Platelets are circulating blood cells. They bind to each other and to the damaged vessel wall to prevent excessive bllod loss. Unlike quantitative platelet defects, there is no automated, simple test to diagnose qualitative platelets defects. However, these defects expose to bleeding in a surgical situation and could explain the transfusion inefficiency of some platelet concentrates.

In recent decades, considerable progress has been made in understanding qualitative platelet disorders.

In this project, we propose to submit blood donors to a standardized hemorrhagic diathesis questionnaire and to compare the prevalence of platelet function abnormalities in blood donors with and without hemorrhagic diathesis.

Primary objective specify the prevalence of qualitative platelet disorders in blood donors with i) a clinical history of bleeding diathesis collected through a standardized and validated questionnaire ii) and / or a hematoma (more than 4 cm) that occurred during blood donation.

Secondary objectives to obtain the prevalence of other defects of hemostasis

Inclusion Criteria:

- Any male or female volunteer eligible for the blood donation

Exclusion Criteria:

• Subject with contraindications to blood donation:
• weight <50 kg;
• severe fatigue,
• anemia,
• insulin-dependent diabetes;
• subject treated for epileptic seizures or having followed a treatment whose arrest is less than 14 days old.
• active pregnancy or childbirth less than 6 months old.
• viral disease (eg influenza, gastroenteritis ...) active less than two weeks after the end of symptoms.
• waiting period not respected after certain acts of daily life according to the regulatory criteria set by the EFS
• HIV infection, hepatitis B, hepatitis C