Vaginal discharge

What’s normal
It is normal to have some vaginal discharge, because the vagina stays moist as part of its self-cleansing mechanism. The normal moist discharge clears dead cells and bacteria from the vagina. It comes mainly from glands in the cervix (the neck of the womb), and is slightly acidic, which helps to keep infections at bay. The acidity results from lactic acid, formed by friendly bacteria as they break down sugars.

On average, a woman discharges from her vagina about 2 grams of dead cells and about 3 grams of mucus every day, but the amount of normal discharge varies from woman to woman, and with the menstrual cycle. Many women notice that, during the week following a period, there is hardly any discharge, and what there is has a thick consistency. Towards the middle of the cycle (about 2 weeks after the start of a period) the amount increases and it becomes thin, slippery and clear, like uncooked egg white. When this discharge is exposed to the air, it becomes brownish-yellow, so it is normal to find a yellowish stain on your knickers in the middle of the monthly cycle. There may also be a feeling of moistness and stickiness. Normal discharge does not smell, and does not cause any irritation or itching.

Discharge also increases during pregnancy. And during sexual excitement, vaginal discharge becomes very profuse because two glands near the vaginal opening (Bartholin's glands) secrete additional slippery mucus, which acts as a lubricant for intercourse.

What’s not normal

A discharge is likely to be abnormal if:

* it smells fishy
* it is thick and white, like cottage cheese
* it is greenish and smells foul
* there is blood in it (except when you have a period)
* it is itchy
* you have any genital sores or ulcers
* you have abdominal pain or pain on intercourse
* it started soon after you had unprotected sex with someone you suspect could have a sexually transmitted infection.

Causes of abnormal vaginal discharge
Type of discharge Possible causes
Thick and white Normal in some women
Thrush (Candida infection)
Itchy Thrush (Candida infection)
Trichomoniasis
Smelly Bacterial vaginosis
Trichomoniasis
Gonorrhoea
Forgotten tampon

Bacterial vaginosis is a very common cause of vaginal discharge. The discharge smells fishy. You will find more information about bacterial vaginosis in the section on genital infections.

Thrush is caused by the yeast Candida albicans. The main symptom of thrush is itching, but it can cause a thick, whitish discharge. You will find more information about thrush in the section on genital infections.

Forgotten tampons. ‘Lost’ tampons are quite a common cause of discharge. It is easy to forget to remove the last tampon at the end of a period. After a week or two, the tampon begins to fester, and there will be a foul-smelling discharge.

If you have an old tampon in place, remove it as soon as possible. If your discharge continues for more than a couple of days, see your doctor or visit a genitourinary medicine clinic.

Gonorrhoea is one of the most infectious sexually transmitted infections. It is caused by infection with the Gonococcus bacterium. If a woman has unprotected sex with a man who has it, she has a 60-90% chance of catching it. It is serious because if it is not treated, it can spread upwards to the Fallopian tubes. These tubes carry the egg from the ovary to the womb (uterus), so damage to them can cause infertility. About one-fifth of women with gonorrhoea have a foul-smelling, greenish-yellow discharge. About one-fifth have vague symptoms, such as a slight increase in discharge, pain on intercourse or lower abdominal discomfort. About one-fifth have no symptoms at all. (Most men with gonorrhoea notice an obvious discharge from the penis.) You will find more information about gonorrhoea in the section on genital infections.

Trichomoniasis is caused by a tiny amoeba-like (protozoan) organism called Trichomonas vaginalis. It used to be common, but for mysterious reasons is becoming less so; over the last 10 years the number of cases in England and Wales has fallen from 17 000/year to 5000/year. It causes a discharge that is often frothy and yellowish-greenish, but it may be thin and scanty. The discharge is smelly, and the vulva is often itchy and sore. It may also be painful to pass urine. It is caught from a man who has it, but he may be unaware of his condition as most men with trichomoniasis do not have any symptoms. It is not dangerous, though some doctors think it could possibly spread to the Fallopian tubes. You will find more information about trichomoniasis in the section on genital infections. If you think you have this infection, you should visit a genitourinary medicine clinic for treatment and to be checked for other infections.

What to do if you have vaginal discharge

* For any vaginal problem, you must take care to avoid substances that may cause more irritation. These are the same as those that can cause vulval irritation, so look at the list of dos and don’ts for vulval problems.
* During a period, change tampons or sanitary pads frequently (at least two or three times a day), and do not use tampons when you are not having your period.
* Talk to your partner. Ask if he has any discharge from the urethra (the opening at the end of the penis) or any soreness or irritation of the penis. If his answer is ‘yes’, or if there is any reason to think that he might have a sexually transmitted infection, he should go to a genitourinary medicine clinic for a check-up. Do not have sex until the problem has been sorted out.
* If your discharge is thick and white and itchy, it may be thrush, so you could try an anti-thrush cream or tablet from a pharmacist. However, do not persist with an anti-thrush cream from the pharmacist if it does not resolve the problem in a day or two, or if the discharge returns. Look at the information about thrush in the genital infections section, then see your doctor or go to a clinic to get a proper diagnosis.
* The best plan is to see your family doctor or go to a genitourinary medicine clinic for a check-up. The clinic can do on-the-spot-tests for most causes of vaginal discharge, and you can attend without being referred by your family doctor. You should definitely go to a genitourinary medicine clinic if you think that you might have a sexually transmitted infection (for example if you have had unprotected sex with a new partner, or if your partner has discharge or soreness of his penis).


How your doctor or the clinic can help with vaginal discharge
Usually, the doctor will look at the vulva for any signs of thrush, and will then insert a hollow plastic or metal tube (speculum) into the vagina, in order to look at your vagina (rather like having a smear). Samples of the discharge can be taken by wiping with cotton-wool swabs.

A family doctor will usually have to send the swabs to a laboratory, so it may be some days before the result is available. A sexual health clinic can look at the samples under the microscope straight away, and can usually tell you the diagnosis within half an hour, though they are also sent to the main laboratory for confirmation. Do not be surprised if you see the doctor or nurse testing the acidity of the discharge with litmus paper, or mixing some of it with a liquid (potassium hydroxide) on a glass slide and then sniffing it; these are tests for bacterial vaginosis.

Each cause of vaginal discharge has its own proper treatment, which could be a cream or tablet, and it is important to follow the treatment instructions from your doctor or the clinic very carefully. If you are asked to return for another check-up, it is important that you do so, even if the discharge has gone. The clinic may be checking for gonorrhoea, which can damage your Fallopian tubes and infect a future sexual partner without you having any further symptoms.