Trends and Disparities in the Utilization of Low-Dose Aspirin for Pregnancies with Moderate or High-Risk of Preeclampsia: A National Study

Abstract

Background and Objective:

Preeclampsia (PE), a hypertensive disorder of pregnancy, is a leading cause of maternal morbidity and mortality globally. Low-dose aspirin (LDA) is recommended for PE prevention in high- and moderate-risk women. Despite clinical trial evidence, adherence to LDA guidelines and disparities in usage remain underexplored in real-world settings. This study assesses LDA initiation rates among high- and moderate-risk pregnant women, examining disparities by race, geography, and hospital characteristics.

Methods:

We conducted a retrospective cross-sectional analysis of the U.S. Nationwide Inpatient Sample (2016–2021). Pregnancy-associated hospitalizations were identified using International classification disease-10 (ICD-10) codes, and PE risk factors were classified as high or moderate based on the United States Preventive Services Task Force and American College of Obstetricians and Gynecologists criteria. Statistical analyses included descriptive statistics, bivariate analyses, and joinpoint regression to evaluate temporal trends and disparities in LDA use.

Results:

Among 23,163,717 hospitalizations, 8.2% were high-risk and 13.3% moderate-risk for PE. LDA use increased across all groups from 2016 to 2021, but remained lower among moderate-risk women. Racial disparities were evident, with Black and Hispanic women in the moderate-risk group demonstrating lower LDA utilization compared with White women. Geographic disparities revealed the Midwest and Northeast leading in LDA use, whereas rural hospitals consistently reported the lowest rates. Urban teaching hospitals had higher LDA use compared with rural and nonteaching hospitals.

Conclusion:

LDA use for PE prevention has improved, but significant disparities persist by race, region, and hospital type. Provider education, capacity-building in underserved areas, and enhanced documentation are essential to ensure equitable access to this evidence-based intervention.