Brown period blood is usually just older blood. The longer blood takes to leave your uterus, the more time it has to react with oxygen and darken. That’s why you’re most likely to see it at the very start or end of your period, when flow is slow.
Common reasons for brown blood
- The start or end of your period. This is the most common reason, as flow is at its slowest.
- Implantation bleeding. Light brown or pink spotting can appear about 10 to 14 days after ovulation in early pregnancy.
- Perimenopause. Cycles and flow can change in the years before menopause.
- PCOS, now also called PMOS. Irregular periods may include older, darker blood.
- After giving birth. Bleeding after birth often turns brown as it eases.
- Early pregnancy loss. Brown bleeding can also happen with a missed miscarriage, so bleeding in pregnancy should always be checked.
What other colours mean
| Colour | What it usually means |
|---|---|
| Bright red | Fresh blood with steady flow, usually on heavier days |
| Dark red | Blood that has pooled, such as after lying down |
| Brown | Older blood, usually at the start or end |
| Black | Very old blood, usually on low-flow days |
| Pink | Blood diluted by cervical fluid, usually on light days |
| Orange | Blood mixed with cervical fluid, sometimes linked to infection |
| Grey | Not a typical period colour, so please get it checked |
Want to log what you’re seeing? The flow colour photo check reads a colour on your own device, and doesn’t upload or store the photo.
Three questions that narrow it down
- When did it happen? Brown blood in the first or last days of a period is usually just slow flow. Periods are usually red when they’re heaviest, and pink or brown on lighter days. Brown bleeding between periods is different, and worth checking.
- Could you be pregnant? If so, take a test once your period is late, and tell a clinician about any bleeding during pregnancy.
- Do you have other symptoms? Pain, fever, itching, unusual discharge or a bad smell can point to something that needs treating.
What about clots?
Clots usually form as the uterus sheds its lining, and are more likely when bleeding is heavier. Clots larger than about 2.5cm are worth mentioning to a clinician, because heavy bleeding can lead to anaemia.
When it’s about more than colour
Colour on its own rarely tells you much. It’s more useful to look at your wider pattern. Speak to a clinician if your cycles are often shorter than 24 days or longer than 38, if they change a lot from month to month, or if you’ve had no period for 3 months or longer.
Logging colours in the period tracker over a few cycles shows what’s typical for you. If your period seems late as well, the late period checker can help you work out the next step.
When to get it checked
See a clinician if brown bleeding:
- Happens between periods, or after menopause
- Happens during pregnancy
- Comes with severe pain, fever, itching, unusual discharge or a bad smell
If your discharge is black or smells bad and you may have a forgotten tampon, cup or condom, get seen promptly.
Get urgent help if you could be pregnant and have sudden, intense tummy pain, or feel very dizzy or faint. Call emergency services, as these can be signs of a ruptured ectopic pregnancy.