Aspirin in pregnancy for the prevention of preeclampsia: an evidence-based review

Abstract

Objectives: To review the current evidence for the effectiveness of aspirin in preventing preeclampsia. Data sources: MEDLINE and evidence-based medicine websites. Methods: We searched for clinical practice guidelines (CPG), randomized controlled trials (RCT), systematic reviews (SR) and meta-analyzes (MA), published between 13/11/2005 and 13/11/2015, using the MESH terms ‘pre-eclampsia’ and ‘aspirin’ and the Portuguese DeCS terms ‘pre-eclâmpsia’ and ‘aspirina’. The Strength of Recommendation Taxonomy (SORT) of American Academy of Family Physicians was used for the assignment of levels of evidence (LE) and the strength of recommendations (SOR). Results: A total of 14 articles were selected for this review out of 296 articles found. These included seven MA, three SR, three CPG and one RCT. The SR and MA found benefits for aspirin in the prevention of preeclampsia, particularly in women at high-risk. One SR with LE 2 found no evidence to support the use of aspirin prophylaxis in women at risk for preeclampsia. Studies that analyzed women at low-risk separately found no benefit from the use of aspirin in this group of women. The CPG recommend the use of aspirin in the prevention of preeclampsia in high-risk women and discouraged its use in low-risk women. The RCT supported the same recommendation for high-risk women. Conclusions: The available evidence suggests that low-dose aspirin is effective for the prevention of preeclampsia in women at risk. There is clear evidence of its benefit in high-risk women (SOR A) and its use is discouraged in low-risk women (SOR A). There is still a need for more high quality studies with similar methods conducted in relevant populations to support these recommendations.