Welcome to the forum. I'll try to help.
I think one reason you are fearful is that you are confusing the "population level" predictors of HIV with the "personal level" predictors. What do I mean by that? When considering the entire population, ther are groups of people (population groups) at high risk: gay men, injection drug users, commercial sex workers, etc. And in some areas, including NYC (also Washington DC and most eastern and southern urban areas), the likelihood of HIV in the "general population" is far higher than in, say, Denver, Phoenix, Seattle, or most rural areas. Hence the billboards etc in New York.
But at a personal level, every individual is entrely capable of avoiding HIV. Even among the highest risk population groups, there are individuals who are not at risk at all. They select partners wisely, use condoms, ask their partners about HIV stauts, etc. At a population level, they are "high risk". At a personal level, they are at no risk.
In other words, your risk of catching HIV is mostly within your own control. HIV is not transmitted through condoms. People (and potential partners) generally do not lie about their HIV status. People who get to know their partners before having sex (avoiding one night stands, bar pick-ups, etc) almost never get HIV. In the US, heterosexual men and women who don't pick up casual partners, and who use condoms consistently until a relationship is committed and mutually monogamous, are at extremely low risk of HIV.
In reply to some of your specific questions: Yes, HIV is "really that rare for white heteros to acquire HIV w/o drug use". (In 30+ years in the STD/HIV business, I have never seen a case of HIV in such a person.) I don't think we "dismiss" any fears on this forum -- at least we try not to do so. But the fact is that in the nearly 7 years since this forum and the STD forum were established on MedHelp, there has not been a single case of a user who described a heterosexual encounter, or other low risk encounter, who later came back and said s/he had caught HIV. Not one. (One person claimed to have been infected, but later admitted he had lied.) And no, I have never had a patient not in a high risk category who caught HIV. Can it happen? Yes. But the vast majority turn out to have been at high risk but just didn't know it -- for example, married women who were unaware their husbands were bisexual and having lots of anonymous sex with other men. As for the specific encounters you describe, they do not amount to significant risk for HIV.
So my advice is that you not worry about your partners "ethnically, geographically, lifestyle wise". Just be safe in your own habits. Choose partners who are not drug users, bisexual, etc; don't have one-night stands; ask about HIV status (knowing that most people don't lie when asked directly); and use condoms for new sexual partnerships until mutual monogamy is assured. If you do these things, you can be virtually 100% confident you'll never get HIV.
Do these strategies guarantee no HIV? No. But they make it exceedingly unlikely, certainly below a level that should worry you. Of course it makes sense for all sexually active people (outside mutually monogamous relationships) to have routine HIV testing from time to time. And since you are pregnant, you will have a routine HIV test anyway. You can expect it to be negative.
I hope this helps. Best wishes and happy new year-- HHH, MD
Thanks for the thanks. Glad to help.
Logically, the shorter the exposure, the lower the risk of infection. But there are no data to say how much the chance of transmission is reduced. Maybe not very much.
Thanks a lot- I wanted to say that I applaud you for your approach to everyone on the forum- not that you dismiss fears but you ease them. Most sources tell you if you had any kind of unprotected encounter oral, heterosexual, or otherwise you need an HIV test ASAP- It is nice to see you putting people's risk into perspective. I've been reading this forum for awhile and it helps to ease my fears. Thank you for the advice and happy new year to you as well.
Also, since there is not a lot of information or even questions I have seen a about it, if you have time to clear up the ejaculation vs. no ejaculation dilemma for all of us that would be great. Is a "slip in" encounter just as risky as a full blown sex act?
Thanks!