Landmark Parkland study could reshape how hospitals treat preeclampsia
Study links early aspirin to 26% lower rate of severe pregnancy complications
A new study led by researchers at Parkland Health and the University of Texas Southwestern Medical Center could reshape the way doctors think about preventing one of pregnancy's most dangerous and common complications.
Preeclampsia is a pregnancy complication involving dangerously high blood pressure that can lead to seizures, stroke or death for the mother or baby if left untreated. The only treatment is delivery, which means severe cases often force early or emergency births. It remains one of the leading causes of pregnancy-related death in the nation.
The study, first published in the American Journal of Obstetrics & Gynecology in August, found that prescribing every pregnant patient a daily low-dose aspirin tablet at their first prenatal visit instead of only prescribing it to patients flagged through traditional risk screening led to a significant drop in severe preeclampsia.
Researchers examined more than 36,000 deliveries at Parkland Memorial Hospital from 2020 to 2025, comparing outcomes before and after Parkland began directly dispensing 162 mg of aspirin daily to all patients who started prenatal care by 16 weeks of pregnancy.
After Parkland began giving aspirin to eligible patients in late 2022, severe preeclampsia rates fell by 26%. Preterm birth caused by preeclampsia fell from 4.2% to 2.9%. The change has been implemented across the hospital system ever since.
"We went from 6.9% to 5.1% in cases of severe preeclampsia, which may not sound like a lot, but for a condition this serious, that's a significant change," said Elaine Duryea, MD, Chief of Obstetrics at Parkland and Associate Professor of Obstetrics and Gynecology at UT Southwestern. “And it wasn't just for one group. It worked whether patients had chronic hypertension or not, and across every race and ethnicity we studied."
National guidelines have long recommended aspirin only for patients who have multiple moderate risk factors or one high risk factor using a lengthy risk assessment questionnaire. In 2022, national guidance changed to state that patients with lower incomes should qualify for aspirin without other risk factors, and that health systems serving populations with consistently high preeclampsia rates could skip the questionnaire and offer aspirin to all patients.
Dr. Duryea, who led the study, estimated over 90% of Parkland's pregnant patients qualified for aspirin per these new criteria, so universal aspirin was the best approach.
The drop held across patients with and without chronic hypertension and across every racial and ethnic group studied. Researchers did not find an increase in adverse effects for mothers or babies among the roughly 18,000 women who received aspirin.
The findings were first presented as a late-breaking oral abstract at the Society for Maternal-Fetal Medicine's 2026 Pregnancy Meeting in Las Vegas in February. Dr. Duryea said colleagues from other institutions were eager to take the findings back to their own hospitals, and that the project reflects how Parkland approaches research.
"We are taking known, proven interventions and applying them to our patient population to help improve their health and overcome some of the barriers they might have to achieving good outcomes," she said. "At the end of the day, it's all about taking care of our Dallas County residents and providing them with world-class care."
Parkland is already building on the results through the North Texas Maternal Health Accelerator, a regional healthcare coalition that previously expanded Parkland's iron-dispensing model to clinics across the DFW area. The accelerator is now looking to scale the aspirin program in the same way.
For more information about Parkland services, visit www.parklandhealth.org.
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