Discharge (Vaginal)
Symptoms, Causes & Treatment
Understanding vaginal discharge: what is normal, what changes mean, and when to seek assessment and treatment.
What Is Vaginal Discharge?
Vaginal discharge is a fluid produced by glands in the vagina and cervix. It is a normal, healthy part of female physiology. Its purpose is to keep the vaginal tissues moist, provide lubrication, and help prevent infection by maintaining an acidic environment that discourages the growth of harmful bacteria.
Every woman produces vaginal discharge throughout her reproductive life. The amount, colour, and consistency of normal discharge varies between individuals and fluctuates throughout the menstrual cycle, during pregnancy, with sexual arousal, and at different life stages.
Abnormal vaginal discharge -- a change in colour, consistency, smell, or amount that is different from your usual pattern -- is one of the most common reasons women seek medical advice. It can be caused by a range of conditions, from common infections such as bacterial vaginosis (BV) and thrush, to sexually transmitted infections (STIs), and occasionally by other gynaecological conditions.
Understanding what is normal for you, and recognising when something has changed, is the key to knowing when to seek help.
What Does Vaginal Discharge Look Like?
Understanding the difference between normal and abnormal discharge — and between different types of abnormal discharge — helps identify the most likely cause and appropriate action.
Normal discharge varies throughout the cycle: clear and watery around ovulation, thicker and white before periods · Abnormal discharge: yellow/green colour · Grey or strongly fishy-smelling (BV) · Thick white ‘cottage cheese’ with itch (thrush) · Unusual volume increase · Discharge with pelvic pain or bleeding
Yellow, green, or frothy discharge with pelvic pain or fever — possible STI (chlamydia, gonorrhoea, trichomoniasis) or PID · Postcoital bleeding with unusual discharge · Discharge with intermenstrual bleeding — seek same-day assessment
Abnormal discharge accompanied by pelvic pain, fever, or intermenstrual bleeding should be assessed the same day — these may indicate PID which can permanently damage the fallopian tubes if untreated. Unusual discharge after a new sexual partner warrants an STI screen.
What Causes Vaginal Discharge?
Vaginal discharge is a normal and healthy part of the female reproductive system. Understanding what is normal and what indicates a problem helps guide when to seek assessment.
Normal discharge is produced by the vaginal glands and cervix and varies with the menstrual cycle, pregnancy, arousal, and hormonal changes. No treatment is needed for physiological discharge.
Chlamydia, gonorrhoea, and trichomoniasis all cause abnormal discharge. Chlamydia is often asymptomatic; gonorrhoea produces yellow-green pus-like discharge; trichomoniasis causes frothy yellow discharge with odour.
Normal vaginal discharge is clear or white, odourless or mildly scented, and varies throughout the cycle. Discharge is produced continuously by the cervix and vaginal walls as a self-cleaning mechanism.
BV produces thin, grey-white, fishy-smelling discharge. Thrush produces thick, white, cottage-cheese discharge with intense itch. STIs produce yellow-green or frothy discharge often with pelvic symptoms.
BV occurs when Lactobacillus-dominant vaginal flora is displaced by overgrowth of anaerobic bacteria. It is not a sexually transmitted infection but is more common in sexually active women.
Candida albicans overgrowth causes thrush. Triggered by antibiotics, hormonal changes, diabetes, tight clothing, and perfumed products that disrupt the normal acid-alkaline balance.
Key Risk Factors
How Is Abnormal Discharge Investigated?
The colour, consistency, smell, volume, and associated symptoms of discharge guide investigation. An STI screen, high vaginal swab, and pH testing are the key investigations for abnormal discharge. A pregnancy test should be performed if relevant.
How Is Abnormal Discharge Treated?
Treatment depends entirely on the underlying cause. Using the wrong treatment (e.g. thrush cream for BV) will not work and delays appropriate care.
Supportive Measures
Avoid perfumed products in or around the vagina. Do not douche. Wear breathable cotton underwear and change out of damp swimwear promptly. If you have been treated for BV or thrush, complete the full course. Consider probiotics to restore vaginal Lactobacillus after antibiotic use. If you are sexually active with new or multiple partners, use condoms and attend for annual STI screening.
Persistent or Recurrent Abnormal Discharge
Persistent or recurrent abnormal discharge that has not resolved with standard treatment requires further investigation. Consider treatment-resistant STIs (especially gonorrhoea resistance), Mycoplasma genitalium, or underlying conditions such as cervical ectropion or polyps. Specialist referral to a sexual health or gynaecology clinic is appropriate.
When Should You Seek Medical Advice?
Abnormal discharge with fever and severe pelvic pain — possible pelvic inflammatory disease (PID). PID is a gynaecological emergency — seek same-day assessment.
