Related Experiment Video
Updated: Sep 16, 2025
A Novel Method for Involving Women of Color at High Risk for Preterm Birth in Research Priority Setting
Published on: January 12, 2018
Randomised controlled trial comparing low doses of aspirin in the prevention of pre-eclampsia (ASAPP): a study
Amrin Khander1, Kathy Matthews2, Paul Christos3
1Weill Cornell Medical College, New York, New York, USA amk9080@med.cornell.edu.
Insights
This study compares 81 mg versus 162 mg of low-dose aspirin for pre-eclampsia (PEC) prevention in high-risk pregnancies. Findings will guide optimal aspirin dosage for reducing PEC incidence and severe outcomes.
Area of Science:
- Obstetrics and Gynecology
- Pharmacology
- Maternal-Fetal Medicine
Background:
- Pre-eclampsia (PEC) is a serious pregnancy complication, particularly in women with risk factors like hypertension or diabetes.
- Low-dose aspirin (ASA) is the sole prophylactic therapy for PEC, but optimal dosing lacks comparative evidence.
- Current practice involves prescribing 81 mg or 162 mg of ASA without clear guidance on dose-response.
Purpose of the Study:
- To prospectively compare the efficacy of 81 mg versus 162 mg of low-dose aspirin in preventing pre-eclampsia.
- To determine if there is a dose-response relationship for aspirin in PEC risk reduction.
- To evaluate maternal and fetal outcomes associated with different low-dose aspirin regimens.
Main Methods:
- A pragmatic, phase 3, prospective, randomized, open-label, blinded-endpoint trial.
- High-risk pregnant individuals (<16 weeks gestation) were randomized to receive daily 81 mg or 162 mg ASA.
- Primary outcome: incidence of preterm PEC and PEC with severe features; secondary outcomes: adherence, complications, and time-to-event.
Main Results:
- Interim analysis planned after 100 pregnancies to assess feasibility, power, and safety.
- Study follows participants until 6 weeks postpartum, with adherence assessed via questionnaires.
- Intention-to-treat analysis will be employed for final results.
Conclusions:
- This trial will provide crucial evidence on the optimal low-dose aspirin regimen for pre-eclampsia prevention.
- Findings aim to inform clinical decision-making and improve prophylactic strategies for high-risk pregnancies.
- Understanding dose-response can lead to more effective and personalized PEC prevention.
Introduction:
Pre-eclampsia (PEC) is a morbid and potentially lethal complication of pregnancy and is more common in women with risk factors such as hypertension, diabetes, autoimmune disease, kidney disease or multifetal pregnancies. Low dose aspirin (ASA) is currently the only prophylactic therapy known to decrease PEC in this patient population. However, currently, there is no prospective literature comparing various low-dose ASA formulations in the risk reduction of PEC. In the USA, the currently available low-dose ASA is over-the-counter and found in 81 mg tablets. Therefore, when clinicians initiate low-dose ASA therapy, they may prescribe one or two tablets of 81 mg per day without comparative evidence to guide their decision. Our objective is to prospectively compare pregnant patients on 81 mg vs 162 mg of ASA and determine a possible dose response in the prevention of PEC.
Methods And Analysis:
We designed a pragmatic phase 3 prospective randomised open label blinded-end point clinical trial with parallel assignment between two groups of pregnant people at high risk for PEC, as defined by the US Preventive Services Task Force and American College of Obstetricians and Gynecologists (ACOG). The primary outcome is the incidence of preterm (<37 weeks' gestation) PEC and PEC with severe features. Secondary outcomes include adherence to therapy, maternal and fetal complications of PEC, and time-to-event development of PEC across the two treatment groups. Participants are recruited from a tertiary care academic institution and its affiliated community hospital and clinics if they present for prenatal care at <16 weeks' gestation. Women are randomised and accordingly instructed to either take one or two tablets of 81 mg ASA daily. Participants are followed from recruitment until 6 weeks postpartum, with adherence questionnaires collected at 18-22 weeks, 24-28 weeks and 34-38 weeks gestation via a Simple Medication Adherence Questionnaire. After the first 100 pregnancies are completed, a prespecified interim analysis is performed to assess feasibility, tailor power calculations, and ensure safety. The second stage comprises the continuation of recruitment and randomisation to the accrual ceiling as determined by the first stage. Analysis will be completed in an intention-to-treat manner.
Ethics And Dissemination:
Our research protocol and safety monitoring protocol have been approved by the Weill Cornell Medicine institutional review board (IRB) and the Office of Human Research Protection. Evaluation for adverse events will be monitored throughout the study period. Adverse events will be assessed at each study visit.
Trial Registration Number:
NCT04070573.
