OBJECTIVE: To assess the effectiveness of hypnosis to reduce pain and facilitate external cephalic version (ECV). DESIGN: Cohort study. SETTING: Geneva University Hospitals, Switzerland. PARTICIPANTS: 63 women attempting ECV under hypnosis from 2010 to 2011 were compared with 122 women who received standard care from 2005 through 2008. INTERVENTION: Immediately after the ECV attempt, both groups completed the same questionnaire evaluating the participants' pain (visual analogue and verbal rating scales) and experience with the procedure. Physicians also completed a questionnaire that elicited their views on the effect of hypnosis on the intervention. A chi-squared test was used to compare differences in proportions, and the Mann-Whitney U test was used for differences in continuous variables. A thematic content analysis of the obstetricians' responses to the open question regarding their experience of hypnotist accompaniment was also performed. OUTCOME MEASURES: Pain evaluated by women (visual analogue and verbal rating scales) and success rate of ECV. RESULTS: Pain intensity reported by women did not significantly differ between the hypnosis group and the standard care group (visual analogue scale score, 6.0 versus 6.3, respectively; p=.25; difference for verbal rating scale, p=0.31. In 72% of cases, physicians reported that hypnosis facilitated the procedure. The success rates in both groups were not significantly different (30% with hypnosis compared with 38% without; p=.31). Most women in both groups found the ECV attempt painful and a source of anxiety but would undergo it again if necessary. CONCLUSION: Hypnosis accompaniment during ECV does not reduce pain intensity associated with the procedure or improve the probability of a successful version.