Vulvovaginitis and Vagninosis

last authored: July 2010, Kim Colangelo
last reviewed:




A change in vaginal discharge is a frequent presenting complaint. While many cases represent normal changes, numerous infections and other causes may be responsible for discharge. As such, thorough clincial assessment and investigation are required.


Vaginosis is different from vulvovaginitis in that there is no inflammatory reaction, however there is overlap in symptoms between the two conditions. 


This topic does not discuss the sexually transmitted infections of Chlamydia and gonorrhea, which are covered in more detail in their own topics.


The Case of Ms. Lyons

A 30yo female presents to her family doctor's office with a 3 day history of a white vaginal discharge. Her main concern is that the discharge smells unpleasant. There is no pruritis, rash, or dysuria. She is otherwise healthy. Gynecological history reveals a past chlamydial infection for which she was treated. 

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Causes and Risk Factors

Physiologic discharge can increase during states of increased estrogen, including pregnancy, oral contraceptive pill use, polycystic ovarian syndrome and premenarche.

The three most common causes of vulvovaginitis are bacterial vaginosis, candidiasis, and trichomoniasis.

The main organisms of bacterial vaginosis (BV) include:

  • Gardnerella vaginalis
  • Mycoplasma hominis
  • Prevotella 
  • Mobiuncus 
  • Bacteroides 

The main risk factors for BV include:

  • sexual activity 
  • douching
  • cigarette smoking

There are three possible species for candidiasis:


Candidiasis risk factors:

  • immunosuppressed host (HIV, diabetes, steroid use, etc)
  • recent antibiotic use
  • pregnancy and other increased estrogen states
  • diaper use or an otherwise prolonged moist environment

Trichomoniasis is caused by Trichomonas vaginalis, which is a flagellated protozoan parasite.


Trichomonas is considered a sexually transmitted infection thus it can be passed between partners.


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clue cells

"Clue cells" suggesting bacterial vaginosis
used with permission, Per Grinsted

Bacterial vaginosis

Hydrogen peroxide producing lactobacilli are normally the predominant organism in the vaginal flora. When these decline, the pH rises (become more alkaline) and anaerobes proliferate. The anaerobes produce enzymes that break down substances into amines that have a foul smell; this, combined with the normal cells of the vagina sloughing off more during bacterial vaginosis, results in the discharge that is characteristic.


If Gardnerella vaginalis is the causative organism it can cling to the epithelial cells sloughing off and create the "clue cells" that are part of the diagnostic criteria.






Candidiasis is a fungal infection. The source may be the perianal area that gains access to the vagina or it may normally be present in the woman and because of altered host factors (such as douching) become symptomatic.



Trichomonas is considered a sexually transmitted infection. Trichomonas has adherence factors that allow it to adhere to the cervicovaginal epithelium and passed between partners.

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Signs and Symptoms

  • history
  • physical exam


History of present illness

  • onset
  • duration
  • previous episodes
  • smell, quantity, thickness, texture
  • itch, pain
  • fever, chills
  • associated with intercourse, menstruation, diet, STI?

Obstetric/gyne history

  • menarche
  • menstruation - regularity, cycle length
  • sexual history
  • sexually transmitted infections

Past medical history


Social history

  • cigarettes
  • alcohol
  • drugs

Physical exam

Abdominal exam:

  • tenderness
  • peritoneal signs

Pelvic exam:

  • discharge
  • lesions, trauma, rashes
  • cervical motion tenderness
  • swabs should be taken


Normal (physiologic) discharge is clear or white and odourless.


 All three infectious causes may be asymptomatic but seen on cultures.


Bacterial vaginosis




grey, thin, watery, foul smelling, copious

white, "cottage-cheese"

yellow-green, foul smelling, copious

Other symptoms

discharge is typically the only symptom

pruritis, dysuria, dyspareunia

pruritis, dysuria, dyspareunia, burning
tender vulva

Physical Exam

copious discharge with no inflammatory reaction

satellite vulvar erythema

swollen, inflamed vulva

strawberry cervix

diffuse vulvar erythema

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Lab Investigations

Normal vaginal discharge, if smeared on a slide, will show epithelial cells (that slough off on a continuous basis) and lactobacilli that are part of the normal vaginal flora. The normal vaginal pH is 3.8-4.2.


Bacterial Vaginosis is diagnosed when at least 3 of the following 4 are present (Amsel criteria):

A vaginal culture is not necessary for diagnosing BV or candidiasis; clinical signs and symptoms alone are sufficient.  If a swab is taken for the wet mount or pH it should be taken from high in the vaginal canal to avoid contamination with organisms of the skin. The swab can then be applied to a wet mount for the whiff amine test or to look for clue cells, or to litmus paper to check the pH.


Bacterial Vaginosis




fishy odour produced

cells remain intact but no odour is produced

can be odour producing


greatly increased



wet mount


clue cells (epithelial cells covered with bacteria)

budding yeast and hyphae

oscillating protozoan

numerous WBC's and inflammatory cells

gram stain


switch from gram positive rods to gram negative rods or curved bacteria

gram positive yeast with buds

large, gram negative protozoan

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Differential Diagnosis

The differential includes:

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Bacterial Vaginosis resolves spontaneously in many women so treatment is indicated for symptomatic relief, in pregnant women, and in women about to undergo pelvic surgery.

Some treatment options include:

Oral probiotics are currently being investigated as a supplement to antimicrobial therapy, as treatment of BV with antimicrobial therapy may lead to Candida infections.

A male partner does not need to be treated, a female partner should be informed of the infection.


Candidiasis is often treated with antifungals, such as fluconazole A single dose of oral treatment is often preferred for convenience, however suppositories and creams are available. The duration of treatment is lengthened in complicated patients (immunosuppressed, pregnancy, recurrent episodes). Acidophilus yogurt is being investigated to treat candidiasis.


Trichomoniasis should be treated with the antibiotic metronidazole. A single dose of oral treatment is often sufficient. As Trichomonas is a sexually transmitted infection, partners should be treated as well.

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Consequences and Course

BV and trichomoniasis are associated with a higher risk of sexually transmitted infections such as HIV, HSV, gonorrhea, and chlamydia. They are also associated with a higher risk of preterm birth and other obstetric complications in affected pregnant women and postoperative vaginal cellulitis in women undergoing pelvic surgery. BV has a high recurrence rate, maintenance antimicrobial therapy has been investigated. The use of condoms or abstinence has been associated with lower recurrence rates.

Vaginal candidiasis is not associated with adverse pregnancy outcomes.

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Resources and References

Society of Obstetricians and Gynecologist of Canada. Clinical practice guidelines. Screening and management of Bacterial Vaginosis in pregnancy. 2008.

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Topic Development

authors: Kim Colangelo, 2010


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