Discharge is accompanied by pelvic pain or fever · Discharge occurred after a new sexual partner and has not been investigated · You have not had an STI screen in over a year and are sexually active · Discharge is yellow, green, or frothy · Treatment has not worked after completing the course.
How to Maintain Healthy Discharge
Keeping vaginal discharge normal and healthy is largely about avoiding disruption to vaginal flora and getting regular STI checks.
Any change in vaginal discharge — particularly new odour, colour change, or discharge with other symptoms — should be assessed by a clinician. STIs may be asymptomatic and require testing.
Attend annual sexual health screens if sexually active. Regular STI testing allows early identification and treatment of co-infections that may worsen vaginal health.
Change out of wet swimwear promptly. Wear breathable cotton underwear. Avoid tight synthetic clothing which creates warm, moist conditions that promote Candida and anaerobe growth.
Avoid condoms lubricated with nonoxynol-9, as it disrupts vaginal flora. Use plain water-based lubricants instead. Barrier protection with male or female condoms reduces BV recurrence risk.
Probiotic capsules containing Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 taken orally or vaginally have evidence for reducing BV recurrence. Take after completing antibiotic courses.
If you have a regular female sexual partner, simultaneous treatment reduces ping-pong reinfection that drives recurrence. Discuss concurrent treatment with your clinician.
Speak to a Clinician About Vaginal Discharge
A licensed clinician at The GP Service can assess your discharge symptoms online, advise on whether investigation or treatment is needed, and prescribe appropriate treatment or arrange an STI screen referral.
Expert clinical advice, when you need it.
Vaginal Discharge FAQs
Most changes in vaginal discharge are caused by benign conditions — BV, thrush, or normal hormonal variation. However, discharge caused by an STI (chlamydia, gonorrhoea, trichomonas) can cause serious complications including pelvic inflammatory disease and infertility if untreated. Any unusual discharge — particularly if accompanied by pelvic pain, intermenstrual bleeding, or occurring after a new partner — should be assessed and tested. Annual STI testing is recommended for all sexually active people under 25 and those with new partners.
Vaginal discharge has a distinctive smell — a mild, slightly acidic scent is entirely normal and reflects the healthy acidic pH of the vagina. A strong fishy smell, particularly after sex, is the hallmark of BV. A yeasty or bread-like smell may suggest thrush. A foul or putrid smell may indicate an STI, foreign body (e.g. forgotten tampon), or pelvic infection. If your discharge smells markedly different from usual, seek clinical assessment.
Yellow discharge is abnormal and should always be investigated. The most common causes are chlamydia, gonorrhoea, or BV. Yellow-green frothy discharge is characteristic of trichomonas. In some cases, yellow discharge may reflect cervicitis or pelvic inflammatory disease. Unlike white discharge (which can be normal or indicate thrush), yellow discharge of any consistency warrants a clinical assessment and STI screen.
Yes. Hormonal changes — particularly oestrogen fluctuations during the menstrual cycle, pregnancy, and menopause — directly affect vaginal discharge. Mid-cycle around ovulation, discharge becomes clear and stretchy (like egg white) as oestrogen peaks. Before a period, it may become thicker and white. During pregnancy, discharge increases significantly due to raised oestrogen and increased cervical gland activity. At menopause, reduced oestrogen causes vaginal dryness and reduced discharge.
Post-coital (after sex) bleeding is not normal and always warrants investigation. Common causes include cervical ectropion (a benign overgrowth of cervical cells onto the outer cervix), cervicitis (cervical inflammation from infection), cervical polyps, or — rarely — cervical cancer. Any woman experiencing regular post-coital bleeding should be seen by a clinician for a speculum examination. Post-coital bleeding alongside unusual discharge should prompt STI screening.
A forgotten or retained tampon causes a foul-smelling, brown or blood-stained vaginal discharge, sometimes with pelvic discomfort. If you suspect a retained tampon or foreign body, do not panic — it can usually be removed by a clinician with a speculum examination. Do not attempt blind digital removal at home as this risks pushing it further. The discharge and smell will resolve rapidly once the foreign body is removed. A short antibiotic course may be prescribed.
Metronidazole (antibiotics) do not cause direct harm to fertility. BV itself, however, particularly in pregnancy, is associated with preterm birth and second-trimester miscarriage. Ascending BV infection can contribute to endometritis and pelvic inflammatory disease, which may affect the fallopian tubes. Treating BV promptly, especially if trying to conceive or pregnant, protects reproductive health. Treatment is safe in the second and third trimesters of pregnancy.
No. BV is not a sexually transmitted infection. You cannot catch BV directly from a sexual partner. However, sexual activity — particularly with new or multiple partners — can alter the vaginal pH and microbiome in ways that predispose to BV. Male partners do not need treatment. Female partners may benefit from simultaneous treatment to prevent recurrence. BV can still occur in women who have never been sexually active.