I'm sure you have answered this question countless times before, but I would greatly appreciate if you take the time to consider my particular circumstances.

I am a late-20's male who had a drunken, regrettable one-time encounter with a co-worker six (6) days ago.  She is in her late 30's, white, and says she is clean.  We had brief unprotected oral sex (1-2 minutes, both giving and receiving), followed by brief unprotected vaginal sex (1 minute, before I put a condom on and proceeded for another 2 or so minutes).  I have never tested positive for an STD before, other than oral HSV1 I acquired as a child.  I have been carefully monitoring myself in the intervening time and have had no symptoms or signs of an infection whatsoever.  I went in for a Chlamydia/Gonorrhea test this morning and am awaiting results.  I also plan on returning for Syphilis/HSV2/HIV testing in one month. 

I am simply asking about the possible risks from this encounter.  I had been hoping to begin a relationship with someone else, but I am now worried about exposing her to anything.  How likely is it that I contracted a STD from this encounter, and if I did, how likely it is I can pass it on without being currently symptomatic?

Sincerely and thanks,

Before getting to the details, I'll give a couple of general comments. The large majority of sexual encounters, no matter how risky, do not transmit STDs. Even among the most sexually active populations, at any time most don't have transmissible infections; and all STDs are inefficiently transmitted, i.e. even when one partner is infected, most exposures don't result in transmission. Further, a partner like yours is especially unlikely to have any active STDs. The risk drops dramatically after age 25 and even more at 30 and above; and most women who believe they are uninfected (she "says she is clean") are usually both truthful and accurate.

Now going to the specifics of your exposure:  The only part of this event that gives even a little cause for concern is the unprotected minute of vagnal sex. The oral sex, in both directions, was exceedingly low risk. From a medical or risk perspective, I really don't think any testing at all is necessary.

If somehow I were in your circumstance, I would not be tested and would go ahead with my prospective new relationship without worry. That said, of course nobody can guarantee zero risk. But rather than testing, I would recommend a discussion with your co-worker partner. You may find she is just as concerned as you are about STD risks, perhaps more so (which would be appropriate, since the risks of both catching STDs and having serious outcomes are higher in women than men). If she were continue to confirm that she is likely uninfected and hasn't been at risk recently (i.e. if the experience with you was one-off). Alternatively, if indeed she has had other partners and/or is as concerned as you are, you could both be tested without having to wait a few weeks.

If you go ahead with testing, either on your own or together, only have urine tests (or vaginal swab for her) for gonorrhea and chlamydia and blood tests for HIV and syphilis. The chance of HSV2 from a single encounter like this is exceedingly low, and the HSV blood tests are only fair:  the chance of a false or misleading result is far higher than the possibility that either of you gave HSV2 to the other. If you are the only one tested, the same advice goes, except you can do the gonorrhea/chlamydia test any time more than 4-5 days after the encounter, and should delay the syphilis and HIV tests to 6 weeks (4 weeks is too soon). But even then, I don't think you need delay sex with your potential new partner. The chance of either syphilis or HIV from this event is on the order of one in many million, zero for all intents and purposes.

I hope these comments have been helpful. Let me know if anything isn't clear.

HHH, MD

Thank you very much for your quick and useful reply.  Your conclusions are the same as I had come to based upon my (limited) research.  I have discussed the exposure with the co-worker and she isn't worried at all (I guess I look well-kept?).  Since it has been six days since the encounter, I presume my Chlamydia/Gonorrhea results will be accurate when they arrive and will just continue to self-monitor for any signs of anything else.

I think I'm going to go ahead and have the testing for peace of mind, and I'll go back in for the Syphilis/HIV testing in 6 weeks, per your suggestion.

Again, thank you for your help.  I have come across your comments and responses in this forum and others while researching my odds, and while I'm sure answering these sort of questions must get tedious some times, it really is a great relief to us posters.

Thanks for the thanks. I'm glad to have helped.