Platelet transfusions

illustration of an orange platelets drop
What are platelets?

Small, disc-shaped cell fragments in your blood. A bag of platelets looks cloudy and yellow.

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What do they do?

Platelets prevent or stop bleeding. If a blood vessel is damaged by trauma, an operation or illness, platelets form a plug which helps stop bleeding. They're held in place by special proteins in blood until the damage is healed. Platelets also contain growth factors that help repair damaged body tissue.

It's hard for Michelle to talk about the first week of Malala's life without getting choked up.

Malala, platelet recipient

With a bit of luck, a lot of platelets, and even more love, Malala recovered from a bad infection to be the bundle of joy she is now.

Malala, platelet recipient

Why might I need a platelet transfusion?

If you have a low platelet count, which is called thrombocytopenia, or platelets that don’t work properly causing bleeding or putting you at a high risk of bleeding. This may be due to:  





bone marrow transplantation


major surgery


liver disease


severe trauma, or


some medications.

There aren’t any options other than a platelet transfusion. Starting and stopping some medication may help lower some people’s risk of bleeding.

Human leucocyte antigen (HLA) compatible platelets

Our human leucocyte antigen type, or tissue type, is inherited from both our parents. There are thousands of human tissue types that exist on the surface of most of our cells including platelets.

Most patients don’t require human leucocyte antigen compatible platelets, but a very small group of patients need their platelets to be specially matched. These patients have human leucocyte antigen antibodies in their blood that can destroy transfused donor platelets. The human leucocyte antigen antibodies can develop during pregnancy, after a platelet transfusion or after organ transplantation.

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Avoid a transfusion

There are some things you can do to lower the chances of needing a transfusion.

Check out these tips
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Receiving a transfusion

Everything you need to know, from what ‘informed consent’ means through to your recovery.

See our transfusion guide