1134 Low dose aspirin administration in all nulliparous women with singleton pregnancy: a cost-effectiveness analysis

Abstract

Preterm birth is a major risk factor for neonatal mortality. Studies show that aspirin decreases the development of preeclampsia in nulliparous women. Additionally, the ASPIRIN trial showed that aspirin initiation between 6 and 13 weeks gestation reduces preterm birth incidence. This study investigates the cost-effectiveness of aspirin initiation in the 1st trimester for prevention of preterm birth in nulliparous women. A cost-effectiveness model using TreeAge 2020 software was designed to compare maternal and neonatal outcomes of aspirin administration versus no aspirin administration in nulliparous women with singleton pregnancies. We used a theoretical cohort of 100,000 women. Outcomes included preterm delivery < 34 weeks, preterm delivery < 37 weeks, maternal death, hypertensive disorders, spontaneous abortion, intrauterine fetal demise, neonatal neurodevelopmental delay, and infant death. All values were derived from the literature. The willingness-to-pay threshold was $100,000/quality adjusted life year (QALY) and QALYs were discounted at a rate of 3%. Sensitivity analyses evaluated the power of our model. In our theoretical cohort, we found that aspirin prophylaxis in the 1st trimester would result in 523 fewer cases of preterm delivery < 37 weeks and 539 fewer cases of preterm delivery < 34 weeks. Additionally, there would be 3,873 decreased cases of hypertensive disorders. Aspirin therapy was the dominant strategy, resulting in increased QALYs and decreased costs, saving $194 million. Sensitivity analyses showed that the results were consistent over a wide range of assumptions. Even if there was less of a reduction in hypertensive disorders (baseline probability 0.057) than predicted with aspirin administration, there was still an impact in reduction of preterm deliveries. Our model found that aspirin initiation during the 1st trimester in all nulliparous women results in decreased rates of preterm delivery. These results are significant as it is cost effective to administer aspirin to all nulliparous singleton women regardless of hypertensive status.View Large Image Figure ViewerDownload Hi-res image Download (PPT)