strategies

Polycystic ovary syndrome (PCOS) is a multisystem disorder that presents with a variety of phenotypes involving metabolic, endocrine, reproductive, and psychological symptoms and signs. Women with PCOS are at increased risk of pregnancy complications including implantation failure, miscarriage, gestational diabetes, fetal growth restriction, preterm labor, and pre-eclampsia (PE). This may be attributed to the presence of specific susceptibility features associated with PCOS before and during pregnancy, such as chronic systemic inflammation, insulin resistance (IR), and hyperandrogenism, all of which have been associated with an increased risk of pregnancy complications. Many of the features of PCOS are reversible following lifestyle interventions such as diet and exercise, and pregnant women following a healthy lifestyle have been found to have a lower risk of complications, including PE. This narrative synthesis summarizes the evidence investigating the risk of PE and the role of nutritional factors in women with PCOS. The findings suggest that the beneficial aspects of lifestyle management of PCOS, as recommended in the evidence-based international guidelines, extend to improved pregnancy outcomes. Identifying high-risk women with PCOS will allow targeted interventions, early-pregnancy screening, and increased surveillance for PE. Women with PCOS should be included in risk assessment algorithms for PE.

Prevention of preeclampsia

Preeclampsia is a relatively common pregnancy complication and constitutes a major cause of morbidity and mortality for mothers and children worldwide. It disproportionally affects low-resource countries. Appropriate identification of individuals at increased risk and prevention of the disease and its complications remain healthcare and research priorities, and the investigation of potential interventions to prevent preeclampsia has driven much of the obstetric research in recent decades. In this article, we review the scientific literature on the topic, highlighting established benefits and remaining questions regarding different non-pharmacological and pharmacological strategies, including exercise, the timing of birth, aspirin and calcium use, among others, as well as potential novel therapies under investigation.

Aspirin at 75 to 81 mg Daily for the Prevention of Preterm Pre-Eclampsia: Systematic Review and Meta-Analysis

Background: Aspirin at 150 mg daily, initiated in the 1st trimester of pregnancy, prevents preterm pre-eclampsia. We aimed to estimate whether a dose of 75 to 81 mg daily can help to prevent preterm pre-eclampsia as well. Methods: A systematic search was conducted using multiple databases and meta-analyses of randomized controlled trials (RCTs) that compared aspirin initiated in the first trimester of pregnancy to placebo or no treatment, following the PRISMA guidelines and the Cochrane risk of bias tool. Results: We retrieved 11 RCTs involving 13,981 participants. Five RCTs had a low risk of bias, one at unclear risk, and fiver had a high risk of bias. A pooled analysis demonstrated that doses of 75 to 81 mg of aspirin, compared to a placebo or no treatment, was not associated with a significant reduction in preterm pre-eclampsia (8 studies; 12,391 participants; relative risk, 0.66; 95% confidence interval: 0.27 to 1.62; p = 0.36), but there was a significant heterogeneity across the studies (I2 = 61%, p = 0.02). Conclusion: It cannot be concluded that taking 75 to 81 mg of aspirin daily reduces the risk of preterm pre-eclampsia. However, given the significant heterogeneity between the studies, the true effect that such a dose of aspirin would have on pregnancy outcomes could not be properly estimated.