Elsevier

Obstetrics & Gynecology

Volume 101, Issue 6, June 2003, Pages 1319-1332
Obstetrics & Gynecology

Review
Aspirin for prevention of preeclampsia in women with historical risk factors: a systematic review

https://doi.org/10.1016/S0029-7844(03)00169-8Get rights and content

Abstract

Objective

To examine the effectiveness of aspirin in preventing perinatal death and preeclampsia in women with predisposing historical risk factors, such as previous history of preeclampsia, chronic hypertension, diabetes, and renal disease.

Data sources

Searches were conducted in MEDLINE, EMBASE, Cochrane Library, National Research Register, SCISEARCH, and ISI Conference Proceedings without any language restriction, using the following medical subject headings and text words: “aspirin,” “antiplatelet*,” “salicyl*,” “acetylsalicyl*,” “platelet aggregation inhibitors,” “pre-eclamp*,” “preeclamp*,” and “hypertens*.”

Methods of study selection

We included all randomized trials that evaluated the effectiveness of aspirin compared with placebo or no treatment in women with predisposing historical risk factors and reported clinically relevant perinatal or maternal outcomes. Study selection, quality appraisal, and data extractions were performed independently and in duplicate.

Tabulation, integration, and results

We identified 14 relevant trials, including a total of 12,416 women. Meta-analysis showed a significant benefit of aspirin therapy in reducing perinatal death (odds ratio [OR] 0.79, 95% confidence interval [CI] 0.64, 0.96) and preeclampsia (OR 0.86, 95% CI 0.76, 0.96). Aspirin was also associated with a reduction in rates of spontaneous preterm birth (OR 0.86, 95% CI 0.79, 0.94), and an increase of 215 g in mean birth weight (weighted mean difference 215, 95% CI 90, 341). There was no increase in the risk of placental abruption with aspirin (OR 0.98, 95% CI 0.79, 1.21). Funnel plot analysis indicated that publication and related biases were unlikely (Egger test, P = .84).

Conclusion

Aspirin reduces the risk of perinatal death and preeclampsia in women with historical risk factors. Given the importance of these outcomes and the safety and low cost of aspirin, aspirin therapy should be considered in women with historical risk factors.

Section snippets

Sources

We searched MEDLINE (1966–2001), EMBASE (1980–2001), Cochrane Library (2001:3), National Research Register (2001:3), SCISEARCH (1974–2001), and conference proceedings (ISI Proceedings, 1990–2001) for relevant citations. A combination of medical subject headings and text words were used to generate two subsets of citations, one including studies of aspirin (“aspirin,” “antiplatelet*,” “salicyl*,” “acetylsalicyl*,” and “platelet aggregation inhibitors”) and the other studies of preeclampsia

Study selection

Studies were selected if the target population was women with historical risk factors for preeclampsia, the therapeutic intervention was low-dose aspirin (any definition) compared with placebo or no drug treatment, and the studies were of randomized design. The historical risk factors included previous preeclampsia, chronic (preexisting) hypertension, diabetes, renal disease, and extremes of age at conception.3, 20, 21 The main outcomes were perinatal death and preeclampsia (proteinuric

Results

Figure 1 summarizes the process of literature identification and selection. Of the 729 citations identified, 47 were selected during the initial screening (agreement 99%; κ 0.91), and on examination of the full manuscripts of these 47, 12 articles,11, 12, 13, 14, 15, 17, 18, 19, 31, 32, 33, 34 and two abstracts (Azar R, Turpin D. Effect of antiplatelet therapy in women at high risk for pregnancy induced hypertension [abstract]. Proceedings of 7th World Congress, International Society for the

Conclusion

Our systematic review shows that low-dose aspirin has a significant effect in reducing the rates of a number of clinically relevant outcomes, including perinatal deaths and preeclampsia, in women with historical risk factors for preeclampsia.

The validity of our findings depends on the methodologic rigor of our review and of the component primary studies. We used a prospective protocol and made a concerted effort to find all the evidence. Two independent reviewers assessed study quality and

References (44)

  • W Visser et al.

    Prediction and prevention of pregnancy-induced hypertensive disorders

    Baillieres Best Pract Res Clin Obstet Gynaecol

    (1999)
  • S Yusuf et al.

    Beta blockade during and after myocardial infarctionAn overview of the randomized trials

    Prog Cardiovasc Dis

    (1985)
  • S.G Thompson et al.

    Can meta-analyses be trusted?

    Lancet

    (1991)
  • R DerSimonian et al.

    Meta-analysis in clinical trials

    Control Clin Trials

    (1986)
  • E Ernst et al.

    Assessment of therapeutic safety in systematic reviewsLiterature review

    BMJ

    (2001)
  • M.A Klebanoff et al.

    Aspirin exposure during the first 20 weeks of gestation and IQ at four years of age

    Teratology

    (1988)
  • W.C Mabie et al.

    Chronic hypertension in pregnancy

    Obstet Gynecol

    (1986)
  • D.C Jones et al.

    Outcome of pregnancy in women with moderate or severe renal insufficiency

    N Engl J Med

    (1996)
  • I Mogren et al.

    Familial occurrence of preeclampsia

    Epidemiology

    (1999)
  • F Parazzini et al.

    Low-dose aspirin in prevention and treatment of intrauterine growth retardation and pregnancy-induced hypertension

    Lancet

    (1993)
  • V.A Rogov et al.

    Acetylsalicylic acid and kurantil in the prevention of pregnancy complications in glomerulonephritis and hypertension

    Ter Arkh

    (1993)
  • L Viinikka et al.

    Low dose aspirin in hypertensive pregnant womenEffect on pregnancy outcome and prostacyclin-thromboxane balance in mother and newborn

    Br J Obstet Gynaecol

    (1993)
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    All contributors to this review, except HH, are employees of the National Health Service of United Kingdom. HH holds a WellBeing Research Fund from the Royal College of Obstetricians and Gynaecologists (United Kingdom). No private or commercial funding was obtained.

    AC and KSK conceived the review. AC, HH, and SP collected, analyzed, and interpreted the data and drafted the manuscript. KSK and HG made critical revisions. AC and HH are the guarantors for this article.

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