Thermal features of the female axilla

Axillary (Tax), vaginal (Tv), and sublingual (Tsl) temperatures were measured in 12 women between 0600 and 0730 h prior to their arising from bed. Isothermal maps made of closed axilla 30 min after thermojunctions had been inserted showed a distribution of several temperatures, the lowest Tv-Tax isotherm occupying approximately 40% of the anteroposterior distance. Tax at this point was 0.1 to 0.5 degrees C less than Tv and -0.03 to 0.26 degrees C less than Tsl. The time course of Tax rise varied considerably among subjects, with the slowest still rising 30 min after insertion, whereas the fastest was almost steady after 3 min. The width of the 0.5 degrees C isotherm along the fold averaged 5.8 cm and occupied about 60% of the axillary width. A significant negative correlation was noted between width of the 0.5 degrees C isotherm and Tv-Tax. Effects on the time course of 1) preexposure to air of the axilla for 5 min and 2) different initial thermometer temperatures (10 and 30 degrees C) were studied in 6 women. Analysis of variance showed a significantly higher value of Tax (10 min)-Tax (3 min), i.e., a slower time course with the cooler thermometer. The effects of exposure of the axilla were much more pronounced.