Symptoms depend on the type of vaginitis a woman has1:
Bacterial vaginosis often causes a thin, milky discharge from the vagina that may have a "fishy" odor. It may also cause itching. Most women have no symptoms and only find out they have it during a routine gynecologic exam.
Yeast infections produce a thick, white discharge from the vagina that can look like cottage cheese. The discharge can be watery and often has no smell. Yeast infections usually cause the vagina and vulva to become itchy and red.
Trichomoniasis can cause itching, burning, and soreness of the vagina and vulva, as well as burning during urination. Some women have a "frothy" gray-green discharge, which may smell bad. Many women have no symptoms.