Protocol for the ECLIPSE-BRAZIL: a prospective cohort study on biomarkers and risk stratification for Preeclampsia

Preeclampsia (PE) is a leading cause of maternal and perinatal morbimortality, particularly in low- and middle-income countries. Despite advances in clinical management, its etiology and pathogenesis remain unclear, and effective predictive biomarkers are lacking. The Brazilian Longitudinal Study for the Investigation of Preeclampsia (ECLIPSE-BRAZIL) is a prospective cohort designed to investigate genetic, immunological, hemostatic, biochemical, and angiogenic profiles in pregnant women at risk for PE, aiming to identify biomarkers that effectively and affordably predict PE risk early in pregnancy.

ECLIPSE-BRAZIL follows 500 to 1,000 pregnant women receiving care at the High-Risk Prenatal Care clinics in Belo Horizonte and Divinópolis, Minas Gerais, Brazil. Clinical and laboratory assessments are conducted at four gestational stages and postpartum for PE cases. Clinical data, including sociodemographic, clinical and behavioral factors, and blood and urine samples are systematically collected. Plasma and urine levels of inflammatory markers, angiogenic factors, oxidative stress parameters, extracellular vesicles, microRNAs, endothelial and platelet markers will be analyzed. Participants are stratified by PE development and gestational age at diagnosis. Standardized criteria and data protocols ensure rigor, while quality check and audits enhance data reliability. To minimize follow-up loss, participants are contacted frequently, with flexible sampling and the use of hospital records.

ECLIPSE-BRAZIL will provide novel insights into PE pathophysiology, improving disease prediction and management. By studying a diverse population, we will identify biological signatures to inform health innovations: development of cost-effective diagnostic tools, point-of-care tests and simple clinical algorithms to identify women at risk before symptoms become severe. Finally, we will provide a deeper understanding of biological mechanisms driving PE and its subtypes, including endothelial function and immune response, which may lead to the discovery of new therapeutic targets. ECLIPSE-BRAZIL represents a major advancement in PE research, integrating a comprehensive evaluation of clinical, biochemical, and molecular markers throughout pregnancy. Its findings may inform public health policies and improve clinical practices worldwide.

Not applicable. This is an observational cohort study approved by the Research Ethics Committees, as documented under the following CAAE numbers: 12471918.0.0000.5149, 12471918.0.3002.5119, 12471918.0.3003.5130, 12471918.0.3006.5545.