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Disgust may be clue to rare sexual disorder

By Stephanie Pappas, LiveScience 

Disgust may play a role in a sexual dysfunction that often renders penetration impossible, new research finds, perhaps revealing a psychological component to physical sexual complaints.

Specifically, women with a disorder called vaginismus are more likely than healthy women or women who have other sexual disorders to feel disgust in response to sexual byproducts such as semen. Vaginismus is a condition in which the pelvic muscles involuntarily contract when penetrated; it often prevents penis-in-vagina intercourse entirely. Though the exact number of women affected is unknown, vaginismus is an uncommon condition, according to the National Institutes of Health.

The new results suggest that involuntary disgust could cause this contraction as a defense mechanism, researchers say.

"In this sense, disgust acts as an emotional equivalent to a cold shower," said Mark van Overveld, a postdoctoral researcher at Erasmus University Rotterdam.

Objectively, van Overveld told LiveScience, sex is a disgusting activity. The bodily fluids and contact with body parts involved are often considered gross or taboo. "From that perspective," van Overveld said, "it is actually quite surprising that people even manage to engage in the act of sexual intercourse at all." 

Disgust itself is a strong emotion, and not one that is easily controlled, as anyone who has ever vomited at the sight of someone else vomiting can attest. But until now, there hasn't been a way to specifically measure sexual disgust, van Overveld said — disgust questionnaires focus on more general questions, like how grossed out you'd be by eating soup that had been stirred by a flyswatter.

The researchers developed a sex-specific questionnaire, focusing largely on questions such as how disgusting it would be to handle someone else's, or one's own, sexual fluids. They first tested the questionnaire on 762 students and university employees to make sure it accurately measured sexual disgust. They found that it did.

Next, the researchers recruited 39 women with lifelong vaginismus, 45 women with dyspareunia, or pain during sexual intercourse, and 28 men with erectile dysfunction and asked them to fill out the questionnaire. [ Top 10 Stigmatized Health Disorders ]

The answers revealed that women with vaginismus were more likely than healthy participants or men and women with other sexual disorders to report disgust for sexually contaminated items. This suggests a role for disgust in either the origin or the continuation of the disorder, van Overveld said.

What's tougher to say is exactly how the emotion plays into the dysfunction. The disgust could come first, triggering the pelvic muscle clampdown. Or perhaps initial sexual problems contribute to disgust with the process, van Overveld said. But disgust is an important defense mechanism, he said, and the pelvic-muscle tightening could be a reflex akin to vomiting.

Previous studies have found that disgust and arousal work in opposition to one another, with sexual arousal dampening disgust. The current study, published online Oct. 22 in the Journal of Sexual Medicine, also found that even in healthy women, more feelings of disgust were linked to fewer feelings of sexual arousal.

The findings shouldn't be taken as blaming women with vaginismus for their condition, van Overveld warned. For one thing, disgust is not easy to control. For another, women with vaginismus have been shown in previous research to have normal sex drives.

However, learning to deal with disgust could potentially help women with vaginismus lessen their condition, van Overveld said. Current experimental therapies have women gradually practice touching their own genitalia, diminishing negative emotions in a controlled way. It's a therapy similar to those used to cure phobias, such as fear of spiders.

"An important next step would be to look at the relationship between disgust and sexual arousal more closely," van Overveld said. "Can sexual intercourse indeed perhaps be interpreted as a delicate balance between disgust on the one hand and a state of sexual arousal on the other? If so, can we help women with lifelong vaginismus to shift this balance?"

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