A quick look at bleeding disorders & coagulation

Here's a helpful rundown on the rare but serious health conditions known as bleeding disorders.

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Blood clots and coagulation: The basics1

Usually after an injury, our blood will clot to stop any bleeding. But for someone who has a bleeding disorder, the clotting process is more difficult. There can be a risk of excessive bleeding, spontaneous bleeding in the muscles or joints, and other more serious complications.

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What are blood clots?1

Blood clots are clumps of blood that form naturally in the body in response to injury. Blood-clotting factors, also called coagulation factors, are proteins in the blood that work together to help form these blood clots.

Tiny cells in the blood called platelets then stick together around a wound and form a “platelet plug” to patch the injury. The platelets release chemicals to form fibrin, which acts like a super tightly woven fabric, like mesh, to stop the bleeding and form the blood clot (also known as a fibrin clot).2

The clotting process2,3

Clotting step 1.

An injury happens

Clotting step 2.

The blood vessel shrinks so that less blood will leak out

Primary Hemostasis

Primary hemostasis step 3.

Von Willebrand factor (VWF) binds to site

Primary hemostasis step 4.

Platelets bind to VWF

Primary hemostasis step 5.

Formation of platelet plug

Secondary Hemostasis

Secondary hemostasis step 3.

Clotting cascade with FVIII and other clotting factors are activated sequentially

Secondary hemostasis step 4.

Fibrin clot formation to stop bleeding

Fast facts on bleeding disorders

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Bleeding disorders are caused by missing or deficient blood clotting factors.4

Since there are multiple factors along the coagulation cascade, various factor deficiencies are possible, each of which can cause a particular bleeding disorder.2

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Clotting factors are designated by Roman numerals I through XIII.2

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There are many types of factor deficiencies but the most common among these rare diseases are2:

  • Von Willebrand disease
  • Hemophilia A
  • Hemophilia B

Keep exploring

Daughter kissing her mother on the cheek.

What is von Willebrand disease?

Man working on his laptop.

What is hemophilia A?

Nurse comforting the patient.

What is hemophilia B?

  1. Centers for Disease Control and Prevention. What is hemophilia? https://www.cdc.gov/ncbddd/hemophilia/facts.html. Accessed February 15, 2023.
  2. Palta S. Overview of the coagulation system. Indian J Anaesth. 2014 Sep-Oct; 58(5):515–523.
  3. World Federation of Hemophilia. Inherited bleeding disorders. https://elearning.wfh.org/elearning-centres/inherited-bleeding-disorders/#clotting_process. Accessed February 15, 2023.
  4. Goto M, Takedani H, Yokota K, et al. Strategies to encourage physical activity in patients with hemophilia to improve quality of life. J Blood Med. 2016:7:85-98.