Tympanic versus rectal thermometry in pregnant women.

OBJECTIVE To assess the accuracy of the tympanic membrane thermometer for use with pregnant women. DESIGN Cross-sectional descriptive study. SETTING A major medical center in the midwestern United States. PARTICIPANTS Thirty-three hospitalized, afebrile pregnant women. MAIN OUTCOME MEASURES Tympanic membrane thermometers and glass mercury thermometers were used to measure body temperature at the ear and rectum, respectively. The results were compared using two statistical methods: the Pearson correlation coefficient and a new technique suggested by Bland and Altman (1986). RESULTS Auditory canal temperature measured by a tympanic membrane thermometer correlated with rectal temperature as measured by a glass mercury thermometer (r = 0.38, p = 0.01). Thus, the tympanic membrane thermometer is acceptable for monitoring the body temperature of pregnant women. However, the device's estimation of rectal temperature is not clinically reliable. CONCLUSIONS Tympanic membrane thermometers, when applied with direct measures, are acceptable for use with pregnant women. It is not recommended that the rectal estimate mode be used with pregnant women.