Why is My Period Blood Black?

For most women, after the first few cycles, periods start to feel like a pretty routine part of life. So when your period decides to throw you a curveball — like black blood instead of red — it’s normal to feel a little bit of panic.

The good news? You’re not the first woman to have black period blood. Periods are great indicators of your overall reproductive health, and black blood in particular may signal several different things.

What does black period blood mean? 

Did you know that period blood comes in a variety of colors? These colors range from bright red to black, and can even sometimes be orange or gray. The color of your period blood is an important indicator of your health. Anything in the red to brown/dark black range is generally considered to be “normal” or “healthy.”

The reason the hue varies so much is because blood changes color as it is exposed to oxygen. Blood that lingers inside of the uterus or takes more time to be expelled is exposed to oxygen longer than fresh period blood, which causes it to become oxidized, resulting in a darker color. So what does black period blood mean? Just that it’s pretty old. Typically, the darker the blood, the older it is.

What causes black period discharge?

So if you’re thinking, “why is my period blood black?”, the answer could actually be a few different things. Sometimes blood just takes a bit longer to leave the uterus at the start or end of your cycle. Having black period blood at the beginning of a period or even towards the end is completely normal.

Occasionally, black menstruation blood can also be a sign of vaginal blockage, cervical cancer, or that you have contracted an STI. In these cases, the black period blood will likely also by accompanied by other symptoms like an unpleasant odor or foul-smelling discharge, burning while urinating, pain during sex, vaginal itching, fever, trouble passing bowel movements, or swelling in the legs. 

Is black period blood normal? 

Black period blood at the beginning of your period or towards the end is very normal. Unless it’s accompanied by any of the symptoms mentioned above, there’s little cause for concern. A period often starts with bright red blood that gradually darkens towards the end.

It’s also very common to have black vaginal discharge after giving birth. This postpartum discharge (known as lochia) is how the body naturally expels excess fluids and tissues from the uterus as part of the postpartum healing process after delivery. If you have any concerns about the black discharge you are experiencing during your postpartum recovery, be sure to mention it to your physician. It never hurts to have a medical professional verify that everything is in order and there are no signs of infection or disease.

Should I be concerned if my period blood is black? 

If you experience black vaginal discharge during your normal period cycle or during postpartum recovery, then you should not be concerned unless you experience additional symptoms along with it. However, if you have black period blood at any other time, you should contact your doctor as it could be a sign of infection or other problem.  

Is there anything I can do about black period blood? 

The available treatment options for black period blood will vary depending on what the cause is.

If the black blood is a result of a foreign object being stuck in your vagina or other type of vaginal blockage, a medical professional will need to remove the object as soon as possible. Do not try to remove the object on your own as you may accidentally injure yourself or push the blockage up further into your vagina. Depending on the severity of the blockage, surgery may be required. You may also be prescribed antibiotics to help combat any infection.

If you have contracted an STI or other type of infection, antibiotics can help fight the symptoms or even cure you completely.

In more rare cases where black period blood is an early indication of cervical cancer, you may receive a combination of surgery, chemotherapy, and radiation to fight the cancer. This treatment will depend entirely upon the severity of the cancer and your doctor’s recommendations for your unique situation. In most instances, however, black period blood is a natural part of your menstrual cycle and the healing process of your uterus after giving birth and it will resolve itself on its own without medical intervention.

How Proof Can Help: Leak proof protection with Proof undies

No matter what color your period blood is, managing the flow can be a pain and the occasional leak is bound to happen. With Proof, you can say goodbye to unreliable panty liners and awkward situations by using our leak proof undies for maximum period protection. With our patented Leak-Loc® technology, each pair of undies can hold up to 10 teaspoons or about 5 tampons worth of liquid. Absorbent, odor-fighting, and comfortable, these stylish undies can handle even the heaviest flows.

Browse our collection of Proof period undies online! 


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