I had intercourse yesterday using a condom with a "high end" escort in her early 20's, with no apparent STI symptoms. There was no oral sex at all, only brief intercourse in the doggy position using a condom. My question is what would be the likelihood or possibility of HPV transmission in this instance?

I understand that skin-to-skin contact where the condom doesn't reach all the way, such as groin-to-labia, may be a mechanism, but how likely is it? Also I have thick pubic hair, so I'm hoping that helps. Currently, I am asymptomatic. And hope stay that way.

There are no data on the per-exposure risk of HPV infection. But condoms are pretty effective -- only 50% effective over time with repeated vaginal sex exposures, but probably closer to 90% protection for any single event. And even without a condom, most STDs (including HPV) are not transmitted with anywhere near 100% efficiency. In other words, with entirely unprotected sex, the chance you would have been infected undoubtedly was low. Not zero, but low enough that you shouldn't be concerned. I doubt the thickness of your pubic hair makes any difference. 

But the larger issue is that assuming you have had a more or less normal sex life, you can safely assume you have or have had HPV, perhaps repeatedly. Any additional risk from this particular exposure probably is meaningless. We all get HPV, with the rare exception of the permanently abstinent and those with only only one lifetime partner who also never had sex with anyone else -- a rare circumstance in modern western societies. And if and when you or a current or future regular partner ever develops evidence of HPV (most commonly, an abnormal pap smear or appearance of genital warts), there will be no reason to suspect it resulted from this particular commercial sex event.

Before that though, I wanted to point out that you are correct that I had HPV before. It was about 2.5 years ago, along the shaft of my penis, after I had had unprotected intercourse several times over a period of months with a "pro". Setting aside my stupidity, the warts on my shaft were frozen off by liquid nitrogen, never to be seen again. And even after that, I apparently infected my new girlfriend, though she's since cleared it. Nonetheless, I felt guilty.

My questions revolve around the statement in the fist paragraph of your reply, namely that condoms are 50-90% effective depending on repeated vs. single-event vaginal exposures, respectively. Are you actually implying that the HPV viral molecules can penetrate through the physical latex condom barrier?? That would be news to me, and extremely alarming at that. I thought condoms protected the covered surfaces from all matter of bacteria and viruses.  

Lastly, synthesizing your thoughts, is it the case that one exposure to HPV with a condom results very minimal risk of infection, but that a multiplicity of these HPV exposures using condoms would in fact correspondingly multiply the chances for infection?

Thank you,

In regard to your past genital warts, the good news is that having been infected with at least one of the two closely related virus types that cause 90% of warts (HPV 6 and 11), you're probably immune or at least highly resistant to new infection with those types. So regardless of what HPV exposures or infections you have in the future, it is less likely you will develop warts or other symptoms, or have any health impact. (I don't see any evidence of "stupidity" in catching warts, however. Around 20% of all sexually active persons in the US have genital warts at one time or another, so you're not exactly an unusual case!)

All safety devices (seat belts, smoke alarms, etc, etc) are more likely to fail as the number of risk events rises, simply based on probabilities -- the law of averages. In other words, your closing statement is exactly right. If the protection level of condoms is only 90% per use, obviously someone who has used them for 10 similar exposures has a higher chance of HPV or other STDs than for any one use. For HPV, it's all due to skin contact not covered by the condom, improper condom use, breakage, etc. Neither HPV nor any other STD bacteria or virus can pass through latex or polyurethane. Even natural skin condoms have gotten an undeserved bad rap: although in theory viruses etc could pass through their larger pores, in practice it doesn't happen -- i.e. any barrier is better than none.