Vitamin K deficiency bleeding (VKDB) of the newborn, previously known as haemorrhagic disease of the newborn, is a rare form of bleeding disorder that affects newborns and young infants due to low stores of vitamin K at birth. It commonly presents with intracranial haemorrhage with the risk of brain damage or death.

Newborn infants have low stores of vitamin K, and human breast milk has low concentrations of the vitamin. This combination can lead to vitamin K deficiency and later onset bleeding. Vitamin K deficiency leads to the risk of blood coagulation problems due to impaired production of clotting factors II, VII, IX, X, protein C and protein S by the liver. More rarely VKDB can be caused by maternal medicines causing vitamin K deficiency in the newborn.

VKDB can largely be prevented by prophylactic supplementation of vitamin K, which is typically given shortly after birth by intramuscular injection. Most national health organisations recommend routine vitamin K supplementation after birth. Widespread use of this has made this a rare disease.