The way that people are tested for trichomoniasis is through urine samples or vaginal fluid samples.
For a woman the woman would usually be tested for trichomoniasis through a sample of vaginal fluid and for a man they would be tested for trichomoniasis through a urine sample.
Although some doctors may just want to test for trichomoniasis through a urine sample for both woman and men.
Most people get the parasite that causes trichomoniasis through unprotected sex with someone who has trichomoniasis.
Someone can have trichomoniasis and not know about it and still infect someone else with trichomoniasis.
The parasite that causes trichomoniasis is trichomona which a really tiny parasite that cannot be seen with your naked eye.
To see the trichomona parasite you would need a good microscope.
Some things that can spread the trichomoniasis to another person are pre-cum, and vaginal fluids which get on or inside your penis, vulva, or vagina.
If you think you may have trichomoniasis you should see a doctor and get tested.
If you don't know your partner really good or boyfriend or girlfriend really good then you should use protection when having sex.