[Vitamin K in the neonate: Recommendations update].

Hemorrhagic disease of the newborn is not common but may be very serious, with cerebral, hepatic, or adrenal gland bleeding. Its prevention is based upon vitamin K1 administration from birth. Scientific studies to validate appropriate treatment policies are scarce, with recommendations coming from expert opinions, retrospective studies, or controversies on possible side effects. After analysis of recent literature data, we propose an oral administration of three doses of 2mg of vitamin K1 at birth, at discharge from the maternity ward, and at 1 month postnatal age for term infants. For premature infants born with a birth weight above 1500g, a weekly dose of 2mg up to term equivalent age may be recommended. For premature infants below 1500g, a weekly dose of 1mg up to 1500g body weight, then a weekly dose of 2mg up to term equivalent age seems appropriate. If oral administration is not possible, the intravenous or intramuscular route may be used with a 50% reduction in dosing.