Efficacy of continuous monitoring of maternal temperature during labor using wireless axillary sensors

Neonatal early onset sepsis (EOS) occurs in 0.5-0.8/1000 live births and is a major cause of morbidity and mortality. Its presenting signs in newborns are non-specific, so risk assessment before birth is essential. Maternal fever during labor is the strongest predictor of EOS, but the current standard is for infrequent manual determinations of temperature. We aimed to determine whether continuous measurement of temperature during labor is feasible, accurate, and more effective than manual measurements for detecting fever. Women were recruited on admission in labor at > 35 weeks gestational age, with < 6 cm cervical dilation. Sensors were affixed in the axilla, which transmitted every 4 minutes by Bluetooth to a dedicated tablet. Conventional temperature measurements were taken every 3-6 hours per routine. Of 336 subjects recruited, 155 had both > 4 hours of continuous data and > 2 manual temperature measurements and were included for analysis. Continuous recordings were feasible and correlated well with manual measurements independent of mean temperature. Of 15 episodes of fever > 38 °C detected by both methods, 13 were detected earlier by continuous (9 of those more than 1 hour earlier). Manual measurements missed 32 fevers > 38 °C and 13 fevers > 38.5 °C that were identified by continuous. Continuous measurement of maternal temperature for the duration of labor is practical and accurate. It may be more sensitive for identifying infants at risk for EOS than the current practice, enabling earlier and more effective targeted treatment of affected infants.