What are the classic symptoms of Bacterial Vaginosis (BV)?

Classic Symptoms of Bacterial Vaginosis

The classic symptoms of bacterial vaginosis (BV) include a homogeneous, white, non-inflammatory vaginal discharge that adheres to the vaginal walls, a fishy odor (especially after intercourse or when mixed with KOH), and minimal irritation, though up to 50% of women with BV may be asymptomatic. 1

Clinical Presentation

• BV is the most prevalent cause of vaginal discharge and malodor in women of reproductive age 1, 2
• The discharge typically has these characteristics:
  • Homogeneous, thin, white or gray in color 1, 3
  • Smoothly coats the vaginal walls 1, 4
  • Non-inflammatory (unlike other vaginal infections) 1
• A distinctive fishy odor is present, which often becomes more noticeable:
  • After sexual intercourse 5
  • When mixed with 10% KOH solution (positive "whiff test") 1
• Unlike other vaginal infections, BV typically does not cause significant:
  • Vulvar irritation or inflammation 2
  • Itching or burning (which are more common with yeast infections) 5
• Importantly, approximately 50% of women who meet clinical criteria for BV have no symptoms at all 1, 6

Diagnostic Criteria

BV is diagnosed using the Amsel criteria, which require at least three of the following four findings:

• Homogeneous, white, non-inflammatory discharge that adheres to the vaginal walls 1
• Presence of "clue cells" (epithelial cells covered with bacteria) on microscopic examination 1, 3
• Vaginal fluid pH greater than 4.5 1
• Fishy odor of vaginal discharge before or after addition of 10% KOH (positive "whiff test") 1

Pathophysiology

• BV results from replacement of the normal H₂O₂-producing Lactobacillus species in the vagina with high concentrations of:
  • Anaerobic bacteria (e.g., Prevotella species, Bacteroides species, Mobiluncus species) 1, 7
  • Gardnerella vaginalis 1, 2
  • Mycoplasma hominis 1, 2
• This alteration in vaginal flora leads to the characteristic symptoms 1, 7

Clinical Significance

• BV is associated with several complications:
  • Increased risk for pelvic inflammatory disease (PID) 2, 8
  • Endometritis and vaginal cuff cellulitis following invasive procedures 1
  • Adverse pregnancy outcomes, including preterm birth 1, 8
  • Increased susceptibility to sexually transmitted infections 2, 6

Common Pitfalls in Diagnosis

• Mistaking BV for other vaginal infections due to symptom overlap 5
• Failing to recognize that up to 50% of women with BV may be asymptomatic 1
• Relying solely on patient-reported symptoms without performing diagnostic tests 9, 3
• Not testing vaginal pH, which is a simple and useful diagnostic tool 1, 9
• Overlooking BV in pregnant women, where it can lead to serious complications 1, 8