[Physiologic values of coagulation factors in newborn infants]

Hemorrhagic tendencies are frequently seen in the neonatal period. From the practical point of view, recognition of physiologic deficiencies of coagulation factors and hemostasis is essential, for the differential diagnosis of hemorrhagic syndromes and adequate treatment. Values of coagulation factors in the newborn and comparison of our results and the results of other authors are presented. It seems that there are no essential changes in hemostasis of term infant, but many coagulation factors exhibit deficient clotting activity as like vitamin K-dependent factors (II, VII, IX, X). Values of fibrinogen, F. XI, XII, XIII are decreased. Those factors which physiologically low in the term infant reach normal adult levels in a few weeks, with the exception of factors IX and XI which may require several months to reach normal levels. In the same time authors presented the results of coagulation factors in mothers during delivery and term infants, to explain the nature of the disorders. For the investigation of these physiological defects, screening tests can be used.