The secretions collected on the swab are examined under a microscope, cultured, or tested with molecular assays to detect the presence of Trichomonas vaginalis. A culture has greater sensitivity than microscopic examination; molecular assays increase detection over culture due to greater sensitivity.

Your doctor may order the test if you complain of symptoms, such as foul-smelling vaginal discharge or pain on urination. If you have an infection with another sexually transmitted disease, your doctor might test for trichomonas as well.

A positive test indicates an active infection that requires treatment with a course of antibiotics.

Trichomonas is one of the most common sexually transmitted diseases. It infects an estimated 2 million women in the United States each year, mainly those who are 16–35 years old.

An infected person is at greater risk of getting other sexually transmitted diseases, so the doctor may want to test for these other infections also.

Trichomonas infection can affect pregnancy, contributing to premature birth and low birth weight. You should inform your physician if you may be pregnant. The doctor may medically manage a woman who is infected and in her first three months of pregnancy differently.