Sex and disgust are basic, evolutionary relevant functions that are often construed as paradoxical. In general the stimuli involved in sexual encounters are, at least out of context strongly perceived to hold high disgust qualities.
Saliva, sweat, semen and body odors are among the strongest disgust elicitors. This results in the intriguing question of how people succeed in having pleasurable sex at all.
One possible explanation could be that sexual engagement temporarily reduces the disgust eliciting properties of particular stimuli or that sexual engagement might weaken the hesitation to actually approach these stimuli, according to new results reported in the open access journal PLOS ONE which suggest that this phenomenon may result from sexual arousal actually dampening humans' natural disgust response.
The authors of the study, led by Charmaine Borg of the University of Groningen in the Netherlands, asked female participants to complete various disgusting-seeming actions, like drinking from a cup with an insect in it or wiping their hands with a used tissue. (The participants were not aware of it, but the insect was made of plastic and the tissue was colored with ink to make it appear used.)
Sexually aroused subjects responded to the tasks with less disgust than subjects who were not sexually aroused, suggesting that the state of arousal has some effect on women's disgust response.
Citation: Borg C, de Jong PJ (2012) Feelings of Disgust and Disgust-Induced Avoidance Weaken following Induced Sexual Arousal in Women. PLoS ONE 7(9): e44111. doi:10.1371/journal.pone.0044111