1. Protected sex (assuming condoms don't break etc) is safe sex for all STI's.

2. Unprotected Oral sex where man receives BJ is virtually safe for all STI's - not zero, but as near as for all practical purposes.

3. Unprotected Oral sex (cunnilingus) is totally safe for the woman, and very safe for the giver, not zero, but similar to above, as near as for all practical purposes.

Have I got that about right?

Thanks

Safe sex is relative. Some kinds of contact are zero risk, or so close to zero that any risk can and should be ignored. However, your statements go a bit too far:  all the scenarios you describe are somewhat higher risk than you state, To your questions:

1. People get STIs fairly frequently despite consistent and correct condom use, without condom breakage. Most important, condoms provide incomplete protection against STIs transmitted primarily by skin to skin contact -- i.e. syphilis, HPV, and herpes. This results from skin contact above the condom, and also probably because genital fluids can work their way over the rim and part way inside the condom. As long as the head of the penis and meatus (urethral opening) are covered, risk for HIV, gonorrhea and chlamydia can be considered zero for all practical purposes. Nevertheless, people who report consistent and proper condom use are at increased risk for these STIs as well, probably because "complete and consistent" proper use can be difficult to achieve. Similarly, couples who depend exclusively on condoms for contraception have higher pregnancy rates than those using the pill or other hormonal methods.

2. You also overstate the safety of oral to penile STI transmmission. Gonorrhea, nongonococcal urethritis (NGU), and herpes due to HSV1 are fairly common. The risk of these is low compared with unpotected vaginal or anal sex, however -- but not low enough to be ignored. Oral to penile transmission of HIV has never been scientifically documented -- but perhaps not truly zero risk. Chlamydia, HSV2, and HPV also are extremely rare in this setting.

3. Finally, I would not characterize cunnlingus as "totally" safe for the female partner. Certainly oral to vaginal transmission is uncommon for most or all STIs, but the risk may be substantial for herpes due to HSV1. Vaginal to oral transmission also is rare, but surely not zero risk.

The bottom lilne is that people who participate regularly in such activities with multiple or high-risk partners should be tested periodically for common STIs, especially chlamydia, gonorrhea, syphilis and HIV -- despite regular condom use and no observed condom failures.

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

HHH, MD

If I may ask one last question in relation to (1) and (2) if one assumed that a partner had any of the mentioned STI’s for sake of discussion (I know that’s not the case with the general population), how probable would transmission be, for example would it be 1 in 10 occurrence, or higher or lower? I know that this may be virtually impossible to answer give the range of infections and acts - so was just looking for a general sense of risk?

Noted and (3) and also testing. 

Thanks in advance