The information provided here is not a replacement for a doctor. You shouldn't use it for the purpose of self-diagnosing or self-medicating but rather so you can have a more informed discussion with a professional TCM practitioner.
Because it is a herb specifically indicated to treat vaginal protozoa as can be seen on Chinese Pulsatilla Root's page.
Chinese Pulsatilla Roots is a Cold herb that tastes Bitter. It targets the Stomach, the Large intestine and the Liver.
Its main actions are: Expels Heat and Toxicity from the Blood. Clears Damp-Heat in the Lower Burner. Treats vaginal parasites and other conditions such as trichomonas.