Use huawei wristwatch to record maternal rhythm status and record the VAS score after cesarean section under combined spinal-epidural anesthesia. Based on this study the investigators intend to explore the correlation between maternal circadian rhythm status and postoperative pain after cesarean section.
Age 20 to 45
ASA(American society of anesthesiologists) status II-III
37-42 weeks gestation
undergo elective cesarean section with subarachnoid anesthesia
Patients with contraindications of combined spinal and epidural anesthesia
Patients with severe systemic disease
Alcoholism and long-term use of anti-inflammatory and analgesic drugs
Patients who were unable to cooperate or refused to participate in the trial