Treating and Preventing Bacterial Vaginosis

Authored by Dr Mary Lowth, Reviewed by Dr Louise Newson on | Certified by The Information Standard

Bacterial vaginosis (BV) often causes no symptoms, or the symptoms are mild. Also, there is a good chance that BV will gradually clear without treatment.

Bacterial vaginosis (BV) often causes no symptoms, or the symptoms are mild. Also, there is a good chance that BV will gradually clear without treatment. There are various different treatments for bacterial vaginosis (BV). There are also some things which you should avoid doing, which may help the problem to resolve itself.

These include avoiding the use of douches, vaginal deodorants, bath additives and harsh soaps. Refraining from intercourse for a couple of weeks, or using a condom and a water-based lubricant, can be helpful.

The body is often very good at getting back its own balance. The disruption in the balance of vaginal germs (bacteria) that causes BV may correct naturally, with time. So, if you have no symptoms or only mild symptoms, you may not need any treatment, particularly if you take some of the general healthy steps above?

You normally need treatment for BV if it is causing symptoms, or if the characteristic smell is noticeable to you. If you are pregnant, trying to become pregnant, or about to have a gynaecological procedure then you may be advised to get treatment for BV.

Pregnancy
If you are pregnant and you are found to have BV then you will usually be offered antibiotic treatment with oral metronidazole (see below).

If you are trying to conceive and you think you may have BV, it is a good idea to try to eradicate the BV through natural methods or treatment prior to conceiving. If you have symptoms then you should discuss having antibiotic treatment with your doctor.

Termination of pregnancy
If you are found to have BV and are undergoing a termination of pregnancy, treatment with antibiotics may be advised even if you do not have any symptoms. This is because there is otherwise a risk of BV causing infection of the womb (uterus) or pelvis after the procedure. This could lead to later fertility problems.

Gynaecological procedures
Antibiotics are not usually recommended for women with BV (and no symptoms) who are about to undergo 'minor' gynaecological procedures such as an endometrial biopsy - a biopsy of the lining of the womb. In fact women having these procedures are in any case not usually tested for BV, so they would not know they had it.

Women having vaginal hysterectomy are given antibiotics prior to the procedure, even if they don't have BV, in order to lower the risk of postoperative infection. These antibiotics will also wipe out any BV-causing bacteria.

There are a variety of possible treatments for BV.

Antibiotics for bacterial vaginosis

Oral antibiotics are the first-choice treatment in pregnant women with BV.

Metronidazole tablets
A full course of metronidazole tablets is the common treatment. Metronidazole is an antibiotic. This clears BV in most cases. It is important to read the leaflet that comes with these tablets for the full list of possible side-effects and cautions. The main points to note about metronidazole include:

  • The usual dose is 400-500 mg twice a day for 5-7 days. A single dose of 2 grams of metronidazole is an alternative, although this may be less effective and may cause more side-effects. (Note: this single dose is not recommended if you are pregnant.) It is important to finish the course you have been prescribed, and not to miss any tablets.
  • Some people feel sick or may be sick (vomit) when they take metronidazole. This is less likely to occur if you take the tablets straight after food. A metallic taste is also a common side-effect.
  • Do not drink any alcohol while taking metronidazole, nor for 48 hours after stopping treatment. The interaction of metronidazole with alcohol can cause severe sickness and vomiting, and may also cause flushing and an increased pulse rate.
  • Metronidazole can get into breast milk in small amounts but will not harm your baby, although it may make the milk taste different. The manufacturer recommends that if you are breastfeeding you should take the 5- to 7-day lower dose course of metronidazole rather than the single large dose.

Alternative antibiotic treatments
Tinidazole tablets may be offered if you know you are intolerant of metronidazole. Tinidazole is a similar antibiotic and you need to take 2 g once a day for two days, or 1 g once a day for five days. It has the same interaction with alcohol that is seen with metronidazole, meaning that alcohol should not be consumed whilst you are taking it, nor for 48 hours afterwards. Tinidazole is not recommended in pregnancy.

Metronidazole vaginal gel or clindamycin vaginal cream placed inside the vagina can be used if you prefer this type of treatment, or if you experience unpleasant side-effects with metronidazole tablets. These treatments are believed to be almost as effective as antibiotics by mouth.

Note: as with metronidazole tablets, you should avoid alcohol while using metronidazole gel and for at least 48 hours after stopping treatment, although the tendency of the gels to make you feel sick are not as noticeable as for the tablets.

Vaginal creams and gels can weaken latex condoms and diaphragms. Therefore, during treatment and for five days after treatment with clindamycin vaginal cream, do not rely on condoms or diaphragms to protect against pregnancy and sexually transmitted infections (STIs).

Other antibiotic tablets taken by mouth are also sometimes used to treat BV. These are clindamycin tablets or tinidazole tablets.

Some women with BV say that things settle more quickly and symptoms are eased by applying a thin coat of plain, live yogurt to the outside of the vagina daily, and by applying a small amount of plain live yoghurt on a tampon for internal use before bed.

The evidence that live yoghurt is helpful in treating or preventing BV is mixed, with some trials saying that it is helpful and some saying that it is not helpful. Overall specialists feel that there is not enough evidence in its favour to suggest it over other treatments.

