Clinically reviewed by Dr. Ponlawat Pitsuwan, Physician, Doctor Bangkok. Last reviewed: August 2026
Vaginal discharge colours range from normal clear and white to concerning yellow, green, or grey. Colour alone does not give the full picture. Odour, consistency, and your symptoms together are what matter. If your discharge has changed colour, smells different, or came after unprotected sex, get it checked.
You noticed something different. Maybe the colour changed, the smell is off, or you just feel like something is not right. If you are in Bangkok and far from a doctor you know, that uncertainty can feel worse than it needs to be.
Most changes in vaginal discharge are not serious. But some are. And because several infections cause no symptoms at all, colour alone cannot tell you whether you need treatment. This guide walks through every colour, what it usually means, what warning signs to watch for, and when to get tested.
What Vaginal Discharge Actually Is
Your vagina cleans itself. Discharge is part of that process. It carries old cells and bacteria out and keeps the vaginal lining healthy.
Healthy discharge changes throughout your cycle. When the balance of vaginal bacteria shifts, whether from infection, antibiotics, hormones, or sexual activity, the discharge often changes colour, smell, or texture. A change in your usual pattern is worth paying attention to.
How to Read Discharge: Colour, Consistency, and Odour Together
Colour is one piece. Consistency and odour are just as important. A clinician never looks at colour alone.
Thin and watery with no odour is very different from thin and watery with a strong fishy smell. Thick white with no symptoms is different from thick white with itching and burning. Look at all three together when trying to figure out what your body is telling you.
Clear Discharge
Clear discharge is normal at most points in your cycle. Around ovulation, it becomes stretchy and slippery, a bit like raw egg white. Outside of ovulation, it is usually watery and less obvious. If it is clear and has no unusual smell, no action is needed.
White Discharge
Milky white or creamy discharge is normal, especially in the first half of your cycle. It tends to be thicker in the days before your period.
The one to watch for is thick white discharge with itching, burning, or a cottage cheese texture. That pattern points to a yeast infection. Yeast infections are not sexually transmitted, but they do need treatment. If symptoms keep coming back, a swab test is worth doing to confirm what you are dealing with.
Yellow Discharge
This is where people get most anxious, and it is also where context matters most.
Pale or off-yellow discharge, especially when dried on underwear, is often normal. Discharge oxidises as it dries and can shift colour slightly. If it is pale, odourless, and you feel fine, it is likely nothing.
Bright yellow, yellow-green, or yellow discharge with an odour is a different story. That combination can point to gonorrhoea, chlamydia, or Mycoplasma genitalium, a bacterial infection that is increasingly common and often missed on basic swabs. A frothy yellow-green discharge with irritation raises the possibility of trichomoniasis.
None of these can be distinguished by eye alone. If the discharge is freshly yellow and comes with any smell, discomfort, or pain, get a swab done.
Green Discharge
Green discharge almost always means infection. Gonorrhoea, trichomoniasis, and advanced bacterial infections can all cause it. This is not something to monitor or wait out. A test is needed.
Grey Discharge
Grey discharge is one of the most commonly missed signs. It deserves more attention than most guides give it.
Grey discharge with a fishy odour is the classic sign of bacterial vaginosis, or BV. The smell is often strongest after sex or during your period. BV needs antibiotic treatment. Over-the-counter yeast treatments do not work for BV and can make it worse. A swab will confirm the diagnosis.
Some women with BV notice mainly the odour and very little discharge. If that sounds familiar, do not assume it will resolve on its own.
Brown or Black Discharge
Brown discharge is almost always old blood. Seeing it at the very end of your period, or just before it starts, is normal.
Post-sex brown or pink-brown discharge can come from minor cervical irritation, especially if you have a cervical ectropion, where fragile tissue at the cervical opening bleeds easily on contact. This is common and usually benign, but it needs a clinical check to rule out cervical polyps. Black discharge sounds alarming but is usually the same as brown: older blood that took longer to exit. Persistent dark discharge outside of your period warrants a check.
Pink Discharge
Pink discharge is light bleeding mixed with normal discharge. It is common around ovulation, at the start or end of a period, or as very early pregnancy spotting.
Post-sex pink discharge is worth mentioning to a doctor. In most cases it is cervical ectropion, which is not dangerous but should be confirmed. Repeated post-sex bleeding should not be ignored.
Red Discharge Outside Your Period
Bleeding between periods, or red discharge with pelvic pain, needs prompt assessment. These symptoms can indicate pelvic inflammatory disease, known as PID. PID can develop when an untreated infection, often chlamydia or gonorrhoea, moves into the uterus or fallopian tubes. It can cause long-term fertility problems if not caught early. Pelvic pain combined with abnormal discharge is not something to wait on.
Vaginal Discharge and STIs in Bangkok
STI rates in Thailand have been rising, and Bangkok sees large numbers of tourists and expats. Chlamydia is the most commonly identified bacterial infection in women presenting with abnormal discharge at sexual health clinics here. Gonorrhoea is also prevalent. Both can cause very mild or no symptoms, meaning discharge may look almost normal even when an infection is active.
