Every Friday on the blog, I answer people’s questions about sex, love, and relationships. This week’s question comes from a reader of the blog who was curious about why so many heterosexual men are pleasuring themselves to pornography featuring transgender and transsexual performers.
I run a porn blog and I keep getting messages from men wanting to see tranny / shemale porn. I'm assuming these men are all straight-identifying, but maybe that's just my gay-identifying bias. I'm wondering what, if any studies or knowledge is out there about men who are attracted to and watch this kind of material or even look for them in real life? It does absolutely nothing for me, but this particular fetish is unavoidable if you frequent any kind of porn social network and it seems a lot of people are into this. What are your thoughts? Why might this be a turn-on for some, and what does it imply, if anything, about their sexuality?
Thanks for submitting this extremely interesting question!
While the terms “tranny” and “shemale” may be commonly used on porn sites to describe a specific genre of porn, many within the trans community find those terms offensive, so I'll stick to the scientific terms here. You are correct in noting that a large number of men seem to be interested in transgender pornography and, believe it or not, the first psychological research on this topic actually dates back several decades.
The technical term for men who are attracted to feminized men is gynandromorphophilia  (how’s that for a tongue twister?). When I say that these guys are into "feminized" men, I do not mean they are attracted to effeminate males or guys who simply display feminine behaviors; instead, they are attracted to men who physically possess both male and female physical characteristics. Thus, the sexual interests of gynandromorphophiles may include either pre- or post-operative male-to-female transsexuals or male cross-dressers.
Although men with such interests are usually stereotyped as being gay, this could not be further from the truth. In fact, research has found that the vast majority (73%) of men who have sex with male-to-female transsexuals identify as straight or bisexual . Likewise, persons who run transsexual porn sites have reported that most of their clients are straight men and that they have next to no gay audience at all .
Why are some men gynandromorphophiles while others are not? We can’t say with any degree of certainty because relatively few studies have been conducted on this topic. However, research has revealed that, for a lot of these men, the appeal seems to reside in the fact that there is something inherently exotic about transsexuals and that transsexualism represents a unique combination of masculinity and femininity in both appearance and behavior. Here are some remarks made by men about what attracts them to male-to-female transsexuals:
“An exoticness, a uniqueness, something that can’t be obtained elsewhere. They’re just totally unique in their sexuality in that they’re both…men and women and at the same time, neither men nor women. To me that’s my fascination.” 
“I like the girls with a little something extra, you know what I mean.” 
Is gynandromorphophilia a fetish? The jury is still out on that, although some have noted that it co-occurs with other erotic interests such as BDSM with some frequency . For now, the most we can say is that attraction to feminized men is a unique erotic interest that is not uncommon in the male population, there is no reason for it to be pathologized or stigmatized, and, contrary to popular belief, guys who have such interests tend to be masculine themselves and usually do not identify as gay.
For past Sex Question Friday posts, see here. Want to learn more about The Psychology of Human Sexuality? Click here for a complete list of articles or like the Facebook page to get articles delivered to your newsfeed.
 Blanchard, R., & Collins, P. I. (1993). Men with sexual interest in transvestites, transsexuals, and she-males. Journal of Nervous & mental Disease, 181, 570-575.
 Operario, D., Burton, J., Underhill, K., & Savelius, J. (2007). Men who have sex with transgender women: Challenges to category-based HIV prevention. AIDS and Behavior, 12, 18-26
 Escoffier, J. (2011). Imagining the she/male: Pornography and the transsexualization of the heterosexual male. Studies in Gender and Sexuality, 12, 268-281.
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