May 6 (Reuters) - Alere Inc ALR.N said it initiated a voluntary recall of certain blood clot test strips in the United States following reports of nine serious adverse events that included bleeding related to the death of three patients.

The test strip, PN 99008G2, measures how long it takes blood to clot in patients taking blood thinner warfarin and is used with Alere's INRatio2 PT/INR monitor.

The health diagnostics and services company said the adverse events were due to significantly different test results between the strip and the local laboratory plasma test. ID:nPn8mfpfy

"The root cause for this issue has not yet been determined; therefore Alere cannot determine the patient conditions or circumstances that may contribute to the discrepancy," the company said.

Alere has asked customers to immediately stop using the test strips. ID:nL2N0E20R8

The company said it has reported the complaints to the U.S. Food and Drug Administration.

Alere shares were unchanged at $35.51 in early trade on the Nasdaq on Tuesday.

(Reporting by Shailesh Kuber; Editing by Sriraj Kalluvila)

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Keywords: ALERE RECALL/BLOODCLOTSTRIPS