- 51% less likely to use drugs for pain relief (38% of the hypnosis group used pain medications, compared to 74% in the control group)
- 70% less likely to have their labors augmented (11% in the hypnosis group were augmented, compared to 70% in the control group)
- 67% more likely to have a spontaneous vaginal delivery (meaning they were not induced and did not have cesareans)
Despite it being a meta-analysis, the sample sizes are still quite small. As far as I can tell, the control group represents the standard population, which would include women who do not do any childbirth preparation and/or who planned to have epidurals. It would be interesting to see research comparing women using hypnosis with other methods of natural childbirth preparation, since that would provide a clearer picture of the unique benefits of hypnosis.
One reason why hypnosis is such an effective method of birth preparation: research shows women are more easily hypnotized during pregnancy.