Two series of labour trial were compared in a forward-looking study. The first series of 24 parturient women (series I) to whom the labour trial took place under peridural analgesy. The second series of 80 parturient women (series II) to whom the labour trial took place without peridural analgesy. The rate of caesarean section is significantly less important in the series I (33.3% versus 58%) P = 0.37. The average duration of the labour trial is significantly prolonged under peridural analgesy but without bared effects for the newborn children. The authors consider that the peridural analgesy is the method that brings ideal conditions for a real test allowing to eliminate dynamic dystocia and maternal restlessness in order to have an accurate cephalo-pelvic confrontation.