Brief Answer:
Possibility of either missed or uninfected is there.

Detailed Answer:
Hi,
Welcome to HCM.
Thanks for posting your query.
Trichomonas vaginalis is a Sexually transmitted disease.
This infection primarily manifest in women and remain asymptomatic in men. Owing to the anatomical nature of women the potential space, pH inside the vagina favors the multiplication of this unicellular parasite. In men it will exist in small number and remains asymptomatic (once again due to anatomical and physiological nature) (Frequent urination- in women the urinary passage and vagina are different). It might have missed to be identified with your boy friend due to its scanty in number.
You had not mentioned more details about the following:
1 Your sexual activities
2. What test had been tested for your boy friend? (Trichomonas might be identified either in urine or semen or prostatic massage fluid on examination)
With a single test we can not declare that he is free from Tichomonas. Repeated examinations (at least 3 examinations) will reveal the same.
In spite of all, still there is a possibility that a partner can remain uninfected (discordant) due to various reasons including natural resistance. Example: All who dines in a hotel not necessarily infected with amoeba while some have been manifestations.
Hope you got the point.
Dr S.Murugan

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