May is Preeclampsia Awareness Month and Lamaze International has a long history of collaborating with the Preeclampsia Foundation to raise awareness with both consumers and perinatal professionals.  Today Rebecca Britt, Community Engagement Manager for the Preeclampsia Foundation shares the latest research and recommendations for low-dose aspirin prenatally to prevent preeclampsia. Do you mention low-dose aspirin in your childbirth education classes? - Sharon Muza, Community Manager, Connecting the Dots

According to American College of Obstetricians and Gynecologists (ACOG) and the U.S. Preventive Services Task Force (USPSTF) guidelines, pregnant people should start taking low-dose prenatal aspirin between weeks 12 and 28 of the pregnancy – but recent evidence shows that starting closer to the beginning of the second trimester may be more beneficial.

A review of 45 randomized trials that included over 20,000 pregnant women taking daily low-dose aspirin showed significant evidence of the prevention of preeclampsia, severe preeclampsia, and fetal growth restriction when initiated before 16 weeks’ gestation. Low-dose aspirin initiated after 16 weeks’ gestation may not be as effective at reducing the risk of preeclampsia, severe preeclampsia, and fetal growth restriction. Women at high risk for those outcomes should be identified in early pregnancy.

When low-dose aspirin is indicated for the prevention of preeclampsia during the prenatal period, most studies are referring to an 81-mg daily tab that is recommended by ACOG. Regular strength aspirin is NOT a preferred pain reliever during pregnancy.

Although there is evidence to suggest that 150 mgs may be more effective, low-dose aspirin is generally available in the United States as 81-mg tablets, which is a reasonable dosage for prevention in people at high risk for preeclampsia.

To prevent all variations of preeclampsia including HELLP syndrome, according to USPSTF guidelines, women with one or more high-risk factors should take low-dose aspirin. Women with several moderate-risk factors may also benefit from low-dose aspirin.

Low-dose aspirin is recommended if the patient has one or more of these high-risk factors:

History of preeclampsia
Multifetal gestation
Chronic hypertension
Type 1 or 2 diabetes
Renal disease
Autoimmune disease (systemic lupus erythematosus, antiphospholipid syndrome)

Low-dose aspirin should be considered if the patient has two or more of these moderate-risk factors:

Nulliparity
Obesity (body mass index >30 kg/m²)
Family history of preeclampsia (mother or sister)
Sociodemographic characteristics (African American race, low socioeconomic status)
Age ≥35 years
Personal history factors (e.g., low birthweight or small for gestational age, previous adverse pregnancy outcome, >10-year pregnancy interval)

Treatment with low-dose aspirin in high- or moderate-risk patients should not decrease regular monitoring and response by the care provider, and the pregnancy should be closely monitored.

As part of its assessment, the USPSTF considered whether there was any potential harm to parent or baby. Its report found:

• No increase in infant loss, growth problems, or cognitive harm to the baby;
• No statistically significant impact on risk of placental abruptions, postpartum hemorrhage (bleeding), or miscarriage to the mother;
• No differences in developmental outcomes of the infants up to age 18 months.
• No studies have followed the offspring of preeclamptic women on aspirin beyond 18 months.

It’s important to note that taking aspirin does not guarantee that at-risk women will not develop preeclampsia, but it’s one more thing they can do with relative safety to reduce their overall risk. The USPSTF review took into account approximately 30,000 randomized subjects, which found a 2 to 5% risk reduction in the rate of preeclampsia. Both the USPSTF and ACOG acknowledge that tools to assess individual risk for the condition and identify subgroups of mothers most likely to benefit are still needed.
 
The USPSTF authors also agreed that preventing preeclampsia could reduce medical intervention in pregnancy and delivery. Preventing poor pregnancy outcomes could also reduce post-traumatic stress disorder and postpartum depression because preeclampsia is associated with poor maternal mental health outcomes.

For more information about prenatal aspirin, visit preeclampsia.org/aspirin.

Patient Education

Ask about Aspirin video

Ask About Aspirin rack card

Frequently Asked Questions about prenatal aspirin

About Rebecca Britt

Rebecca Britt is the Community Education and Engagement Manager for the Preeclampsia Foundation. Her calling to advocate and support those who often don't have a voice led her to earn a Bachelor of Science in Social Work from the University of Vermont.

Rebecca has worked with varying populations including children in foster care, adults surviving with persistent mental illness, and women facing fertility challenges. She is passionate about reducing isolation for preeclampsia patients and survivors by building community connections and raising awareness. Her desire to demonstrate the impact of mission-focused initiatives, lead her to enroll Michigan State University where she is currently earning her Master's Degree in Program Evaluation.

Rebecca is a visionary and global thinker. She is enthusiastic about putting her passion and experience together to unite the preeclampsia community. Upholding the Preeclampsia Foundation's mission, Rebecca aims to provide the education and tools necessary to empower patients to advocate for systemic change to save lives.

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