Blood coagulation tests were performed in 93 newborn infants with different Apgar score at the 1st and 5th minutes of life. The laboratorial determinations were periodically performed at 0, 24 and 48 hours of life. The following tests were performed: bleeding time, whole blood clotting time, prothrombin time, kaolin-cephalin clotting time, thrombin time, dosage of factors I, V, VIII and X, clot retraction, platelet count, englobulin lysis time and the tourniquet test. Immediately after birth, the mean values of the blood coagulation factors were significantly different among the groups, with the exception of the whole blood clotting time and the platelet count. Those differences were due to the presence of the more depressed neonates. Although these results could indicate some degree of hepatic damage, it was apparent that an activation of the blood coagulation mechanisms took place, leading to a consumption coagulopathy. The infants who died (10) presented clinical and laboratorial data suggestive of disseminated intravascular coagulation (DIC). Necroscopic findings of microthrombosis in the liver and in the central nervous system were diagnosed in two infants.