Vitamin K deficiency in infants can cause life-threatening haemorrhages. To prevent this, neonates in the Netherlands receive an oral dose of 1 mg vitamin K directly after birth. In addition, because breast milk contains little vitamin K, breast-fed infants receive a daily dose of 25 micrograms the first three months. Of three female infants aged 4 weeks, 5 months and 3 months, respectively, two developed an intracranial haemorrhage, which caused death in one. In two cases there were signs of a bleeding tendency, but no tests were done because the patients appeared healthy otherwise. The underlying resorptive disorders, cholestasis and fat malabsorption, caused few symptoms and were discovered only after a vitamin K deficiency bleeding had occurred. In an infant with a bleeding tendency, one should consider the possibility of vitamin K deficiency, even if adequate prophylaxis has been given.