Association between epidural analgesia during labor and fever.

BACKGROUND: Epidural analgesia has been associated in previous research with an increase in maternal temperature.
METHODS: Three studies were done: a retrospective chart review of women in labor, a prospective cohort study of women in labor, and a case-control study of newborns with fever. The prospective study enrolled 28 women, 14 of whom received epidural analgesia. Maternal temperature was measured hourly with a tympanic membrane thermometer. Other variables examined included duration of labor, duration of ruptured membranes, and room temperature. To further explore the possible association between maternal epidural exposure and newborn fever, a case-control study of newborns with fever at birth was carried out.
RESULTS: In both the retrospective and prospective studies of women in labor, the duration of epidural analgesia was correlated with maximum maternal temperature during labor, with an increase, in the prospective study, of 0.07 degrees C per hour of exposure to epidural analgesia (P = .002). Controlling for other variables did not change the magnitude of this effect or its statistical significance. Similar trends were seen in the newborn's first temperature in both the prospective study of women in labor and the case-control study of newborns, but the associations were not significant (P = .07 and .08, respectively).
CONCLUSIONS: Epidural analgesia is associated with an increase in maternal temperature during labor and possibly with an elevation of newborns' first temperatures.