I agree with your basic assessment of the effectiveness of PrEP; and even without PrEP, your partner's PEP makes the risk of transmission -- even with unprotected anal sex, either top or bottom -- also is nearly 100% protective all by itself. And I think you probably can be completely certain your partner will carefully follow his drug regimen. For those reasons, I agree with your doctor: this would be a virtually zero risk situation for you, even without condoms. In fact, you could even consider stopping PrEP -- although of course that also would assume your sexual relationship is and will remain mutually monogamous. Either way, of course you can consider condoms as well.

This is a perfect situation for what is called "shared decision making" between a patient and his physician; and, when a couple is involved, a three way decision process. Although since your partner is a physician himself -- and he's probably as up to speed as a fully trained ID/HIV specialist -- perhaps just the two of you. In any case, your basic thinking is entirely correct. Perhaps your and your partner's mutual decision will come down to your psychological/emotional comfort. When discussing it with him, also keep in mind that true 100% prevention may not be the only goal here:  sexual health involves rewarding sex without undue stress, and some couples in your situation might be willing to accept a small risk of HIV transmission.

In other words, I'm not going to give you a conclusive recommendation about what is best for you and your partner. It's up to the two of you, perhaps with your and his doctor as well (or both of them). But all things considered, I would say unprotected anal sex (in both directions) would be entirely safe, especially with both of you on reliable ARV treatment.

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

HHH, MD

You've been answering my questions on these forums for the past 15 years, and this is the first that hasn't been about an irrational nonexposure fear.  Although it's ironic that I'm falling in love with an HIV positive partner, I really am thankful -- not only for finding someone with whom I can build a romantic relationship -- but for the scientific advances that have resulted in medicine that protects me from infection and allows him to engage in sex without fear of transmission to his partner.  

I appreciated your thoughtful answer since it reiterates scientific truth, but also touches on important things in a relationship like trust, sexual fulfillment, and responsible, consensual decision making.  While my partner is only two years into his residency, he's a brilliant, level-headed, compassionate physician and would never advise explicitly against condoms (just as you wouldn't).  But reading between the lines of conversations with him, my doctor, and you, I think insistence on condoms and intrusive, paranoid questions to him about his undetectable status (when I already know he prioritizes his health and takes his ARV daily) do not change my risk: "virtually zero."  And if I want to grow romantically with him, I have to continue to get over my fear that developed as a young boy growing up in the 80s and 90s.  I'm in therapy, on a low-dose SSRI, and highly motivated to continue my relationship with him!