Having anal warts is not necessarily caused by gay sex. I am a female and I was recently diagnosed with HPV which is also known as genital warts which can be on the anus or in the clitoris...my doctor said that the warts can spread so she figured that my boyfriends penis must have rubbed against my rectum since we have never had anal sex. Anal warts are contagious, i've been with my boyfriend for over 3 years and the warts just showed up...most of the time they show up when your immune system is low...in order to prevent breakouts you must be healthy...i recently had a pap smear which came out normal before my breakout so im not sure how to detect if you have it unless you have visual signs..you can type in HPV onto google and you'll find out a lot of information on anal warts. hope this helps.