What does the colour of a discharge stain mean?
Which colours of discharge on underwear are normal, which need attention, and how discharge naturally changes across the menstrual cycle.
Stains noticed on underwear often cause worry, but not every change of colour means illness. Even healthy discharge can change colour once it meets the air and dries. Below is which colours are normal, which need attention, and how discharge changes across the cycle.
Which colours are normal
Normal discharge from the vaginal wall is clear, white or slightly cream-coloured. When it dries on underwear and meets the oxygen in the air — oxidises — it can turn slightly yellowish or a deep ivory. Faintly yellowish stains without odour or itching almost always come from this normal drying process and are not a sign of infection.
Which colours need attention
- Dark yellow or yellow-green with an unpleasant odour: particularly together with a frothy consistency, this can point to an infection.
- Uniform grey-white with a fishy odour: may be linked to a disturbance in the natural bacterial balance (bacterial vaginosis).
- White, textured, curd-like or chalky in appearance: usually a typical sign of thrush, and may be accompanied by itching and burning.
- Pink, red or brown: indicates a small amount of blood mixed into the discharge. Before or after a period, or around ovulation, this is generally normal; but if it appears continuously outside a period, or recurs after sex, it needs assessment.
How discharge changes across the cycle
Its consistency and quantity change naturally with the hormones:
- After a period: oestrogen is low, so there is little discharge and it leaves almost no trace.
- Before ovulation: as oestrogen rises, discharge increases and becomes creamy.
- Around ovulation: it becomes clear, slippery and stretchy, leaving noticeable wet marks on underwear.
- After ovulation: under the influence of progesterone it thickens again and takes on an opaque white appearance.
Frequently asked questions
Does every stain mean an infection?
No. Faintly yellowish stains without odour or itching usually come from the drying process and are normal.
When should I see a doctor?
If the change of colour is accompanied by an unpleasant odour, itching, burning or pain in the groin, or if there is recurring brown or pink spotting outside a period.
See also vaginal discharge.