title: Evidence against vitamin K deficiency in normal neonates.
abstract: Umbilical cord plasmas from 24 normal full-term neonates were studied. We confirmed the prolonged prothrombin time and low levels of Vitamin K dependent clotting factors previously described (1), but using a number of recently developed immunological and coagulation techniques we could find no evidence of vitamin K deficiency. We conclude that the decreased levels of vitamin K dependent clotting factors of normal neonates are the result of decreased synthesis by the immature liver and that it is questionable whether vitamin K prophylaxis is necessary for these infants.
mesh_terms: D001779:Blood Coagulation Factors / Q000096:biosynthesis; D005164:Factor IX / Q000032:analysis; D005167:Factor VII / Q000032:analysis; D005170:Factor X / Q000032:analysis; D005312:Fetal Blood / Q000032:analysis; D006801:Humans; D007231:Infant, Newborn; D008099:Liver / Q000378:metabolism; D011516:Prothrombin / Q000032:analysis; D011517:Prothrombin Time; D014813:Vitamin K Deficiency / Q000453:epidemiology*
chemical_list: D001779:Blood Coagulation Factors; D005167:Factor VII; D011516:Prothrombin; D005164:Factor IX; D005170:Factor X