Bacterial vaginosis

What is bacterial vaginosis? And what causes BV?

Bacterial Vaginosis (BV) is a vaginal condition caused by an imbalance in the pH levels in your vagina.

BV is a wider spread condition than many believe, mostly due to it often being misdiagnosed as thrush due to similarities between the two. In fact, women in the UK suffer from BV more than any other vaginal condition, and almost double the amount of women who suffer from thrush.

For the vagina to remain healthy and free from infection, it is important that the many naturally occurring bacteria that live there remain in perfect balance. The bacteria usually present in the largest numbers are those which produce lactic acid, helping to maintain the normal low pH of the vagina and protect against infection.

However, if the numbers of lactic acid bacteria are reduced, pH levels rise, encouraging the growth of other bacteria and resulting in embarrassing odours, abnormal vaginal discharge and discomfort.

These unpleasant symptoms all point to BV. Experts estimate that at least one in three women will develop BV at some point in their life.

What are the symptoms of BV? And do I have it?

There are a number of common symptoms associated with bacterial vaginosis. Things to look out for include:

Bacterial Vaginosis Symptons

Symptoms to look out for include:

  • An unpleasant ‘fishy’ odour, which may be most noticeable after sex
  • Abnormal discharge – usually thin and grey, often heaviest just after a period and after having sex
  • Vaginal discomfort caused by increased discharge/moisture

Due to its symptoms, BV is often mistaken for thrush, which is far less common, but a much better known cause of vaginal discharge. If you think you may have BV or another vaginal condition, check your symptoms with our interactive guide.

However, it’s important to note that 50% of women will have no symptoms whatsoever. So if you are weary of this, speak to one of our knowledgeable advisors or your local GP today.

What causes a pH imbalance?

It’s easy to assume that bacterial vaginosis is caused by poor feminine hygiene, but in fact it could be the opposite.

The vagina is normally quite acidic (pH 3.8 – 4.5), but certain things can cause a reduction in this acidity.

What are the main bacterial vaginosis causes?

What Causes BV

Causes include: a new sexual partner, multiple sexual partners, same sex sexual partners (commonly from use of shared sex toys), the menopause and hormone imbalance.

It is important to remember that BV is not a sexually transmitted infection and any male sexual partners would not need treatment. You do not need to be sexually active to get the condition however. Other causes include:

  • IUDs
  • excessive washing or douching
  • perfumed feminine hygiene products, soaps, gels or bubble baths
  • antibiotics
  • your period

A woman’s age and lifestyle can also have a significant effect on how and why BV develops plus the symptoms that are displayed. Click here to learn more.

How does BV effect different age groups?

Throughout a woman’s life, there are a number of factors that can affect the chances of developing Bacterial Vaginosis, and many things worth knowing should the condition arise.

Late teens/early 20s


Over a third of young women have heavy periods, mostly due to a temporary, usually self-correcting, hormone imbalance. BV often occurs around the time of your period, as menstruation can upset the pH balance of your vagina.

You may notice a change in your normal discharge and an unpleasant odour. If so, avoid using perfumed or intimate health products to mask the smell, as these can exacerbate BV. Instead, try to change your sanitary towels or tampons more regularly.


Even if you’re not sexually active, your doctor may prescribe certain contraceptive methods like the pill or intrauterine devices, such as the coil, to make your periods lighter. However, if you’re prone to BV, intrauterine devices can increase your risk of getting bacterial infections, so make sure you discuss this with your GP.

BV Life Stages

Late 20s/early 30s

Sex toys

Over a third of 25-34 year olds use sex toys – more than any other age group.

But did you know that using toys can upset the pH balance of your vagina? In fact, putting anything foreign in the vagina, including lubricants and even semen, can affect your intimate health. This is because the vagina is naturally acidic and these can reduce this, leading to BV.

If you are prone to BV, use water-based lubricants and latex-free condoms, which can help reduce irritation and use recommended antibacterial wipes especially for sex toys.


If you have untreated BV while pregnant, you run the increased risk of miscarriage or premature labour, so it is important to get this checked out before you conceive.

If you suffer from recurrent BV when pregnant, wear cotton underwear and loose-fitting clothing as often as possible. If your symptoms persist, speak to your doctor about suitable treatments.

BV is not normally considered to be harmful in otherwise healthy, non-pregnant women. However, it can cause significant complications in pregnant women such as:

  • Late miscarriage
  • Preterm birth
  • Low birth weight
  • Premature rupture of membranes (waters breaking early)

You should consult your doctor if you have any symptoms of a vaginal infection during pregnancy.

