Overgrowth of anaerobic bacteria - not a STI

  • Gardnerella vaginalis (most common)
  • Mycoplasma hominis
  • Prevotella species

Can occur along side other infections - candidiasis, chlamydia and gonorrhoea

  • Multiple sexual partners (although it is not sexually transmitted)
  • Excessive vaginal cleaning (douching, use of cleaning products and vaginal washes)
  • Recent antibiotics
  • Smoking
  • Copper coil

Presentation

  • Fishy-smelling watery grey or white vaginal discharge
  • Itching irritation and pain are nottypically associated with BV and suggest an alternative cause
  • Examination not always required if symptoms are typical but a speculum exam can be performed to confirm the discharge and exclude other causes

Investigations

  • Vaginal pH - normal range is 3.5-4.5. BV occurs with a pH above 4.5
  • Vaginal swab for microscopy - BV gives “clue cells” - epithelial cells with bacteria stuck in them

Management

  • Asymptomatic does not require any treatment and may spontaneously resolve
  • **Metronidazole**is the antibiotic choice as anaerobic bacteria targets. Given orally or by vaginal gel. Patients must avoid alcohol while taking
  • Clindamycin is an alternative but not optimal
  • Always assess the risk of pelvic infections with swabs - chlamydia and gonorrhea

Complications

Bacterial vaginosis can increase the risk of catching sexually transmitted infections, including chlamydia,gonorrhoeaand HIV.

It is also associated with several complications in pregnant women:

  • Miscarriage
  • Preterm delivery
  • Premature rupture of membranes
  • Chorioamnionitis
  • Low birth weight
  • Postpartum endometritis