Trichomonas is the most common of all STDs, second only to HPV. However, serious outcomes are infrequent; from a public health perspective, it's not nearly as important as chlamydia or gonorrhea. Although there is controversy about it, including whether accurate testing (i.e. NAAT) should be more routine than it is, in general it is not a serious health threat. Having trich elevates the chance of catching HIV if exposed, but this is a minor factor in HIV prevention in industrialized countries.

To your questions:

HHH, MD

The natural course of untreated trichomoniasis has never been formally studied. We know that some women have trich diagnosed despite having had no sexual exposures at all for many years, and these are felt to be from longstanding infection that never cleared up. However, it might be a minority, maybe quite a small minority, of all women who acquire the infection; in other words, most infections may clear up with time. There are even fewer data in men, but most experts believe that such longstanding infections are less common in men than women. But beyond that, we just don't know. (However, when trichomoniasis first appears in a monogamous couple, we advise that because it's sexually transmitted, they should speak with their spouse or partner about the possibility of outside sexual experiences. However, if that is believed to be unlikely, we do not press the point -- quite different than how we counsel couples with gonorrhea, chlamydia or syphliis, for example.

Because of the prior delay, I'll leave this thread open for another round of comment and reply if anything remains unclear. Apologies again for the delayed response.

Best wishes and stay safe.