AuthorisedPhase III and phase IV (Integrated)Interventional

Optimizing Aspirin Use for Preeclampsia Prevention

This study is investigating the best time for pregnant women, who are already taking low-dose aspirin to prevent pre-eclampsia, to stop their medication. Half the women in the study will stop taking aspirin between 24 and 26 weeks of pregnancy, while the other half will continue taking it until 36 weeks. The main goal is to find out if stopping aspirin earlier is just as good at preventing early pre-eclampsia, without putting the mum or baby at any extra risk. We'll also be checking if stopping aspirin earlier can help reduce heavy bleeding for the mother. This research aims to make sure pregnant women get the right treatment at the right time.

At a glance

Status

Authorised

Phase

Phase III and phase IV (Integrated)

Sponsor

Fundacio Hospital Universitari Vall D’Hebron Institut De Recerca

Enrolment target

11,836

Start

07 May 2026

Obstetrics – Preeclampsia

What is this study about?

This study is about a medication called aspirin, which is sometimes given to pregnant women to help prevent a condition called pre-eclampsia. Pre-eclampsia is a serious problem that can happen during pregnancy, causing high blood pressure and other issues for the mother and baby. We already know that taking a low dose of aspirin can help prevent pre-eclampsia in some women.

What we don't know for sure is the best time for women to stop taking this aspirin during their pregnancy. Currently, many women take it until quite late in their pregnancy, around 36 weeks. This study wants to see if stopping aspirin a bit earlier, between 24 and 26 weeks, is just as effective at preventing the more serious, early form of pre-eclampsia.

By carefully comparing these two approaches, we hope to find out if stopping aspirin earlier is safe and effective, and if it might even reduce the risk of heavy bleeding for mothers. This research is really important because it could help doctors give pregnant women the best and safest advice on how long to take aspirin.

Key takeaways

The study is about when to stop aspirin for pre-eclampsia prevention in pregnancy.
It compares stopping aspirin at 24-26 weeks versus 36 weeks.
The main aim is to see if stopping earlier is just as safe and effective.
It also checks if stopping aspirin earlier reduces heavy bleeding for the mother.
Participation involves continuing your usual care with specific aspirin instructions.

Who may be eligible?

This study is looking for women who are currently pregnant and are already taking low-dose aspirin to prevent pre-eclampsia. You would need to be at least 18 years old to take part.

Your doctor would check other specific health details to make sure this study is right and safe for you. This often includes looking at your general health and how many weeks pregnant you are.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Are you currently pregnant?
Are you already taking low-dose aspirin to prevent pre-eclampsia?
Are you willing to potentially stop aspirin at different times in your pregnancy?
Are you comfortable with extra monitoring during your pregnancy?

Answer every question to see your result.

What does participation involve?

If you decide to join this study, you would continue your regular antenatal care. The key difference would be when you stop taking your low-dose aspirin. You would either be asked to stop taking it between 24 and 26 weeks of your pregnancy, or continue taking it until 36 weeks, depending on which group you are assigned to.

Your healthcare team would closely monitor you and your baby throughout your pregnancy, much like routine care, but they would also collect some specific information related to the study. This might include regular checks of your blood pressure and other tests. The total duration of your active involvement would be until after your baby is born, allowing doctors to look at results for both you and your newborn.

Potential risks and benefits

Taking part in this study may offer the benefit of helping doctors understand the best and safest way to use aspirin during pregnancy, which could improve care for many women in the future. For you personally, there's a chance that stopping aspirin earlier might reduce your risk of heavy bleeding, or continue to provide the established benefits of aspirin for pre-eclampsia prevention. However, as with any study, there could be risks. If you stop aspirin earlier, there's a small chance it might not be as effective for you personally at preventing pre-eclampsia, although we are hoping to show it is just as good. Your health and your baby's health will be closely monitored throughout the study. You are free to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Spain

Common questions

What is pre-eclampsia?

Pre-eclampsia is a serious condition that can develop during pregnancy, usually after 20 weeks. It involves high blood pressure and can affect organs like the kidneys and liver, potentially causing problems for both mother and baby.

Why am I taking aspirin in the first place?

Doctors sometimes prescribe a low dose of aspirin to pregnant women who have a higher risk of developing pre-eclampsia, as it can help to prevent the condition.

Will I know which group I'm in?

It's common in studies like this for participants not to know which group they are in (whether they stop aspirin early or continue it) until the study is over. This helps ensure the results are unbiased.

Will this study affect my usual antenatal appointments?

No, your usual antenatal appointments and care will continue as normal. This study will work alongside your existing care, with extra monitoring or data collection as needed.

What if I change my mind about taking part?

You are free to leave the study at any time, for any reason. Your decision will not affect your medical care in any way.