Late 30s/early 40s

Sex without a condom

Sex without a condom can increase your risk of catching a sexually transmitted infection (STI). Usually, if you are in a monogamous relationship, your risk is greatly reduced. However, it is not just STIs that can affect your personal relationships; BV can too.

Although BV is not an STI, some women notice the symptoms after sex. This is because the vagina is naturally acidic, whereas semen is alkaline, and therefore alters the natural pH of the vagina.

If sex brings on the symptoms of BV, use a condom (preferably latex-free) to reduce the risk.


Hormone imbalances and hysterectomies

The average age at which women enter the menopause is around 51, but some will experience it as early as 45. Hormone imbalances during the menopause are common and can bring on the symptoms of BV, as can vaginal operations and hysterectomies.

Heavy periods

The average period lasts for between four and five days. However, prolonged menstruation lasting seven days or more can reduce the acidity of the vagina, encouraging the growth of unwanted bacteria and leading to BV.

The chance of heavy periods being caused by an underlying condition increases with age – fibroids, endometriosis, pelvic inflammatory disease and polyps of the lining of the womb are more common in older women. If you think your symptoms may indicate a more serious condition you should visit your GP.


Around 40% of women over the age of 45 also say they would wash more often if they noticed an abnormal vaginal discharge or fishy odour. However, this can exacerbate symptoms. If you do notice these symptoms, you should avoid excessive washing and the use of shower gel, antiseptic agents or shampoo in the bath.

What are the implications of BV?

Bacterial Vaginosis (BV) is not dangerous in itself, but it is linked to a number of more serious conditions, both physical and emotional.

BV Implications

Symptoms may resolve without any medical attention, and it is considered unusual for BV to cause complications in otherwise healthy, non-pregnant women.

However, recent research has shown that women with BV are at an increased risk of the following implications:

  • Pelvic inflammatory disease, which can lead to ectopic pregnancy or infertility
  • Endometritis, which can affect fertility
  • Increased risk of contracting STDs, including HIV
  • Post-operative infections in gynaecological procedures
  • Urinary tract infections
  • Second trimester miscarriage
  • Premature birth or low birth weight
  • Pre-eclampsia
  • IVF live birth rate

It isn’t just the physical effects of BV that have an impact on women living with the condition – BV can affect your confidence too. Research shows that 88% of women with BV feel embarrassed and unattractive, with the condition even affecting their relationships.

If you think you may have BV, try Balance Activ BV Gel or a pessary, but if you are in any doubt about your symptoms, please contact your GP.

How to treat and prevent BV

BV Treatment & ProventionTreatment

If you have BV, there’s no need to worry as it’s easily treated.

You can visit your GP who will either prescribe antibiotics, Balance Activ BV Gel or Balance Activ BV Pessaries. Antibiotics are an effective treatment for bacterial vaginosis. However, symptoms of BV may return four to six weeks after the course of treatment, because antibiotics can kill the healthy lactic acid bacteria normally present in the vagina. It can then be difficult to re-establish these healthy bacteria.

Balance Activ BV, however is clinically proven to prevent recurrence of BV. Find out more about it here. You can also buy Balance Activ BV Gel or Pessaries without a prescription from your local pharmacy and all major retailers.

Alternative BV treatment, such as the replacement of lactic acid bacteria, acidifiers, or yogurt can be used, however their effectiveness is limited as they do not stay in the vagina for long enough. Other treatments for BV such as boric acid and hydrogen peroxide have also been used, but there is no robust evidence to suggest that these are particularly effective.

Balance Activ BV is safe to use when pregnant, however, you should see your doctor if you think you have a vaginal infection during pregnancy.

You must also consult your GP if:

  • Your symptoms worsen
  • You experience pain
  • The discomfort does not cease
  • The discharge is blood-stained
  • The discharge occurs during the menopause


There are some simple measures you can take, which could help prevent BV:

  • Avoid excessive washing (or douching) of the vagina: this may alter the normal balance of bacteria, making symptoms more likely to develop
  • Avoid using perfumed intimate products as these can disrupt the natural vaginal balance
  • Use a condom if you notice that sexual intercourse encourages symptoms. Semen is alkaline and can alter the natural pH of the vagina
  • Balance Activ BV, when used regularly, is proven to help prevent BV.