The goal of this study is to assess the effect of an electronic health record (EHR) clinical decision support tool, also known as a best practice alert (BPA), on healthcare provider recommendations for low dose aspirin use in a high-risk pregnant patient population. The investigators hypothesize that the implementation of the EHR BPA tool will increase the healthcare provider's recommendation for low dose aspirin compared to current standard care.

Low dose aspirin (LDA) has been found to reduce the incidence of preeclampsia in high-risk pregnant patients. At a health system serving central and northeastern Pennsylvania, electronic health record data reveal that clinicians recommend an LDA regimen to only 60% of eligible high-risk pregnant patients, suggesting the need and opportunity for increased LDA recommendation. This study will assess the efficacy of an electronic health record based clinician-facing interruptive clinical decision support tool/best practice alert (BPA) aimed at increasing LDA recommendation for pregnant patients who are at high risk of preeclampsia.

Up to 704 patients will be randomized to account for possible 10% miscarriage and early termination rate as we require outcome data on a total of 640 patients for adequate power. Eligible patients will be randomized to a control group, where the clinician receives no BPA, and one experimental group, where the provider receives a BPA noting the patient is at high-risk and recommend the provider order LDA. If LDA is not recommended, there will be a required acknowledgment reason from the provider noting a rationale for not initiating a LDA regimen.

Inclusion Criteria:

• Receiving prenatal care within Geisinger
• Initial prenatal visit prior to 28 weeks gestation
• Determined to be high risk for preeclampsia based on the modified United States Preventive Services Task Force and American College of Obstetrics and Gynecology criteria (at least 1 high risk factor)

Exclusion Criteria:

• Not pregnant
• No prenatal visit prior to 28 weeks gestation
• Maternal-Fetal Medicine only visits
• Not meeting the modified USPSTF high-risk criteria
• Contraindication to aspirin, including allergy

We will randomize at level of the patient as to whether or not a BPA will fire when the patient is seen in clinic. Any obstetric care provider who sees a patient that has been randomized to BPA group will receive the alert if indicated. If the alert doesn't fire, the care provider will not be aware as to whether the patient is randomized to the BPA group or whether the alert was not indicated. Clinical investigators and outcomes assessors are blinded.