Study’s Findings Support Low-Dose Aspirin As Best Way to Prevent Preeclampsia

New research suggests that more than 86% of pregnant women may benefit from taking low-dose aspirin to help prevent preeclampsia, a serious pregnancy complication that can lead to dire health effects for both mother and child.

Many pregnant women face an increased risk of suffering from preeclampsia, and researchers are now calling for simplified guidelines to be developed that recommend a daily low-dose of aspirin for those facing even a moderate chance of experiencing the complications, according to a report published this week in the medical journal JAMA Network Open.

Preeclampsia causes excess protein in the urine and can lead to high blood pressure during pregnancy. It often occurs in the third trimester or shortly after birth, and can result in liver abnormalities, blood clotting problems, headache, stroke, and even death.

Researchers from Duke University conducted a cohort study using data from more than 3.6 million recorded deliveries in the U.S., including birth certificates from the National Center for Health Statistics and birth records from 2019. According to the findings, nearly 170,000 pregnancies involved one or more high-risk factors for preeclampsia, but nearly 3 million pregnancies had one or more moderate-risk factors.

According to the US Preventive Services Task Force (USPSTF), risk factors for preeclampsia include carrying multiple infants, diabetes, being older than 35, obesity, high blood pressure before pregnancy, kidney disease, and autoimmune disorders. Preeclampsia also occurs more frequently in Black people and people of low-socioeconomic status.

In 2021, the USPSTF recommended low-dose aspirin for those with risk factors for preeclampsia; however, many women are still not receiving this advice from their doctors, researchers said.

The findings of the new study indicate 4.5% of deliveries in 2019 had one or more high-risk factors for preeclampsia, and 81% of deliveries had one or more moderate risks for preeclampsia.

The researchers determined 86% of pregnant patients met the 2021 criteria to take low-dose aspirin to help prevent preeclampsia and more than 92% of pregnancies documented pregnancy-related hypertension in 2019, which is also a risk factor for the condition.

The most common high-risk factor was being pregnant with multiple babies, which occurs in about 3% of patients. Low socioeconomic status was the most common moderate-risk factor and accounted for 47% pregnancies.

The more moderate-risk factors a woman had, the higher the risk they had of suffering from pregnancy-related hypertension. According to the 2021 guidelines, 92% of pregnancies in the study should have led to low-dose aspirin recommendations because of the risk of pregnancy-related hypertension.

“Preeclampsia is an important cause of maternal and fetal morbidity and mortality, and LDA (low-dose aspirin) is one of very few evidence-based preventions,” the researchers wrote. “Given the high prevalence of risk factors for preeclampsia and the complexity of existing guidelines, further consideration of expanding definitive LDA recommendations to individuals with at least 1 moderate-risk factor, or simply universal LDA for all pregnant individuals, is needed.”