Vaginal Wet Mount
A vaginal wet mount (sometimes called a vaginal
smear) is a test to find the cause of vaginitis, or inflammation of the vagina
and the area around the vagina (vulva).
Vaginitis is often caused by an infection, but
it may also be caused by a reaction to vaginal products such as soap, bath
oils, spermicidal jelly, or douches. Vaginitis may cause symptoms such as
vaginal itching, pain, or discharge.
Infections that can cause
vaginitis are common and include:
Yeast infection. A vaginal
yeast infection is caused by a type of yeast called Candida albicans. A yeast infection is also called a candida infection, or
candidiasis. A vaginal yeast infection often causes itching and a white, lumpy
discharge that looks like cottage cheese. It also causes pain with sexual
intercourse. A yeast infection is not a
sexually transmitted infection (STI).
Trichomoniasis. Trichomoniasis is an infection caused
parasite (Trichomonas vaginalis). It is sometimes called trichomonas infection, trichomonal
infection, or simply trich (say "trick"). Trichomoniasis causes a vaginal
discharge that is yellow-green, foamy, and bad-smelling. Pain with sex or
urination may be present. Lower belly pain may also be present. Trichomoniasis
is spread by sexual contact and is an STI.
Bacterial vaginosis. Bacterial vaginosis is a
change in the balance of bacteria that are normally present in the vagina. The
vaginal discharge is thin and milky with a strong fishy odor. Many women have
no symptoms. Bacterial vaginosis is not an STI.
Other sexually transmitted infections (STIs). Infections such as
herpes simplex, and
gonorrhea can also affect the vagina. These infections
are found by doing other tests.
A vaginal sample may be tested by:
Wet mount. A sample of the vaginal discharge is
placed on a glass slide and mixed with a salt solution. The slide is looked at
under a microscope for bacteria, yeast cells, trichomoniasis (trichomonads),
white blood cells that show an infection, or
clue cells that show bacterial vaginosis.
KOH slide. A sample of the vaginal discharge is
placed on a slide and mixed with a solution of potassium hydroxide (KOH). The
KOH kills bacteria and cells from the vagina, leaving only yeast for a yeast
Vaginal pH. The normal vaginal
pH is 3.8 to 4.5. Bacterial vaginosis, trichomoniasis,
atrophic vaginitis often cause a vaginal pH higher
Whiff test. Several drops of a potassium hydroxide
(KOH) solution are added to a sample of the vaginal discharge. A strong fishy
odor from the mix means bacterial vaginosis is present.
Why It Is Done
A vaginal wet mount is done to find the
cause of vaginal itching, burning, rash, odor, or discharge.