title: Aspirin in the prevention of pre-eclampsia in high-risk women: a randomised placebo-controlled PREDO Trial and a meta-analysis of randomised trials.
abstract: OBJECTIVE
  To study the effect of aspirin in the prevention of pre-eclampsia in high-risk women.
  
  
  METHODS
  Randomised, double-blinded, placebo-controlled trial.
  
  
  METHODS
  Maternity clinics in ten Finnish hospitals participating in the PREDO Project.
  
  
  METHODS
  A total of 152 women with risk factors for pre-eclampsia and abnormal uterine artery Doppler velocimetry.
  
  
  METHODS
  Participants were randomised to start either aspirin 100 mg/day or placebo at 12 + 0 to 13 + 6 weeks + days of gestation. Because of the limited power of this trial, we also conducted a meta-analysis of randomised controlled trials that included data on 346 women with abnormal uterine artery Doppler flow velocimetry, and aspirin 50-150 mg/day started at or before 16( ) weeks of gestation.
  
  
  METHODS
  Pre-eclampsia, gestational hypertension and birthweight standard deviation (SD) score. Outcome measures for the meta-analysis were pre-eclampsia, severe pre-eclampsia, preterm (diagnosed <37 + 0 weeks of gestation) and term pre-eclampsia.
  
  
  RESULTS
  From the 152 randomised women, 121 were included in the final analysis. Low-dose aspirin did not reduce the rate of pre-eclampsia (relative risk [RR] 0.7, 95% CI 0.3-1.7); gestational hypertension (RR 1.6, 95% CI 0.6-4.2); early-onset pre-eclampsia (diagnosed <34 + 0 weeks of gestation) (RR 0.2, 95% CI 0.03-2.1); or severe pre-eclampsia (RR 0.4, 95% CI 0.1-1.3); and the results were not statistically significant in an intention-to-treat analysis. However, our meta-analysis, including the current data, suggested that low-dose aspirin initiated before 16 weeks of gestation reduces the risk of pre-eclampsia (RR 0.6, 95% CI 0.4-0.8) and severe pre-eclampsia (RR 0.3, 95% CI 0.1-0.7).
  
  
  CONCLUSIONS
  Our trial showed no statistically significant effect of aspirin in preventing pre-eclampsia in high-risk women. However, our meta-analysis suggested that aspirin may reduce the incidence of pre-eclampsia.
authors.affiliation: Research Programmes Unit, Women's Health, University of Helsinki, Helsinki, Finland. pia.villa@helsinki.fi
authors.forename: P M
authors.initials: PM
authors.lastname: Villa
authors.forename: E
authors.initials: E
authors.lastname: Kajantie
authors.forename: K
authors.initials: K
authors.lastname: Räikkönen
authors.forename: A-K
authors.initials: AK
authors.lastname: Pesonen
authors.forename: E
authors.initials: E
authors.lastname: Hämäläinen
authors.forename: M
authors.initials: M
authors.lastname: Vainio
authors.forename: P
authors.initials: P
authors.lastname: Taipale
authors.forename: H
authors.initials: H
authors.lastname: Laivuori
mesh_terms: D000293:Adolescent; D000328:Adult; D001241:Aspirin / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D005387:Finland; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D011225:Pre-Eclampsia / Q000000981:diagnostic imaging / Q000517:prevention & control*; D011247:Pregnancy; D018566:Pregnancy, High-Risk; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome; D018615:Ultrasonography, Doppler, Color; D055815:Young Adult
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin