Daily Aspirin Could Dramatically Cut Severe Preeclampsia

Pregnant patients had a 29% lower rate in developing severe preeclampsia (SPE) after given a daily aspirin, according to research shared at the Society for Maternal-Fetal Medicine (SMFM) at the 2026 Pregnancy Meeting on February 11, 2026.¹

Hypertensive disorders are a leading cause of maternal morbidity and mortality worldwide. According to the US Centers for Disease Control and Prevention (CDC), they were responsible for 7.7% of all pregnancy-related deaths in the United States in 2024.²

“Implementation of directly-dispensed aspirin in this high-risk pregnant population appeared to delay the onset, and for some patients completely prevent the development of preeclampsia with severe features,” said lead investigator Elaine L. Duryea, MD, Associate Professor in the Department of Obstetrics and Gynecology at the University of Texas Southwestern Medical Center in Dallas, and Chief of Obstetrics at Parkland Health. “While we cannot be sure that similar effects will be observed in other patient populations, there was no evidence of harm caused by aspirin administration.” ¹

While low-dose aspirin is known to help high-risk patients when started between 12 and 28 weeks of pregnancy, it is often underutilized; consequently, new guidelines suggest universal application in high-risk populations. Recent research at Parkland Hospital in Dallas decided to evaluate the effectiveness of universal aspirin therapy in reducing preeclampsia.

The study implemented a protocol where 162 mg of daily aspirin was provided to all patients at their first prenatal visit, provided it occurred at or before 16 weeks' gestation. To ensure adherence and overcome common barriers to medication usage, the aspirin was directly dispensed to patients at the prenatal clinics. Investigators then compared the outcomes of 18,457 patients who gave birth between 2023 and 2025 under this universal practice against a similar-sized control group from before the protocol was established.

For the participants who did develop SPE despite treatment, the condition manifested later in pregnancy than it did in the control group. The treatment was also found to be specifically effective for patients with preexisting chronic hypertension, who were less likely to develop SPE when given aspirin. Crucially, the study confirmed the safety of this universal approach, finding no increase in maternal hemorrhage or placental abruption associated with the therapy.

These findings are consistent with longstanding guidance from the US Preventive Services Task Force (USPSTF), which recommends daily low-dose aspirin (81 mg) after 12 weeks’ gestation for pregnant people at high risk for preeclampsia, assigning the intervention a Grade B recommendation. The Task Force cites evidence that aspirin reduces the risk of preeclampsia and related morbidity and mortality in high-risk populations, including those with a history of preeclampsia, multifetal gestation, or chronic conditions such as hypertension and diabetes.

Of note, the Parkland study used a higher does aspirin than what the USPSTF recommends but received similar findings. The Parkland study’s observed reduction in severe preeclampsia, particularly among patients with chronic hypertension, reinforces the clinical rationale underlying the USPSTF recommendation and suggests structured implementation strategies, such as direct dispensing, may help address persistent gaps in real-world uptake of this evidence-based preventive therapy.

References:

1. New study: Routine aspirin therapy prevents severe preeclampsia in at-risk populations. EurekAlert! Published February 11, 2026. https://www.eurekalert.org/news-releases/1115004

2. CDC. Data from the Pregnancy Mortality Surveillance System. Maternal Mortality Prevention. Published April 29, 2025. https://www.cdc.gov/maternal-mortality/php/pregnancy-mortality-surveillance-data/index.html?cove-tab=2