Many patients who come to Doctor Bangkok for discharge concerns have no idea they have an STI until the swab result comes back. Trichomoniasis, Mycoplasma genitalium, and gonorrhoea all cause discharge that can look similar. Without a test, treatment is guesswork.
If you have had unprotected sex and your discharge has changed at all, testing is the right call. Visit our vaginal discharge and STD testing page to see what each panel covers.
When to See a Doctor in Bangkok
See a doctor the same day if you have green discharge, discharge with pelvic pain or fever, red bleeding outside your period, or symptoms that appeared after unprotected sex.
Book within a few days if you have grey discharge with a fishy odour, thick white discharge with itching that has not cleared up, yellow discharge with any smell, or new post-sex spotting.
Doctor Bangkok is centrally located, BTS accessible, and all consultations are with English-speaking physicians. A full swab panel can be done at the same visit as your consultation. Hotel visits can also be arranged for most consultations. Contact the clinic directly to organise that.
Quick Reference: Vaginal Discharge Colour Chart
| Colour | Likely Cause | Key Symptoms | Action |
|---|---|---|---|
| Clear | Normal discharge or ovulation | Stretchy at ovulation, watery otherwise | No action needed |
| White (milky, no symptoms) | Normal cycle discharge | No itch, no odour | No action needed |
| White (thick, cottage cheese) | Yeast infection | Itching, burning | Antifungal treatment; swab if recurrent |
| Pale yellow (dried) | Oxidised normal discharge | No odour, no symptoms | No action needed |
| Bright yellow or yellow-green | Gonorrhoea, chlamydia, trichomoniasis, Mycoplasma genitalium | Odour, froth, irritation | Get a swab test |
| Green | Bacterial or parasitic infection | Strong odour, irritation | Get tested promptly |
| Grey | Bacterial vaginosis | Fishy odour, worse after sex | Antibiotic treatment; swab to confirm |
| Brown | Old blood, end of period, cervical irritation | Minimal symptoms | Monitor; see doctor if persistent or post-sex |
| Pink | Ovulation spotting, implantation, cervical ectropion | Light spotting, no pain | See doctor if post-sex or recurrent |
| Red (outside period) | Intermenstrual bleeding, PID, cervical polyp | Pelvic pain, irregular bleeding | See a doctor promptly |
Unusual discharge in Bangkok? Doctor Bangkok offers discreet, same-day vaginal swab testing and STI panels with English-speaking physicians. Results are available fast, consultations are private, and the clinic is BTS accessible in central Bangkok. Book online or walk in. Visit doctorbangkok.co.th/std-test-bangkok/ to see what each panel covers.
Frequently Asked Questions
What vaginal discharge colours are a sign of an STI?
Bright yellow, yellow-green, and green discharge can all point to an STI. Trichomoniasis often causes a frothy yellow-green discharge, while gonorrhoea and chlamydia can cause yellow discharge with odour. Many STIs cause no discharge change at all, so testing after unprotected sex matters even when everything looks normal.
Can yellow discharge be normal?
Pale or off-yellow discharge dried on underwear is often normal. Discharge oxidises as it dries and can shift colour slightly. If it is pale, has no odour, and you feel no discomfort, it is usually fine. Bright yellow or yellow-green discharge with a smell warrants a swab test.
I am in Bangkok and noticed unusual discharge. Where should I go?
Doctor Bangkok offers English-speaking doctors, same-day swab testing, and discreet consultations in central Bangkok, accessible by BTS. You can walk in or book in advance. Hotel visits can also be arranged for most consultations. See the full STI testing options at Doctor Bangkok for what is included.
What does grey vaginal discharge mean?
Grey discharge is most commonly caused by bacterial vaginosis. The giveaway is a fishy odour that gets stronger after sex or during your period. It needs antibiotic treatment and will not respond to yeast infection products. A swab confirms the diagnosis before treatment starts.
Should I get tested even if my discharge looks normal?
Yes. Chlamydia, the most common bacterial STI, frequently causes no change in discharge at all. The same is true for early gonorrhoea. If you are sexually active with new or multiple partners, routine screening makes sense regardless of symptoms. Doctor Bangkok offers same-day panels covering the most common infections in a single visit.
What is the difference between bacterial vaginosis and a yeast infection?
Bacterial vaginosis typically causes grey or thin white discharge with a fishy odour and little itching. A yeast infection usually causes thick white cottage-cheese discharge with significant itching and burning, and little to no odour. They are treated differently, which is why a swab matters before starting treatment.
Dr. Ponlawat Pitsuwan
Physician, Doctor Bangkok
a private medical clinic in central Bangkok. He sees expats, residents, and medical tourists for sexual health concerns, vaginal discharge assessment, STI testing, and general medical consultations. His focus is straightforward, evidence-based care delivered in plain language.
Dr. Ponlawat Pitsuwan is a physician at Doctor Bangkok, a private clinic in central Bangkok. He sees expats, residents, and medical tourists for general medicine, wellness consultations, and IV therapy. His focus is straightforward, evidence-based care delivered in plain language.
