What the Color of Your Period Blood Says About Your Health

What the Color of Your Period Blood Says About Your Health

Period blood is also known as menstrual blood or menses. How it looks will change from day to day during your period, and from one period to the next. It's also different from one person to the next.

What you see on your pad, tampon, or in the toilet bowl is a mixture of both blood and tissue from the lining of your uterus. That's why its color and thickness aren't the same as blood flowing in your veins.

This article explains what period blood looks like and why. It also will help you to know when your blood flow is within a range for what's common, and when there is reason to be more concerned.

menstrual blood color
Verywell / Gary Ferster

What Causes Menstrual Bleeding

Your menstrual cycle is controlled by hormones in your body. These hormones regulate when and if your ovaries produce eggs. They also regulate the thickening of the lining of your uterus, also known as the endometrium.

Your period starts when hormonal changes affect the endometrium. It starts to break down and separate from the wall of your uterus. The excess blood and tissue flow down through your cervix, the opening in your uterus, and out through your vagina.

Recap

Period blood is a mixture of blood and the tissue that lines your uterus. This is why its color and consistency are not the same as the bright red blood that courses through your body. When it passes from the vagina, it may appear different for each person.

What Period Blood Looks Like

Menstrual blood can be described in a number of ways. It's useful to think about not just how much you are bleeding, but the color of the blood and the consistency of the flow as it changes across your cycle.

Bright Red

Bright red blood is more new, in that it has passed from your vagina more quickly and recently. You're most likely to see this bright red color at the start of your period.

You may also see brighter blood at times when you have cramps. That's because cramps occur when the uterus contracts. These contractions lead to heavier blood flow.

Dark Red

Period blood that is a darker red, brown, or black, is slightly older blood. This color suggests a slower flow. For most people, the blood gets darker over the course of their cycle. This is because older blood from the deeper parts of the uterine lining is shed and the bleeding slows.

You may have seen this color if you've ever gotten period blood on your clothing and waited for it to dry—though it's a better idea to soak clothes in cold water to keep the bloodstains from setting.

Pink

Some people may see period blood that is very pink during some points of their menstrual cycle. This is usually at the very beginning or end of their period. It indicates very light bleeding.

Pink period blood is nothing to worry about. It's usually just blood mixed with normal mucus, which makes the color lighter.

Consistency

Your menstrual blood may be thin and watery. It also may be thick and sticky. Thin and watery period blood is usually pinker, while thick and sticky discharge is usually more brown.

These changes in its consistency are common at the end of your cycle. This is because most of the endometrial tissue already has been passed.

Changes in the mixture of thickness of period blood also may mean that there is less buildup in the lining of your uterus. This is common as an older person approaches menopause, or in people whose hormones are affected by stress or too much exercise.

Clots

Period blood also may contain some clots. Clotting is what most people see when they cut a finger and the bleeding stops quickly. Substances in the blood, called clotting factors, work to stop the bleeding.

During your period, there are small blood vessels that are torn as the tissue lining the uterus was separated. Hormonal changes signal the end of your period and the lining will start building back up. Clotting factors also are at work as a part of this cycle.

You may see blood clots during your period. They are not necessarily cause for concern. However, visible clots may be a sign that something else is going on in your body.

Clots that are larger than 1 inch in diameter are a sign that healthcare providers may use when diagnosing menorrhagia, or heavy menstrual bleeding.

Extra Thick

Menstrual blood is a little thicker than normal bleeding because of the tissue it contains. But if you see large lumps, or clots, in your period blood, that may be a sign that you have fibroids.

Fibroids are abnormal growths of the uterine wall. These growths are benign and not a sign of cancer. They can, however, cause pain, discomfort, and heavy bleeding in some people.

Recap

Period blood can change in consistency and color. In some cases, blood clots may pass too. This may suggest fibroids or another condition. Large blood clots can also be a sign of a miscarriage or an ectopic pregnancy, which means you should see a healthcare provider right away.

