Main Causes Of Blood Clotting

Blood Clotting The blood running through our veins fuels our life by performing the most important job of keeping all organs of our body connected. It transports food, oxygen, hormones, protects us against diseases and helps us live to see another day. Blood clotting is the body’s mechanism to prevent the unwelcome blood loss which occurs when a blood vessel is damaged like when we get cuts or bruises.

The mechanism of blood clotting is complicated and involves a substance called ‘thrombokinase’ released by the platelets present at the site of the wound. This substance leads to the formation of sticky threads which form a sort of mesh, which is the blood clot or ‘thrombus’, preventing further outflow of blood. Blood may form clots even without coming in contact with air as happens in a bruise.

Causes Of Blood Clotting

To Prevent Blood Loss

The most common cause of blood clotting is to prevent loss of blood via wounds or damaged blood vessel. Often irregular flow of blood also causes clotting.

injecting of some kind of medicine

Inflamed veins caused by any sort of trauma to the blood vessels like the injecting of some kind of medicine also leads to clot formation.

Bacterial Infection

Blood clotting may also be caused by bacterial infection by ‘staphylococcus’, a bacteria which is generally resides on the skin. Blood clots form in varicose veins and blood vessels in the legs of pregnant woman.

Atrial Fibrillation

Atrial fibrillation is the uneven beating of the upper chamber of the heart. This causes ‘arrhythmia’, or erratic heartbeat which causes irregular flow of blood.

Atrial Fibrillation


As a result of this arrhythmia blood is left behind on the upper chambers of the heart which form clots. These clots lead to heart attacks and strokes. They may even travel to the brain and cause strokes which lead to death.

Malfunctioning Muscles Leading To Venous Thrombosis

When a person goes into shock or becomes the recipient of severe trauma, his/her muscles may stop contracting which leads to a halt in the blood flow to the heart. This leads to accumulation of blood in veins causing the residual blood to form clots. This is called venous thrombosis or clotting in the veins.


Atherosclerotic disease leads to narrowing of arteries due to deposition of substances on its lining. These deposits may rupture leading to the formation of clots at the site of the rupture.



This can be fatal because the newly formed blood clot may block the entire artery, which is now narrower than before, and lead to a blockage in the blood flow to the heart.

Lifestyle Choices

Certain lifestyle choices like excessive smoking, use of contraceptive pills, little or no exercise, lying down or sitting for long periods of time all lead to an increased chance of blood clotting. Genetics, old age and problems like high blood pressure can also result in formation of blood clots.

Formation of blood clots in our bloodstream sounds like a minor event and yet it may lead to fatal strokes and heart attacks which become the cause of our death. Thus blood clots which are essential to prevent loss of excess blood are also extremely hazardous.

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