Call Us Today! 022-33814248

Bacterial Vaginosis

Bacterial Vaginosis – Risk Factors, Causes, Diagnosis and its Treatment



Bacterial vaginosis is the most common genital disease in women and is caused by excessive bacteria in the vagina. It is also known as vaginal bacteriosis or Gardnerella vaginitis. Although, normal bacterial flora consists of many bacterial and yeast strains which exists in perfect balance; as soon as this balance is disturbed, one or the other strain can grow excessively. Bacterial vaginosis condition usually exists in women between the ages of 14-49 years and about 70% of women around the world are known to have suffered from a bout of bacterial vaginosis at one point in life or another.

Risk Factors

In some cases bacterial vaginosis can remain asymptomatic and even if it is diagnosed and treated, the infection can relapse. Bacterial vaginosis occurs because of imbalance in natural flora of the vagina, which can degrade the normal resistance of body towards diseases. Although bacterial vaginosis itself isn’t a sexually transmitted disease, it does increase the chances of contracting other sexually transmitted diseases in infected women. Bacterial vaginosis infection in pregnant women can also increase the risk of early childbirth, miscarriage and uterine infection.


Bacterial vaginosis is caused by imbalance in the chemical and biological composition of vaginal flora. There are various strains of Lactobacillus bacteria which naturally flourish in the vagina. These bacteria produce hydrogen peroxide which in turn controls the excessive multiplication and symptomatic growth of other microorganisms in the vagina. In bacterial vaginosis, other species of bacteria such as Gardnerella vaginalis, Mycoplasma hominis, Ureaplasma urealyticum and many other strains of Gram negative anaerobic bacteria proliferate extensively. This in turn arrests the growth of Lactobacillus bacteria, allowing the imbalance to persist. The most common reasons for the development of bacterial vaginosis are –

  • Douching: The practice of flushing a body cavity (in this case, vagina) with water for health or hygienic reasons. This process can drastically imbalance the bacterial population of the vagina and increase the risk of contracting bacterial vaginosis.
  • Long term anti-biotic treatment: If due to other illnesses, a woman is undergoing anti-biotic treatment then the anti-biotic effect can also reduce the Lactobacillus population of vagina. As the hydrogen peroxide producing bacteria go down in number, the anaerobic bacteria can increase with the onset of bacterial vaginosis.
  • Pregnancy induced hormonal changes: Hormonal changes can alter the chemical and biological state of vagina, increasing the risk of developing bacterial vaginosis.
  • Menopause: Although this is a rare condition, women can also develop bacterial vaginosis during menopause as a result of hormonal fluctuations and chemical imbalance in the vagina.


The most common symptom of bacterial vaginosis is vaginal discharge which is greyish white in colour and has a distinct fishy smell. This discharge is different from other vaginal infections yet can be misinterpreted as fungal or yeast infection of vagina. Thus various diagnostic measures are available to confirm the presence of bacterial vaginosis –

  • Whiff test: A swab collected from vagina is mounted on the microscopic slide and small amount of potassium hydroxide is added to it. Subsequent release of fishy odour confirms bacterial vaginosis as a positive whiff test.
  • Clue cells on microscopy: Epithelial cells coated with bacteria can be observed in a sodium chloride solution when vaginal discharge is mixed in it. These cells are thus called clue cells as they expose the cause and nature of vaginal infection.
  • pH test of vagina: Normal vaginal acidity level is within the range  of 3.8 – 4.2. Upon the onset of bacterial vaginosis, vaginal acidity level can increase beyond 4.5; which can also be determined with a litmus paper test of the vaginal discharge.
  • BVBLUE: This is a CLIA-waived rapid diagnostic that is considered a much more accurate and efficient test to confirm bacterial vaginosis.
  • Gram stain differential diagnostic is also available for confirmation of bacterial vaginosis infection.

Treatment for Bacterial Vaginosis

Both oral and topical treatment options are available for bacterial vaginosis. Metronidazole and clindamycine can be ingested or applied on vagina (both variants are available). Although earlier a single dose administration was recommended by physicians, it is not very effective. Recurrence of infection is very common and therefore, a 7 day course of metronidazole (500mg, twice a day) is now recommended. Topical medicines are antibiotic in nature and arrest the growth of gram negative bacterial strains. An alternative treatment which is considered highly effective is the use of probiotics. These topic medications or probiotic food supplements result in a surge of Lactobacillus growth in vagina, naturally restoring the chemical and biological balance of vagina. Many physicians recommend probiotic and antibiotic treatment to be administered complementarily.