Recently, recommendations for the use of low-dose aspirin therapy during pregnancy for the prevention of preeclampsia have expanded and evolved.  These include serial statements from both ACOG and the U.S. Preventive Services Task Force (USPSTF).

The most recent recommendations from the USPSTF cite a potential 24% risk reduction with low-dose aspirin use among women at increased risk for preeclampsia.  Additional literature examining the cost-effectiveness of low-dose aspirin therapy support its use for preventing preeclampsia.

The current USPSTF recommendations provide a potential three-tiered risk category approach to identifying pregnant candidates for low-dose aspirin therapy.  Unfortunately, the clinical utility of this method is somewhat cumbersome.  As such, the MFM providers at Northwest Perinatal Center advocate offering low-dose aspirin therapy for preeclampsia prevention to patients with any of the following diagnoses:

  1. History of preeclampsia leading to preterm delivery;
  2. History of preeclampsia in two prior pregnancies;
  3. Chronic hypertension;
  4. Type 1 or type 2 diabetes;
  5. Renal disease;
  6. Autoimmune disease (e.g. systemic lupus erythematosus, antiphospholipid syndrome); and
  7. Multifetal gestation

While offering low-dose aspirin therapy to patients with several “moderate” level risk factors per the USPSTF guidelines is also reasonable, we focus primarily on the above diagnoses.  We recommend low-dose aspirin therapy (typically 81 mg daily) start after 12 weeks’ gestation and continue until 36 weeks’ gestation.

If you have any additional questions regarding the use of low-dose aspirin for preeclampsia prevention, please contact us.


ACOG. Hypertension in pregnancy: Executive summary. Obstet Gynecol 2013;122:1122-1131.

LeFevre ML. Low-dose aspirin use for the prevention of morbidity and mortality from preeclampsia: U.S Preventive Services Task Force recommendation statement. Ann Intern Med 2014;161:819-826.

Werner EF. A cost-benefit analysis of low-dose aspirin prophylaxis for the prevention of preeclampsia in the United States. Obstet Gynecol 2015;126:1242-1250.