The vaginal environment is a complex ecosystem and can be easily upset, leading to abnormal vaginal discharge. Two third of cases of abnormal vaginal discharge are due to infections and one third is due to non-infective causes. The commonest infective causes include Bacterial vaginosis, thrush, Trichmonas vaginalis, Chlamydia and Gonorrhoea and herpes.
Abnormal discharge is usually excessive in amount, may be offensive in smell and have a different colour to normal discharge i.e. yellow or green. Often there are other symptoms associated with the discharge, which points towards infection such as itching, redness, pain on passing urine.
This is the commonest cause of abnormal vaginal discharge and is due to overgrowth of mixed bacteria species such as Gardnerella. These replace normal Lactobacillus bacteria that keep the vaginal environment acidic. The discharge is grey/green in colour and tends to have a fishy smell.
Although Bacterial vaginosis is not a sexually transmitted infection, it often occurs in sexually active women.
Diagnosis can be made on culturing the organism from a vaginal swab.
Bacterial vaginosis is treated with the antibiotic metronidazole.
Routine testing and treatment of male partners is not recommended as it does not prevent recurrences
This is infection of the vulval and vagina as a consequence of overgrowth of the yeast, Candida. Thrush can be caused by a number of factors such as vaginal douching, tight fitting clothing, antibiotic treatment and other medications like the contraceptive pill and steroid. It is also seen more commonly in diabetics and can be precipitated by sexual intercourse.
The discharge tends to be cream coloured and is often associated with itching symptoms. Severe thrush can also cause pain on passing urine, redness and swelling to the vulva.
Diagnosis can be made on the history or examination and/or by culturing the yeast by vaginal swab.
Treatment is either with antifungal cream or pessary. Antifungal tablets can be used as a one off dose.
Trichomonas is protozoa and is a sexually transmitted infection. It is most common in women between 18 to 35 years of age.
It usually presents with offensive smelling yellow vaginal discharge. This is associated with vulval itch and sometimes lower abdominal pain and discomfort on passing urine.
Trichomonas can increase the risk of HIV infection and is associated with pelvic inflammatory disease and can lead to complications during pregnancy.
Diagnosis is via culture of the organism from a vaginal swab.
Treatment is with the antibiotic, Metronidazole.
As it is a STI, positive patients should be treated and screened for other STIs, as should their partners.