Pregnant women at higher risk for preeclampsia (PE) are currently recommended to take low-dose aspirin (acetylsalicylic acid, ASA) daily from the first trimester until 36 weeks of gestation. High-risk women are identified through a multiparametric first-trimester screening that combines maternal history, blood pressure, uterine artery blood flow, and placental growth factor (PlGF). Although this screening effectively identifies women at risk, the majority of those classified as high risk will not develop PE. As a result, a large proportion of pregnant women receive prolonged aspirin treatment without benefit, while remaining exposed to its potential side effects, including increased bleeding risk.
Aspirin prevents PE primarily by improving placental development during the first half of pregnancy. Whether continuing ASA beyond 24-28 weeks provides additional protection remains unclear. A previous randomized trial demonstrated that stopping ASA at 24-28 weeks was non-inferior to continuing until 36 weeks in a predominantly European population. However, whether this finding applies to more diverse populations, including women of African origin who carry a substantially higher baseline risk of PE, has not been established.
This is a multicenter, randomized, open-label, parallel-group, phase III non-inferiority trial conducted across sites in Europe and Africa. A total of 15,160 pregnant women at high risk for PE from first-trimester screening, currently under ASA treatment, will be randomized in a 1:1 ratio before 28 weeks of gestation to either discontinue ASA at 24-28 weeks or continue ASA until 36 weeks of gestation.
Who can participate
Age range
18 Years
Sex
FEMALE
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Age 18 years or older at time of enrollment.
* Singleton pregnancy.
* Ability to read and understand the informed consent form.
* Having undergone first-trimester preeclampsia screening between 11+0 and 13+6 weeks of gestation using a validated multiparametric algorithm (FMF algorithm at a risk cutoff of 1:100, or Gaussian algorithm at a cutoff of 1:170) and being classified as high risk for preterm preeclampsia.
* Currently taking aspirin 150 mg/day initiated after first-trimester high-risk classification, in accordance with standard clinical practice.
* Voluntary signing of the informed consent form and willingness to comply with the study requirements, including acceptance of the assigned aspirin treatment duration, additional blood tests, and additional ultrasound assessments.
Exclusion Criteria:
* Early pregnancy loss, intrauterine fetal death, or fetus with major structural malformations diagnosed at the time of enrollment.
* Fetus affected by a known genetic or chromosomal disease.
* Contraindication, allergy, or intolerance to aspirin (acetylsalicylic acid).
* Any medical condition that makes aspirin discontinuation unsafe or impossible (e.g., antiphospholipid syndrome, mechanical heart valve, or other conditions requiring indefinite antiplatelet or anticoagulant therapy).
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Rate of preterm preeclampsia in both arms of the study (ASA vs no ASA).
Timeframe: From 20 weeks of gestation onwards
Trial details
NCT IDNCT07665853
SponsorHospital Universitari Vall d'Hebron Research Institute