Protein S deficiency; Protein C deficiency
If your health care provider diagnoses you with this disorder, you should be careful to prevent clots from forming. This can occur when the blood moves slowly in the veins, such as from prolonged bed rest during an illness, surgery, hospital stay, or prolonged reduced activity such as long airplane or car trips.
Schafer AI. Thrombotic disorders: hypercoagulable states. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 182.