BACKGROUND:Information is routinely given to pregnant women, but information about caesarean birth may be inadequate. OBJECTIVES:To examine the effectiveness of information about caesarean birth. SEARCH STRATEGY:We searched the Cochrane Pregnancy and Childbirth register, CENTRAL (26 November 2002), MEDLINE [online via PubMed 1966-] and the Web of Science citation database [1995-] (20 September 2002), and reference lists of relevant articles. SELECTION CRITERIA:Randomised controlled trials, non-randomised clinical trials and controlled before-and-after studies of information given to pregnant women about caesarean birth. DATA COLLECTION AND ANALYSIS:Two reviewers independently assessed trial quality and extracted data. Missing and further data were sought from trial authors unsuccessfully. Analyses were based on 'intention to treat'. Relative risk and confidence intervals were calculated and reported. Consumer reviewers commented on adequacy of information reported in each study. MAIN RESULTS:Two randomised controlled trials involving 1451 women met the inclusion criteria. Both studies aimed to reduce caesarean births by encouraging women to attempt vaginal delivery. One used a program of prenatal education and support, and the other cognitive therapy to reduce fear. Results were not combined because of differences in the study populations. Non-clinical outcomes were ascertained in both studies through questionnaires, but were subject to rates of loss to follow-up exceeding 10%.A number of important outcomes cannot be reported: knowledge or understanding; decisional conflict; and women's perceptions: of their ability to discuss care with clinicians or family/friends, of whether information needs were met, and of satisfaction with decision-making. Neither study assessed women's perception of participation in decision-making about caesarean birth, but Fraser 1997, who examined the effect of study participation on decision making, found that women in the intervention group were more likely to consider that attempting vaginal birth was easier (51% compared to 28% in control group), or more difficult (10% compared to 6%). These results could be affected by the attrition rate of 11%, and are possibly subject to bias. Neither intervention used in these trials made any difference to clinical outcomes. About 70% or more women attempted vaginal delivery in both trials, yet caesarean delivery rates exceeded 40%, at least 10% higher than was hoped. There was no significant difference between control and intervention groups for any of the outcomes measured: vaginal birth, elective/scheduled caesarean, and attempted vaginal delivery. Outcome data, although similar for both groups, were not sufficient to compare maternal and neonatal morbidity or neonatal mortality. There was no difference in the psychological outcomes for the intervention and control groups reported by either of the included trials. Consumer reviewers said information for women considering a vaginal birth after caesarean (VBAC) should include: risks of VBAC and elective caesarean; warning signs in labour; philosophy and policies of hospital and staff; strategies to improve chances of success; and information about probability of success with specific care givers. REVIEWER'S CONCLUSIONS:Research has focussed on encouraging women to attempt vaginal delivery. Trials of interventions to encourage women to attempt vaginal birth showed no effect, but shortcomings in study design mean that the evidence is inconclusive. Further research on this topic is urgently needed.