Bleeding: External, Internal, and When Blood Won't Clot

Bleeding is the loss of blood.

Where it happens

• External: outside the body, as from a cut or wound.
• Internal: inside the body, as from an injury to an internal organ.
• As a symptom: some bleeding — gastrointestinal bleeding, coughing up blood, vaginal bleeding — can be a sign of disease.

How bleeding normally stops

After an injury, a blood clot forms quickly to stop the bleeding, then dissolves naturally. Making a clot takes two things in the blood:

• Clotting factors — blood proteins;
• Platelets — a type of blood cell.

When clotting goes wrong

Some people have clotting problems because of another medical condition or an inherited disease. There are two kinds:

Other problems bleeding can cause

• Bruises: bleeding under the skin.
• Stroke: some strokes are caused by bleeding in the brain.
• Severe bleeding may need first aid or a trip to the emergency room.

Sources

Based on "Bleeding," MedlinePlus, U.S. National Library of Medicine; a work of the United States government in the public domain.