SMFM recommendation regarding low-dose aspirin prophylaxis for the prevention of preeclampsia. Low-dose aspirin (81 mg/d) prophylaxis is recommended for:
- Pregnant individuals at high risk of preeclampsia with one or more of the following risk factors:
- History of preeclampsia, especially when accompanied by an adverse outcome
- Multifetal gestation
- Chronic hypertension
- Pregestational type 1 or 2 diabetes
- Kidney disease
- Autoimmune disease (ie, systemic lupus erythematous, antiphospholipid syndrome)
- Combinations of multiple moderate-risk factors
These risk factors are consistently associated with the greatest risk for preeclampsia. Preeclampsia incidence would likely be at least 8% in a population of pregnant individuals having one of these risk factors.
- Pregnant individuals with more than one of several moderate risk factors:
- Nulliparity
- Obesity (ie, body mass index > 30)
- Family history of preeclampsia (ie, mother or sister)
- Black race (as a proxy for underlying racism)
- Lower income
- Age 35 years or older
- Personal history factors (eg, low birth weight or small for gestational age, previous adverse pregnancy outcome, >10-year pregnancy interval)
- In vitro fertilization
These factors are independently associated with moderate risk for preeclampsia, some more consistently than others. A combination of multiple moderate-risk factors may place a pregnant person at higher risk for preeclampsia.
Additionally, low-dose aspirin can be considered if the patient has one or more of the following moderate-risk factors: Black race (as a proxy for underlying racism), or lower income. The underlying risk to health is racism and not race. However, there are not yet adequate tools for measuring the known impact of racism on health. Therefore, in this document, Black race serves as a proxy for underlying racism. These factors are associated with increased risk due to environmental, social, structural, and historical inequities shaping health exposures, access to health care, and the unequal distribution of resources, not biological propensities.
When recommended, low-dose aspirin should be initiated between 12 weeks and 28 weeks of gestation (optimally before 16 weeks) and continued daily until delivery
