Trichomonas vaginalis is a microscopic parasite found worldwide. In the United States, it is estimated that 2 million women become infected each year.
Trichomoniasis is spread through sexual activity.
Infection is more common in women who have had multiple sexual partners. Typical symptoms include foul smelling or frothy green discharge from the vagina, vaginal itching or redness. Other symptoms can include painful sexual intercourse, lower abdominal discomfort, and the urge to urinate. When symptoms are present, they most commonly are discharge from the urethra, the urge to urinate, and a burning sensation with urination. Most women who develop symptoms do so within 6 months of being infected.