Aspirin Discontinuation in High-Risk Pregnant Women of Preeclampsia

Study Overview
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Brief Summary
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Low-dose aspirin (LDA) is considered to be the most effective agent to prevent preeclampsia (PE). At present, there is little exploration about the timing of aspirin discontinuation. Most international guidelines default until 36 weeks of gestation or delivery. China Guideline (2020) recommended that aspirin should be preventively used until 26-28 weeks of gestation, but there was little direct evidence. According to the two-stage theory, placental dysplasia before 28 weeks of gestation is the key to developing PE, the significance of aspirin use after 28 weeks of gestation is debatable. If aspirin discontinuation at 28 weeks of gestation is proven to be feasible for preventing preterm PE, it will not only reduce the risk of Perinatal Haemorrhage but also save medical expenses.

Detailed Description
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This study aimed to optimize the strategy of aspirin to prevent preeclampsia, by exploring whether aspirin discontinuation at 28 weeks of gestation to prevent preterm PE is not inferior to 36 weeks of gestation. We will include pregnant women with normal NT scan who meet at least one high-risk factor or at least two medium-risk factors. During 12-16 weeks of gestation, the mean arterial pressure (MAP) and placental growth factor (PlGF) are measured, then initiating aspirin 100mg qn. At 24-27+6 weeks of gestation, the patients were 1:1 randomly divided into two groups, sFlt-1 and PlGF were detected at the same time. The experimental group discontinue aspirin at 28 weeks of gestation, and the control group receive aspirin until 36 weeks of gestation. The incidence of preterm PE in the two groups was compared by non-inferiority test, and the non-inferiority threshold was 2%.

Official Title
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Aspirin Discontinuation at 28 or 36 Weeks' Gestation in High-Risk Pregnant Women of Preeclampsia A Randomized Clinical Trial

Conditions
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Preeclampsia, Perinatal Haemorrhage

Intervention / Treatment
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* Drug: aspirin discontinuation
* Drug: aspirin continuation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: At <16 weeks of gestation, normal NT scan At least 1 high risk factor or at least 2 moderate risk factors Intend to receive prenatal examination and deliver in this institution Signed a written informed consent for participation in the study Exclusion Criteria: Aspirin initiated after 16 week Intolerant or allergic to aspirin Aspirin adherence was <80% Miscarriage or termination of pregnancy before randomization drop out (do not return to the hospital for delivery). Lost to follow-up

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Pregnant women with normal NT scan who meet at least one high-risk factor or at least two medium-risk factors are included. Initiating aspirin 100mg qn during 12-16 weeks of gestation. At 24-27+6 weeks of gestation, the patients were 1:1 randomly divided into two groups. The experimental group discontinue aspirin at 28 weeks of gestation, and the control group receive aspirin until 36 weeks of gestation.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Aspirin discontinuation group<br>initiation of aspirin 100mg qn from 12 to 16 weeks of gestation, receiving 1:1 randomized grouping at 24-27+6 weeks of gestation, discontinuing aspirin at 28 weeks of gestation. | Drug: aspirin discontinuation<br>* Initiation of aspirin 100mg qn from 12 to 16 weeks of gestation, discontinuing aspirin at 28 weeks of gestation according to randomization at 24-27+6 weeks of gestation.<br>* Other names: initiation of aspirin in early pregnancy;|
| Active Comparator: Control group<br>initiation of aspirin 100mg qn from 12 to 16 weeks of gestation, receiving 1:1 randomized grouping at 24-27+6 weeks of gestation, continuing aspirin until 36 weeks of gestation. | Drug: aspirin continuation<br>* Initiation of aspirin 100mg qn from 12 to 16 weeks of gestation, continuing aspirin until 36 weeks of gestation according to randomization at 24-27+6 weeks of gestation.<br>* Other names: initiation of aspirin in early pregnancy;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of preterm preeclampsia | delivery with preeclampsia before 37 weeks of gestation | Within one week after delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of early-onset preeclampsia | delivery with preeclampsia before 34 weeks of gestation | Within one week after delivery | 
| Incidence of term preeclampsia | delivery with preeclampsia after 37 weeks of gestation | Within one week after delivery | 
| Incidence of gestational hypertension | new onset of high blood pressure after 20 weeks of gestation (systolic blood pressure ≥140 mm Hg and/or diastolic blood pressure ≥90 mm Hg) | Within one week after delivery | 
| Incidence of small for gestational age | birth weight below the 10th percentile | Within one week after delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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low dose aspirin, prevention, preeclampsia, pregnancy outcomes, randomized controlled trial, aspirin discontinuation