Fig. 2. Efficacy of epidural injection based on the percentage of parturients experiencing a satisfactory level of analgesia (defined as a score strictly < 30 out of 100 on visual analog scale [VAS]) at different times after injection of the different analgesic solutions. Groups: 150 μg epidural clonidine (C150), 750 μg neostigmine (N750), 75 μg epidural clonidine combined with 250, 500, and 750 μg neostigmine (C75N250, C75N500, and C75N750, respectively). * P < 0.05 with the C75N750 group; + P < 0.05 with the C75N500 and C75N750 group; § P < 0.05 with the C150, C75N500, and C75N750 groups.