Were used to calculate the size of the sample study data Antalon et al. (2001), who also compared the two techniques of caesarean section, and the Student's t-test was used bi flow. Considering a standard deviation of 1.5 points in the Visual Analog Pain Scale, and significant a difference of two points, the calculated number of patients per group was 15, with a significance level of 5% and power of 95 test %.