<prompt> All the following effects are produced by inhibitors of prostaglandin synthesis exceptProlongation of bleeding timeProlongation of prothrombin timeProlongation of labourGastric mucosal damage  <response>: Ref:. KDT 6e p186 Prothrombin time is increased by the drugs interfering with the coagulation pathway e.g. warfarin. As cox has no role in coagulation, inhibitors,of PG svnthesis do not prolong PI. However, bleeding time BT is prolonged by the drugs interfering with platelet function. Aspirin increases,.BT by acting as an antiplatelet agent. 