What Does It Mean When You Are Bleeding Black Blood?

What Does It Mean When You Are Bleeding Black Blood?

If blood appears black or dark red, it means the blood has a low oxygen level, notes Dr. Anne Marie Helmenstine for About.com. Bleeding blood of this color by itself is not a cause for alarm since all blood in the veins has relatively low oxygen.

Significantly dark blood may be a sign the blood is no longer in circulation or the blood is in the periphery veins of the body. Blood turns a dark red or even black-looking color when it is deoxygenated, according to Dr. Helmenstine. Humans of both genders may experience dark-colored bleeding when a wound draws blood from a vein. Blood from veins contains the least amount of oxygen of any blood in the body, especially in areas like fingers and toes. It is not uncommon for a person to prick a finger or a mole and see thick dark blood.

It is normal for women who have occasional heavy menstrual cycles to experience the release of black-looking blood, explains WebMD. This happens when a blood clot breaks apart and is released after being out of the body's regular circulation for some time. If a woman experiences regular releases of heavy dark blood during menstrual cycles, medical attention may be required as this could suggest a blood disorder.