Incidence and risk factors for chronic pain after elective caesarean delivery under spinal anaesthesia in a Chinese cohort: a prospective study

Abstract Background China has one of the highest rates of caesarean delivery in the world. The aim of this study was to investigate the incidence and risk factors for chronic pain after caesarean delivery in a Chinese cohort. Methods Patients undergoing elective caesarean delivery with a Pfannenstiel incision under spinal anaesthesia were recruited prospectively at a Chinese tertiary women's hospital. The State Trait Anxiety Inventory was measured before surgery. Postoperative analgesia was provided by intravenous patient-controlled analgesia for 48 hours. Postoperative acute pain scores and analgesic consumption were assessed. After 3, 6 and 12 months, patients were interviewed by telephone regarding whether pain was present, and if present, the intensity, frequency, location and impact of the pain. Results In total 786 patients completed this study. The incidence of pain at 3, 6 and 12 months was 12.2%, 3.8% and 0.8% respectively. Of patients with pain at 3 months, most patients experienced pain daily (43.7%) or with intervals of a day or more between pain (41.7%), with intensity overall described as mild to moderate. The most common sites of pain were the incision or nearby (56.3%), and the low back (36.4%). Risk factors for pain at 3 months included previous caesarean delivery and higher analgesic consumption at 24 h and 48 h postoperatively. Conclusion Chronic pain after elective caesarean delivery under spinal anaesthesia occurs infrequently, especially in the long-term, in a Chinese population. Patients with a previous caesarean delivery and higher analgesic use were at increased risk.