Why is my period blood brown?
Brown period blood is usually older blood. When blood leaves the uterus slowly, it has time to oxidize, which turns it from red to brown. That's why it's common at the very start and end of a period, and on light days. It's usually normal. Brown bleeding with a bad smell, pain, fever or outside your period is worth checking.
Why period blood turns brown
Fresh blood is bright red. As it sits in the uterus or vagina, it reacts with oxygen and darkens to dark red, then brown. On heavy days blood flows quickly and stays red. On light days, at the start of your period and as it tapers off, blood moves slowly and has more time to change color.
When brown period blood is normal
| When you see it | Usually means |
|---|---|
| The first day, before flow picks up | Leftover blood from your last period or slow early flow |
| The last day or two | Flow slowing down; older blood clearing out |
| Light periods all the way through | Slow flow, common on hormonal birth control or in perimenopause |
| A day or two before your period | Premenstrual spotting, often normal. See spotting before period |
| Postpartum weeks | Normal postpartum bleeding (lochia) turns brown as it eases |
If your period starts with a day of brown spotting, count your cycle from the first day of real red flow, not the brown day.
When brown blood is worth checking
- Bleeding between periods or after sex, especially if it keeps happening.
- A strong, unpleasant smell, itching, or unusual discharge, which can mean an infection.
- Pain or fever with brown discharge.
- A late period with only brown spotting, if you could be pregnant: take a test. Early pregnancy bleeding can be brown.
- Brown bleeding after menopause, which always needs checking.
- Something left in the vagina, like a forgotten tampon, which causes brown discharge and a strong smell.
For discharge outside your period, see brown discharge. For the full range of colors, from pink to black, see period blood colors and black period blood.
Brown blood and your mood
Brown spotting a day or two before your period often lines up with the end of the luteal phase, when PMS is usually strongest. Many people find the first day of real flow brings relief as hormones reset. Logging both helps you see your own timing.
See a doctor if you bleed between periods or after sex, have brown discharge with a bad smell, pain or fever, bleed after menopause, or could be pregnant and have bleeding with pain. Get urgent help for heavy bleeding with dizziness or one-sided pelvic pain in pregnancy.
Frequently asked questions
Is brown period blood a sign of pregnancy?
Not usually. Brown blood is common at the start and end of normal periods. But if your period is late and you see only brown spotting, take a pregnancy test.
Why is my whole period brown?
A light, slow flow can stay brown throughout, which is common on hormonal contraception or in perimenopause. If it's new and persistent, mention it to a doctor.
Is brown blood at the start of my period normal?
Yes. It's often old blood from the uterus coming out before the flow picks up.
Is brown period blood a sign of infection?
Only if it comes with a bad smell, itching, pain or fever. On its own, brown blood is usually just older blood.
Sources
This page is for information only and isn鈥檛 medical advice. If something worries you, please talk to a doctor.
Keep reading
What color should period blood be? A simple color guidePeriod blood color guide: bright red, dark red, brown, black, pink, orange and gray, what each usually means, and which colors are worth a doctor's check.
Brown discharge: what it usually means and when to checkBrown discharge is usually old blood. What it means before, after or instead of your period, in early pregnancy and perimenopause, and when to see a doctor.Why is my period blood black?Black period blood is usually old blood that took longer to leave the uterus. When it's normal, what dark blood means, and the signs worth a doctor's visit.Spotting before your period: what's normal and why it happensSpotting before period starts is common. Why light pink or brown spotting shows up in the days before your period, what's normal, and the signs to check.
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