This is such a common question that it is surprising how little we know about the answer. No one knows exactly how long someone can have vaginal trichomoniasis with few or no symptoms. We do know that women can have this infection for at least three months without symptoms of any kind, and we know that it can be transmitted to a sex partner even when it is causing no symptoms.

The diagnosis of trichomoniasis often raises questions for couples about their partner’s faithfulness. Although trichomonas is always transmitted by sexual contact, the fact that trichomonas can survive for several months, maybe even longer, means that an infection could have been acquired in a previous sexual relationship that ended several months earlier.

It’s also important to remember that men can have trichomonas but almost never have symptoms. And, we know next to nothing about how long some men may have trichomonas. It’s also important to know that making a diagnosis of trichomonas infection in men can be very difficult. Click here to learn more about trichomonas infection.

–J. Dennis Fortenberry, MD, MS