Scared,
If you'd thoroughly searched this site, you'd realise that the ESTIMATED per-act risk for insertive vaginal sex with a KNOWN HIV + person is 2000/1. This statistic comes from the CDC.
Teak informs us that you're close to being banned on Dr. H's forum. You keep posting questions, the answers to which are freely available here and elsewhere. Stop clogging the forum; you had no quantifiable risk, you have the answers to the questions pertaining your own situation. If you keep posting questions, I'm going to report you.
Neither option you posted is correct.
The estimated risk (by the way, it's 1/2000 for insertive vaginal) means that, if millions and millions of HIV- men had unprotected insertive vaginal sex with HIV+ women, enough men would become HIV-infected to have an average transmission risk of approximately 1/2000 (infected men / total men).
Hi scared83, I think 1 in 10000 is the stat given for unprotected receptive oral sex; unprotected vaginal sex is about 1 in 2000.
These stats are generated from long-term studies, normally involving couples, only one of which are HIV positive. An example would be a Ugandan study that showed that over a 4 year period, ~100 couples had, on average, unprotected sex twice a week (=100/year = 400 events of unprotected sex over 4 years) and over that period, 25% of the HIV- partners serocoverted.
This works out as a 1 in 1600 chance of HIV seroconversion per single sexual event as 40000 sexual events resulted in 25 seroconversions over 4 years.
The take home message is that HIV is quite difficult to catch from a single sexual exposure, but that the risk increases with continuous repeated exposures. Makes sense really and explains why HIV seropositivity links with either "risky" behaviour or occurs in long-term relationships when 1 partner is HIV+ and the other is not. In the study above, basically, sleeping 400 times with a HIV positive person over 4 years makes the risk 1 in 4.
Like Teak has said before, always use protection and you'll do fine for the rest of your life!
The stats never include people of unknown HIV status and you would have to multiply any value with the prevalence of HIV in a particular group to work that out.
I dont know why everyone is getting on me. Sure Dr. H said he may ban me if I ask anymore questions but he meant in his thread after he told me I had little risk. But now I'm just asking questions to get educated.
Geez. Fine whatever, I'm gone.