Treatment with acetic acid gels aims to keep the vaginal pH at less than 4.5, to encourage lactobacilli to grow, and to discourage anaerobic bacteria from growing. Some studies have suggested that long-term use of vaginal acidifiers of this type reduces recurrences of BV. However, other studies suggest that this treatment, whilst harmless, is not effective.

Lactobacillus suppositories and oral tablets are sold in some health food shops, for use in BV.

Orally consumed probiotics are believed to reach the vagina via the bowel. There is some evidence that this can be helpful in treatment and in prevention of BV. These studies suggest treatment needs to continue for at least two months. Other studies don't show a clear benefit. Overall, specialists feel that there is not enough evidence in its favour to suggest it over other treatments.

Intravaginal lactobacillus treatment seems as though it ought to be an obvious solution - why not put the right bacteria where they are meant to go? However, results of studies on vaginal treatments with lactobacilli are also mixed, with some studies suggesting this treatment is effective and others not.

There is no evidence that treating a male sexual partner prevents his female sexual partner from developing BV. One small trial looked at whether using a sterilising alcohol gel on the penis protected their partners against BV - but the gel appeared to make BV more, rather than less, common in the women.

If you have a female partner then it does appear that treating her for BV at the same time as you - even if she doesn't have symptoms - will prevent recurrence (in either of you).

Women who are not pregnant

After treatment, you do not need any further tests to ensure that BV has cleared (a test of cure) provided that your symptoms have gone.

Women who are pregnant

If you are pregnant, it is suggested that you do have a test one month after treatment to ensure that BV is no longer present. A sample (a swab) of the discharge in your vagina is taken. This is tested to check you no longer have BV.

If you have persistent BV (ie it does not settle down with the first treatment you try) then your doctor may want to take further vaginal swabs to check whether there is another cause of the discharge. They will usually suggest that you use the seven-day course of metronidazole if you have not had this before.

Another treatment which may be tried is using metronidazole gel twice a week for up to six months.

If you have a persistent BV infection which does not respond to treatment, and you have an intrauterine contraceptive device (IUCD) then your doctor may advise removing the device until things settle down, as there is some evidence that IUCDs can contribute to persistent BV.

If you have persistent BV and a same-sex partner then treating both of you at the same time is likely to be helpful in preventing persistence and recurrence - even if your partner does not have symptoms.

Most episodes of bacterial vaginosis (BV) occur for no apparent reason and they cannot be prevented. The following are thought to help prevent some episodes of bacterial vaginosis (BV). The logic behind these tips is to try not to upset the normal balance of germs (bacteria) in the vagina:

  • Do not push water into your vagina to clean it (douching). The vagina needs no specific cleaning.
  • Do not add bath oils, antiseptics, scented soaps, perfumed bubble bath, shampoos, etc, to bath water.
  • Do not use strong detergents to wash your underwear.
  • Do not wash around your vagina and vulva too often. Once a day is usually enough, using gentle soaps and water.
  • Don't use perfumed 'intimate hygiene' products.
  • Using a condom and/or a water-based lubricant during intercourse may help protect you.
  • Avoid using sex toys inside the vagina.
  • Avoid thongs and tight nylon tights.
  • Have showers rather than baths.
  • Lighter periods seem to make BV less likely to return, so if you have heavy periods and were considering seeking treatment, this might be another reason to do so.

BV often recurs, usually within a few months of treatment - although if any of the behaviours which can trigger it (such as using douches) apply to you then it may be less likely to recur if you avoid these things.

BV often returns after it has been treated. No good way has been found yet of preventing this from happening.

If you keep getting BV symptoms, your doctor will do some tests to be absolutely sure you have got BV and not any other infection. If it turns out to be definitely BV, a different antibiotic to the one you have taken previously may be tried. Occasionally regular preventative use of an antibiotic vaginal gel may be advised.

If you are using an intrauterine contraceptive device (IUCD) for contraception, it may be advised that you consider having this removed.

If your symptoms come back and you did not have a test using a sample (a swab) of your vaginal discharge taken initially, your doctor or nurse may suggest that they take swab tests now. This is to confirm that it is BV causing your symptoms.

BV may return if you did not complete your course of antibiotics. However, even if you have completed a full course of antibiotics, BV returns within three months in many women. If it does come back, a repeat course of antibiotics will usually be successful. A small number of women have repeated episodes of BV and need repeated courses of antibiotics.

If you have a copper coil for contraception - an IUCD - and have recurrent BV, your doctor or nurse may suggest that they remove your IUCD to see if this helps to improve your symptoms. You will need to consider alternative contraception measures.

If you have a same-sex partner then, even if she has no symptoms, treating both of you at the same time may reduce recurrence.

You should also take particular notice of the advice not to use douches, bath additives and vaginal deodorants. Long-term use of metronidazole gel is sometimes advised. Specialist guidelines in the USA recommend using twice-weekly for up to six months. UK specialist guidelines are less certain on the frequency and duration of preventative treatment, and your doctor may want to talk with a specialist for advice on this.

Further reading and references

Can men get thrush?
What your vaginal odour could mean

Thought I had UTI. Took two sets of antibiotics from urgent care. Didn't work and ended up in ER. Thought it was BV since urine kept coming back clear. Gave me four amoxicillin, shot of rocephrin...

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