title: Combined vitamin C and E supplementation during pregnancy for preeclampsia prevention: a systematic review.
abstract: The effect of combined vitamin C and E supplementation during pregnancy on the prevention of preeclampsia and major adverse infant outcomes has been reviewed. We searched MEDLINE and the Central Library of Controlled Trials of the Cochrane Library through August 2006 for relevant clinical trials. Interstudy heterogeneity was evaluated using the chi(2) statistic (Q statistic) test. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated with a fixed or random-effects model as appropriate. Four trials that collectively randomized 4680 pregnant women to either the combination of vitamin C and vitamin E or placebo were included in the analysis. There were no significant differences between the vitamin and placebo groups in the risk of preeclampsia, 11% versus 11.4%, RR 0.97 (95% CI 0.82-1.13), fetal or neonatal loss, 2.6% versus 2.3%, RR 1.10 (95% CI 0.78-1.57), or small for gestational age (SGA) infant, 20.6% versus 20%, RR 0.94 (95% CI 0.74-1.19). Although there was a higher risk for preterm birth in the vitamin group, 19.5% versus 18%, RR 1.07 (95% CI 0.96-1.20), this finding was not significant. Combined vitamin C and E supplementation during pregnancy does not reduce the risk of preeclampsia, fetal or neonatal loss, small for gestational age infant, or preterm birth. Such supplementation should be discouraged unless solid supporting data from randomized trials become available.
  
  
  BACKGROUND
  Obstetricians & Gynecologists, Family Physicians
  
  
  OBJECTIVE
  After completion of this article, the reader should be able to recall that many methods have been used to prevent preeclampsia, state that increased oxidative stress has been postulated and many trials have used antioxidants to prevent the disease, and explain that MEDLINE analysis of the literature questions the use of vitamin C and E supplements.
authors.affiliation: Section of Obstetrics and Gynaecology, PanHellenic Association for Continual Medical Research (PACMeR), Athens, Greece. n.polyzos@gmail.com
authors.forename: Nikolaos P
authors.initials: NP
authors.lastname: Polyzos
authors.forename: Davide
authors.initials: D
authors.lastname: Mauri
authors.forename: Maria
authors.initials: M
authors.lastname: Tsappi
authors.forename: Spyridon
authors.initials: S
authors.lastname: Tzioras
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Kamposioras
authors.forename: Ivan
authors.initials: I
authors.lastname: Cortinovis
authors.forename: Giovanni
authors.initials: G
authors.lastname: Casazza
mesh_terms: D000975:Antioxidants / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000627:therapeutic use*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D011225:Pre-Eclampsia / Q000517:prevention & control*; D011247:Pregnancy; D011256:Pregnancy Outcome; D018566:Pregnancy, High-Risk / Q000187:drug effects; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment / Q000706:statistics & numerical data; D014481:United States; D014810:Vitamin E / Q000627:therapeutic use*
chemical_list: D000975:Antioxidants; D014810:Vitamin E; D001205:Ascorbic Acid