Quadratus lumborum block for postoperative analgesia after cesarean delivery: A systematic review with meta-analysis and trial-sequential analysis

•Quadratus lumborum block (QLB) is a truncal block for postoperative analgesia.•Efficacy of QLB in improving post-cesarean delivery analgesia is unknown.•QLB improves pain scores and opioid consumption compared to controls.•QLB has no additional analgesic benefit when used together with neuraxial morphine.•Insufficient data on QLB versus transversus abdominis plane block or neuraxial morphine