Heavy Amounts of Blood

Different people have different amounts of period blood. The amounts will also change across the menstrual cycle. It's normal for some people to have periods with very light blood flow. Others may have very heavy blood flow that is common for them.

Yet heavy bleeding can be cause for concern. Talk to your healthcare provider if you are bleeding so much and so quickly that you flood your menstrual products. This is also the case if you need to change them more than once an hour.

Extremely heavy, fast menstrual bleeding may be a sign of an underlying bleeding disorder. This is particularly true if you have any family history of a bleeding disorder or have ever been treated for anemia, which affects your red blood cells and the oxygen they carry.

Normal Period Bleeding

Periods come in a wide range of normal. How wide a range? Healthcare providers consider the following things to all be normal:

  • Having a menstrual cycle that lasts anywhere from 24-38 days
  • Having a cycle length that varies as much as 20 days over the course of the year
  • Bleeding for anywhere from four and a half to eight days at a time
  • Losing anywhere from 5 to 80 milliliters (ml) of blood over the course of your period

There's also the question of what's normal for you. Menstrual blood may be thick, thin, pink, or even black. Some people can use only one or two pads or menstrual cups over the course of a day. Others need to change them every couple of hours. Some people have no cramps; others always need a heating pad or pain medicine.

You'll know what's normal for you if you pay attention to what your period blood looks like and what your menstrual cycle feels like. Tracking your period helps you to know if something has changed. It may lead you to seek care based on how your period changes.

Recap

It's important to know what's normal for you. Changes in your period may be a sign of other health issues. For example, you may always experience heavy periods. About 20% of people do. But in others, they may be linked to a bleeding disorder or other medical condition.

Abnormal Uterine Bleeding

Uterine bleeding is not uncommon. Up to 25% of reproductive-age people around the world will experience some type of abnormal uterine bleeding. This bleeding takes on a variety of forms, including periods that:

  • Are too close together or far apart
  • Are much heavier than would be otherwise expected
  • Last for longer or shorter than what's considered to be a normal range

Treating the underlying cause of abnormal uterine bleeding can make a big difference in the lives of those who experience it. For some people, it's the difference between being successful at work or school, and not being able to function.

Changes in your menstrual bleeding can be a symptom of another health issue, such as polycystic ovary syndrome (PCOS). Not all of these conditions are serious or need medical attention. However, signs that you should see a healthcare provider about your period include:

  • Not bleeding for more than three months, when you know you're not pregnant
  • A change from regular to irregular periods (just having a lifetime of irregular periods isn't a concern)
  • Bleeding for more than seven days at a time or between periods
  • Bleeding so heavily that you soak through pads or tampons in only an hour or two
  • Severe pain during your period

If you get a fever and feel unwell after using a tampon, it could be a sign of toxic shock syndrome. This is a rare but potentially fatal condition that requires immediate medical attention.

Summary

Period blood is a mixture of blood and the tissue that lines your uterus. This is why its color and consistency are not the same as the bright red blood that courses through your body.

When it passes from the vagina, it may appear different for each person. The color may be pink, red, brown, or black, all during the same period. It can be thin or thicker. Blood clots that pass during your period may seem normal, or they may be a sign of another health issue.

It's important to know what's normal for you. Talk with your healthcare provider if you have concerns about changes in your period.

Frequently Asked Questions

  • Can Birth Control Be Used to Control Heavy Periods?

    Maybe. It will depend on what's causing your heavy bleeding. A healthcare provider may include birth control pills in your treatment because they reduce the amount of period blood flow.

  • Why Do I Have Brown Discharge Near My Period Time?

    Usually, it's just the body removing old blood cells and cleaning the vagina. But this can be a sign of an infection, PCOS, or even cervical cancer. Talk to your healthcare provider if you have concerns about a brown vaginal discharge.

  • What Is the Color of Spotting Between Periods?

    The blood you see when spotting happens between your regular periods is usually pink, red, or brown. This is often the case for people who approach menopause, as their periods may become more irregular. It also may be a sign of cervical cancer and is worth discussing with a healthcare provider.

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9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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