Intended for healthcare professionals


Antiplatelet drugs for prevention of pre-eclampsia and its consequences: systematic review

BMJ 2001; 322 doi: (Published 10 February 2001) Cite this as: BMJ 2001;322:329
  1. Lelia Duley (lelia.duley{at}, obstetric epidemiologista,
  2. David Henderson-Smartc, director,
  3. Marian Knightb, specialist registrar,
  4. James Kingd, director
  1. a Resource Centre for Randomised Trials, Institute of Health Sciences, Oxford OX3 7LF
  2. b Health Services Research Unit, Institute of Health Sciences
  3. c New South Wales Centre for Perinatal Health Services Research, Queen Elizabeth II Institute for Mothers and Infants, Sydney, Australia
  4. d Perinatal Epidemiology Unit, Mater Hospital, Brisbane, Australia
  1. Correspondence to: L Duley
  • Accepted 9 November 2000


Objective: To assess the effectiveness and safety of antiplatelet drugs for prevention of pre-eclampsia and its consequences.

Design: Systematic review.

Data sources: Register of trials maintained by Cochrane Pregnancy and Childbirth Group, Cochrane Controlled Trials Register, and Embase.

Included studies: Randomised trials involving women at risk of pre-eclampsia, and its complications, allocated to antiplatelet drug(s) versus placebo or no antiplatelet drug.

Main outcomes measures: Pre-eclampsia, preterm birth, fetal or neonatal death, and small for gestational age baby. Studies were assessed for quality of concealment of allocation and losses to follow up.

Results: 39 trials (30 563 women) were included, and 45 trials (>3000 women) excluded. Use of antiplatelet drugs was associated with a 15% reduction in the risk of pre-eclampsia (32 trials, 29 331 women; relative risk 0.85, 95% confidence interval 0.78 to 0.92; number needed to treat 100, 59 to 167). There was also an 8% reduction in the risk of preterm birth (23 trials, 28 268 women; 0.92, 0.88 to 0.97; 72, 44 to 200), and a 14% reduction in the risk of fetal or neonatal death (30 trials, 30 093 women; 0.86, 0.75 to 0.98; 250, 125 to >10 000) for women allocated antiplatelet drugs. Small for gestational age babies were reported in 25 trials (20 349 women), with no overall difference between the groups (relative risk 0.92, 0.84 to 1.01). There were no significant differences in other measures of outcome.

Conclusions: Antiplatelet drugs, largely low dose aspirin, have small to moderate benefits when used for prevention of pre-eclampsia.


  • Funding None.

  • Competing interests None declared.

  • Embedded Image A table giving details of included studies and full references for included and excluded studies is available on the BMJ's website

  • Accepted 9 November 2000
View Full Text