"Henson et al. (1978) designed a transducer for measuring labial temperature. One thermistor monitors ambient room temperature, another monitors changes in skin temperature at an extragenital site, and a final thermistor is attached to the labia minora using a brass clip. Labial temperature of 9 of the 10 participants in Henson et al.Ős study (1978) increased in response to an erotic film. Slob et al. (1990) and Slob et al. (1991) also found an increase in labial temperature in the majority of participants during the presentation of erotic stimuli. Slob et al. (1990) compared women with and without diabetes mellitus and found initial labial temperatures to be lower in the diabetic women. Differences between the two groups disappeared when participants were matched on initial labial temperature."From Janssen, E., Prause, N., & Geer, J. (2007). The sexual response. In J. T. Cacioppo, L. G. Tassinary, & G. G. Berntson (Eds.), Handbook of Psychophysiology, 3rd ed. New York: Cambridge University Press.