Objective: To assess the analgesic effect of bilateral ultrasound-guided transversus abdominis plane- block (TAP) with bupivacaine compared with ropivacaine among pregnant woman undergoing a cesarean section. 

Methods: In this study, 60 parturient scheduled for cesarean section randomly received either 20 ml of 0.25% bupivacaine (n=21) or ropivacaine 0.375 % (n=39) in the transversus abdominis plane on each side at the end of surgery. The clinical endpoints such as pain intensity, time to the first analgesic requirement, number of pain medication used and nausea, vomiting, were measured at 2, 8, 12, 24, and 48 h following TAP block. 

Results: Both 0.375% ropivacaine and 0.25% bupivacaine showed a significant reduction in pain intensity. However, there was no statistically significant difference between the groups in pain intensity. Time for first rescue analgesia was seen first in patients under bupivacaine group than ropivacaine group. There was no significant difference in a number of analgesic doses between both the groups. Side effects like nausea and vomiting were comparable. 

Conclusion: Both 0.375% ropivacaine and 0.25% bupivacaine were safe and efficient in TAP blocks in parturients undergoing caesarian section. Time for first rescue analgesia was shorter in bupivacaine group compared to ropivacaine group.