Fetal and maternal temperatures during labor and delivery: a prospective descriptive study.

OBJECTIVE: The objective of this study is to study the fetal scalp temperature (FST) and maternal axillary temperature (MAT) during vaginal delivery relative to progression of labor, uterine contractions (UC) and epidural analgesia (EDA), and to construct normal temperature reference ranges related to stage of labor.

MATERIAL AND METHODS: Temperatures were recorded continuously in labor of 132 women with a bi-metal temperature sensor attached to the axilla (MAT) and a similar sensor mounted in a scalp electrode (FST). The temperature data were stored electronically and analyzed offline at cervical dilatations of 2-3, 5, 7-8, and 10 cm, and at full retraction. The FST was read before, at increasing, at peak, at decreasing, and after UC. The MAT and FST curves were compared with mixed-effect models statistics for repeated measurements. A two-tailed p <.05 was considered significant.

RESULTS: The FST did not vary during UC (p = .24). Both FST and MAT increased linearly by progression of labor (both p < .001). The increases in temperatures were greater with EDA than without (p < .001).

CONCLUSIONS: During UC, the FST showed no alteration. Both FST and MAT increased significantly by progression of labor, and significantly more in the presence of EDA. The presented normal temperature reference ranges can be used for future research.