Deadline 21 December 2026
Background
Hypertensive disorders of pregnancy, particularly pre-eclampsia and eclampsia, remain important causes of maternal and newborn mortality, severe morbidity and long-term disability worldwide.1,2 In recognition of the growing need for coordinated global action to improve the prevention and management of hypertensive disorders of pregnancy, WHO and its partners have developed the Global roadmap for hypertensive disorders of pregnancy from 2026 to 2035 and beyond.3 The Roadmap identifies coordinated actions across five strategic areas: research and innovation; norms and standards; access to health products; implementation; and advocacy and accountability. As part of WHO’s efforts to develop up-to-date and globally applicable norms and standards, WHO has initiated a rigorous reappraisal of the definition of pre-eclampsia and the approaches used to identify women at increased risk, as fundamental steps towards improving care and outcomes worldwide.
Large contemporary cohorts and trials provide an opportunity to evaluate candidate diagnostic and prognostic markers across diverse settings and populations. Harmonization of individual participant data will enable the consistent application of outcome definitions, evaluation of multiple thresholds without reliance on published categories, and assessment of combinations and trajectories of markers.
Purpose
To develop a robust evidence base for the definition of pre-eclampsia and the identification of women at increased risk, the World Health Organization (WHO) is gathering data from published and unpublished studies and from routine or administrative data systems across different contexts and geographical regions.
How to contribute
Data proposed for inclusion in this project must meet the study-level eligibility criteria for the pooled database. As a first step, the principal investigator or authorized data custodian should complete the online eligibility screening form. The information provided will enable WHO to assess whether the dataset meets the study-level eligibility criteria.
WHO will review each submission and inform the principal investigator or data custodian of the outcome of the eligibility assessment. For eligible datasets, WHO will ask the contributing institution to provide any existing data-sharing agreement it may have with WHO. Where no such agreement exists, WHO will provide a standard agreement as the basis for discussion and agreement between the parties. Data may be transferred only after the agreement has been signed by both parties.
The acquired de-identified data will be stored in a secure WHO repository established specifically for this project. WHO will have sole responsibility for managing and updating the repository. Collaborating principal investigators will retain access to their own contributed raw data but will not have access to raw data contributed by other institutions. The shared data will be used only for the agreed objectives of this project.
Documentation
Before submitting the eligibility screening form, prospective contributors are encouraged to review the following documents:
- Concept note of the global call for data;
- Data Sharing Standards (DSS), including a data sharing process
Principal investigators and data custodians should familiarize themselves with these documents in case their data are found to be eligible. Where the contributing institution does not already have an appropriate data-sharing agreement with WHO, WHO will provide a standard agreement containing the relevant data-sharing principles as the starting point for discussion.
Acknowledgements for sharing data
By actively participating in data sharing, Principal Investigators will contribute to the collective knowledge base and understanding of pre-eclampsia. Principal Investigators providing data that is used in a specific analysis will be invited to join the WHO Consortium on Pre-eclampsia Definition, participate in the writing group of any publication, and potentially be included as a named author on any data synthesis manuscripts.
Queries and clarifications
If you have any questions, please contact us at PEDefinitionProject@who.int with the following email subject "Questions – Global call for data on pre-eclampsia".
References
- World Health Organization. Trends in maternal mortality 2000 to 2020: estimates by WHO, UNICEF, UNFPA, World Bank Group and UNDESA/Population Division. Geneva: World Health Organization; 2023.
- Cresswell JA, Alexander M, Chong MYC, Link HM, Pejchinovska M, Gazeley U, et al. Global and regional causes of maternal deaths 2009–20: a WHO systematic analysis. Lancet Glob Health. 2025;13(4):e626–e634.
- World Health Organization. Global roadmap for hypertensive disorders of pregnancy from 2026 to 2035 and beyond. Geneva: World Health Organization; 2026.