Objective To investigate the effect of epidural analgesia for labor and delivery on the association between fever during labor and labor duration. Methods An observational cohort study was performed based on electronic medical record data extracted from the International Peace Maternity and Child Health Hospital from January 2013 and October 2018. The correlation between labor duration and fever during labor was analyzed by regression equation, and the difference in correlation coefficient between the epidural analgesia and non‑epidural analgesia groups was compared. Results Among 37 786 parturient women, epidural analgesia resulted in an increased rate of fever during labor (with an adjusted relative risk of 3.37, P<0.05). The rate of fever during labor was linearly correlated with labor duration in both the epidural analgesia (r=0.909, P<0.05) and non‑epidural analgesia (r=0.777, P<0.05) groups. Furthermore, the correlation coefficient of the regression line in the epidural analgesia group was significantly higher than that in the non‑epidural analgesia group (P<0.05). For women with fever during labor, epidural analgesia did not further increase the risk of maternal or neonatal adverse events. Conclusions For nulliparous women in term pregnancy, their labor during delivery rate is linearly associated with labor duration. Epidural analgesia for labor and delivery can further promote the occurrence of fever during labor.