What The Colour Of Your Period Blood Means, According To Gynaecologists

Experts share what's normal and what isn't when it comes to your menstrual cycle.

Did you know that the colour of your period blood, similar to the smell of your pee, has different meanings and can indicate potential health problems?

You might have noticed that period blood changes colour over the course of your period from a bright to dark red – and that’s normal, according to Dr. Jessica Shepherd, an obstetrician-gynaecologist and medical adviser at O Positiv. However, your period blood may also change colour when there’s something going on down there.

Below you’ll find the colours of your period blood that aren’t a cause for concern, and those that gynaecologists say might warrant a trip to the doctor’s office.

Bright red

For those with a period, a bright-red colour is probably the most recognisable. Whether you noticed a bright-red bloodstain on your bedsheets or through your underwear, it’s typically this colour. This is normal and nothing to worry about in most cases during a regular monthly cycle.

Bright-red period blood is associated with fresh blood that has not been in the uterus or vagina for a long time,” says Dr. Luis Murrain, a doctor and co-founder of Dreams Fertility.

Dr. Alyssa Dweck, a gynaecologist and co-author of The Complete A to Z for your V, adds that a bright-red flow is typical during the active, heavier days of the cycle. If you experience red period blood between cycles, that is something you’ll want to take up with your doctor because it may indicate other internal issues.

Bleeding in between cycles (various shades of red) might signify pre-cancer or cancer, uterine anomalies such as a polyp, vaginal growth or pregnancy, Dweck says.

Dark red, brown or black

If it’s been a while since you’ve last changed your pad or tampon, then you might notice the blood is darker and this is normal.

Dark brown or black typically suggests older blood,” Dweck says. “The process of oxidation occurs over time and turns blood a darker colour, a common finding at the tail end of the cycle.”

The general rule of thumb is the older the blood, the darker the colour.

While black period blood is likely a sign of older blood, it could also be an indicator of a vaginal blockage. These types of blockages are usually accompanied by a fever, smelly discharge and swelling around the vagina.

Light pink

For period blood that is light pink, you might want to take a trip to the doctor to run some tests.

Very light pink, with a watery texture could signify anaemia or low blood count or iron,” Dweck says. “This typically occurs with chronic and excessive flow or in those with iron-poor diets.”

Light-pink colour could also be the result of period blood mixed with cervical fluid, along with significant weight loss.

Grey or green

Unlike shades of red, grey or green period blood may be a red flag. “Grey or greenish hues might signify infection; this colour might be accompanied by an odoyr, itch or irritation,” Dweck says.

Grey period blood might indicate bacterial vaginosis, for which you’ll want to visit your doctor for appropriate diagnosis and treatment.

Shades of red typically are nothing to worry about — even black can be considered normal in some cases.
Carol Yepes via Getty Images
Shades of red typically are nothing to worry about — even black can be considered normal in some cases.

What else to consider

You know your body better than anyone else. If you’ve had a period for a while, then you’re probably familiar with the colours and smells that accompany your cycle.

“Learning your cycle and its consistency, the colour, the smell and any other features of it will help when looking for inconsistencies,” Shepherd says.

While changes in colour are important for acknowledging potential issues, Murrain says to keep an eye on “heavy bleeding, requiring the need to change pads or tampons more frequently than two hours, lightheadedness or dizziness associated with menstrual cycle, excess fatigue and weakness associated with the menstrual cycle.”

Additionally, be on the lookout for “multiple large clots larger than a quarter, severe cramping associated with a menstrual cycle, bleeding lasting longer than eight days, bleeding in between your menstrual cycles and abnormal discharge with your bleeding,” Murrain adds.

If any of these arise, it’s important to schedule an appointment with a doctor or get a gynaecologist referral to rule out any further problems. Booking your smear when it’s due or a GP’s appointment to make sure everything is healthy in relation to your cycle and reproductive health is also critical.

For additional questions about period blood and your cycle, consult with your doctor to keep them updated on your specific issues and observations.