Final answer:
Aspirin may have contributed to the development of the patient's qualitative platelet defect.
Step-by-step explanation:
The component of the patient's previous medication regimen that may have contributed to the development of the qualitative platelet defect is Aspirin.
The clotting process in the body involves several clotting factors, including calcium and vitamin K. Aspirin is known to inhibit the function of platelets, which are responsible for forming blood clots. By interfering with platelets, aspirin can disrupt the clotting process and potentially lead to qualitative platelet defects.
Therefore, the use of aspirin in the patient's medication regimen may have contributed to the development of the platelet defect.