Vaginal infections occur when bacteria, fungi or viruses grow in and around your vagina.
Certain types of bacteria live naturally inside your vagina. They produce acid to help fight off other bacteria, viruses and fungi that don't normally live in your vagina.
Vaginal infections are common. For example, around three-quarters of women will have thrush in their lives.
It's normal and healthy for a woman of childbearing age to have vaginal discharge. The amount and colour of the discharge can change during your menstrual cycle, sexual arousal and pregnancy.
Symptoms of a vaginal infection include:
It's important that you see your GP or visit a sexual health clinic if you have any of these symptoms.
Many factors such as having your period, sex without a condom, vaginal douching, or using soap to clean your genital area can upset the levels of bacteria and fungi in your vagina.
A foreign object, such as a forgotten tampon, can also encourage bacteria to grow and cause an infection. Rarely, it can produce a life-threatening complication known as toxic shock syndrome.
Vaginal infections can also be caused through unprotected sexual intercourse or skin-to-skin contact. These are known as sexually transmitted infections (STIs).
The main types of common vaginal infection are described below.
Bacterial vaginosis (BV)
Bacterial vaginosis (BV) is caused when certain bacteria living naturally inside your vagina grow more than usual (for example, Gardnerella vaginalis). It’s the most common cause of abnormal vaginal discharge in women of childbearing age. The vaginal discharge is usually thin and grey with a fishy smell. Sometimes the fishy odour only occurs after sex, when vaginal secretions are mixed with semen.
Possible triggers of BV include:
BV is not always sexually transmitted, although there may be a link with having a new sexual partner or a high number of sexual partners. If left untreated, BV may increase your risk of:
Around two in 10 women have Candida albicans growing harmlessly in their vagina. A change in your vaginal environment can mean the yeast grows more than usual, causing vaginal thrush (vaginal candidiasis).
Common triggers for thrush include:
Using perfumed soap or feminine hygiene sprays, taking the combined contraceptive pill and wearing tight underwear or clothes have also been linked to causing thrush. However, there is not good evidence that these can cause thrush.
Trichomoniasis is caused by a parasite called Trichomonas vaginalis. This is usually transmitted during unprotected sexual intercourse.
Symptoms of trichomoniasis include an itchy or painful vulva with heavy, sometimes frothy, yellow-green, fishy-smelling vaginal discharge. However, half of women with trichomoniasis don't have any symptoms.
If left untreated, trichomoniasis infection may increase your risk of:
Chlamydia is the most common STI in the UK. It is caused by a bacterium called Chlamydia trachomatis.
Many people have chlamydia without knowing it. Seven in 10 women and half of men with chlamydia don't have any symptoms.
In women, chlamydia infection can spread to your womb (uterus), ovaries and fallopian tubes and cause PID. Up to four women in 10 with untreated chlamydia will get PID. PID can damage the fallopian tubes and can increase the risk of:
Gonorrhoea is caused by a bacterium called Neisseria gonorrhoeae, which is passed on during unprotected sexual intercourse.
Half of women with gonorrhoea don't have any symptoms.
Symptoms of gonorrhoea usually appear within two weeks of infection, and may include:
Genital herpes infection is caused by the herpes simplex virus (HSV) being passed on during sexual contact. Once you’re infected, HSV stays in your body for the rest of your life, although it may not always cause symptoms.
Symptoms of genital herpes include:
Genital warts are the most common sexually transmitted viral infection in the UK, and are especially common in people under 25.
Genital warts are caused by HPV (Human Papilloma Virus), which makes cells grow unusually. You can catch genital warts by having sex and/or genital skin-to-skin contact with someone who has them.
Genital warts appear as small, round lumps on or around your vulva, cervix, vagina or anus. It can take several weeks or months after infection for the warts to appear. However, many people with the virus don't develop warts and you may not know you have the infection.
If you have any symptoms, visit your GP or your local sexual health clinic. Your GP may refer you to a sexual health clinic for specialist treatment.
There are different ways to test for a vaginal infection. You may be asked to provide a sample of urine. A doctor or nurse may look inside your vagina using a speculum (which is also used for smear tests) and take a swab (similar to a small, round cotton bud). The swab picks up a sample of discharge or cells from your vagina. These samples may be tested or examined under a microscope in the clinic, as well as being sent to a laboratory for testing.
Some treatments are available from your pharmacist as well as on prescription from your doctor. Always read the patient information leaflet that comes with your medicine.
Most infections respond to antifungal treatments such as clotrimazole cream or pessaries (a medicine you insert into your vagina), or antifungal tablets such as fluconazole. These are available from your pharmacist without prescription. The infection clears up completely in most women. If you’re pregnant, see your GP before taking any medicines to treat thrush.
If your symptoms don't improve within seven to 14 days or symptoms come back, see your GP. He or she may prescribe a different antifungal medicine. If you suffer from repeated infections, a longer course of treatment might be recommended. Male partners don’t need treatment unless they have a rash or a sore penis.
Antibiotic treatment clears BV infection in most women. Antibiotics are usually given in tablet form although sometimes, especially in pregnancy, your GP will prescribe a gel or cream. Male sexual partners don't need treatment.
If you have trichomoniasis, your GP will usually refer you to a sexual health clinic.
Trichomoniasis can sometimes get better without treatment, but your doctor will prescribe antibiotics to make sure the infection clears. Antibiotics may be prescribed as a course of tablets for five to seven days or as a one-off larger dose. Sexual partners need to be treated too as symptoms are less common in men and they may not know they are infected.
Chlamydia and gonorrhoea
Both Chlamydia and gonorrhoea infections are treated with antibiotics.
Your doctor will give you antibiotics as a one-off injection and tablets for gonorrhoea, or for chlamydia a course of tablets or a one-off dose. Sexual partners need to be treated too as symptoms are less common in men and your partner may not know he is infected.
For gonorrhoea, you will be tested again a couple of weeks after you have finished your treatment to ensure that the infection has gone completely. You may also be offered re-testing after chlamydia treatment.
Treatment depends on where the warts are, what they look like and how many you have. You may be given creams or liquids, cryotherapy (a freezing procedure), surgery or laser treatment.
Some women find that the warts go after one treatment, whereas others need several treatments.
Your GP may prescribe antiviral tablets, which can reduce the severity of the attack but don’t eradicate the infection. This means that some women get further attacks. You need to take them for at least five days.
You may also need to use a local anaesthetic ointment on your vulva to help with the pain.
Chlamydia, gonorrhoea, trichomoniasis, genital warts and herpes are passed on by genital skin-to-skin contact or in bodily fluids during sexual intercourse. A condom provides good protection against many STIs. However, genital warts and herpes may still be passed on by contact with skin that is not covered with a condom.
You can reduce your risk of having BV by:
If you're diagnosed with an STI, it's important to contact your previous partners who may be at risk. This is to prevent them from spreading the infection to others. Sexual health clinics can send anonymous notifications on your behalf if you're willing to provide details.
Reviewed by Jane McQueen, Bupa Health Information Team, April 2014.
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This information was published by Bupa's Health Information Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition. The content is intended only for general information and does not replace the need for personal advice from a qualified health professional. For more details on how we produce our content and its sources, visit the about our health information page.
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