Continuous Monitoring of Body Temperature in Mothers and Their Preterm Neonates During the Immediate Postnatal Transition - A Prospective Observational Pilot Study

This is a prospective, multicenter, observational pilot study conducted at the Medical University of Graz, Austria, and the University Hospital Essen, Germany, to evaluate the feasibility, performance, and safety of continuous non-invasive body temperature monitoring using the SteadyTemp® wireless adhesive thermometer in moderately preterm neonates during the immediate postnatal transition. In addition, maternal intrapartum body temperature will be continuously monitored to explore the relationship between maternal and neonatal thermal regulation during the perinatal period.

Maintaining normothermia immediately after birth is a key component of neonatal care, particularly for preterm infants, who are at increased risk of thermal instability because of immature thermoregulation, limited brown adipose tissue, and a high surface area-to-volume ratio. Both hypothermia and hyperthermia are associated with increased neonatal morbidity and mortality. Conventional temperature assessment methods provide only intermittent measurements and do not permit continuous monitoring during the critical transition after birth. The SteadyTemp® adhesive thermometer is a wireless, skin-adherent device that continuously records body temperature and transfers the data via near-field communication (NFC). Although the device has previously been evaluated in adults and term neonates, its feasibility and performance in preterm neonates have not yet been investigated.

Following informed consent before delivery, the SteadyTemp® adhesive thermometer will be applied to the mother at least 10 minutes before birth to enable continuous intrapartum temperature monitoring. Immediately after birth, a second SteadyTemp® adhesive thermometer will be applied to the right axillary region of the preterm neonate and will continuously record body temperature during the first 15 minutes of postnatal transition. After completion of monitoring, the adhesive patch will be removed and neonatal skin integrity will be assessed using the Neonatal Skin Condition Scale (NSCS). As part of routine clinical care, a single rectal body temperature measurement will be obtained using the locally established reference thermometer and used for comparison with the temperature recorded by the investigational device. No study-specific therapeutic interventions are performed beyond application of the adhesive thermometers.

The study plans to enroll 80 participants, comprising 40 mother-preterm neonate pairs. The sample size was determined to provide adequate precision for estimating the feasibility of continuous temperature monitoring based on results from a previous pilot study in term neonates. The study is intended to generate preliminary evidence regarding device feasibility, agreement with routine clinical temperature measurements, skin tolerability, and the relationship between maternal and neonatal temperatures to support the design of future confirmatory studies.

Statistical analyses will primarily be descriptive. Continuous variables will be summarized using means and standard deviations or medians and interquartile ranges, as appropriate, while categorical variables will be presented as counts and percentages. Feasibility will be reported as the proportion of successful uninterrupted temperature recordings with corresponding 95% confidence intervals. Agreement between SteadyTemp® and rectal temperature measurements will be evaluated using Bland-Altman analysis and correlation analysis. Skin tolerability will be summarized descriptively, and changes in skin condition will be assessed when baseline assessments are available. Associations between maternal intrapartum temperature and neonatal temperature during the immediate postnatal transition will be explored using correlation analyses and longitudinal linear mixed models adjusted for relevant clinical variables. Statistical analyses will be performed using R software, and a two-sided p-value <0.05 will be considered statistically significant.