<prompt> Spontaneous bleeding usually occurs when the platelet counts fall below20000uL50000uL100000uL120000uL  <response>: Ans. a 20000uLRef: Robbins 9thpg 662; 8thpg 692In general, the risk of significant spontaneous hemorrhage increases gradually as the platelet count drops to 50x109L and is high at counts 5x109L. So among the options the best answer is 10,000ul. 