Vitamin K deficiency may cause unexpected bleeding (0.25% to 1.7% incidence) during the first week of life in previously healthy-appearing neonates (classic hemorrhagic disease of the newborn [HDN]). The efficacy of neonatal vitamin K prophylaxis (either oral or parenteral) in the prevention of classic HDN is firmly established. It has been the standard of care since the recommendation by the Committee on Nutrition was adopted as policy by the American Academy of Pediatrics in 19611
Late HDN, a syndrome defined as unexpected bleeding due to severe vitamin K deficiency in infants aged 2 to 12 weeks, occurs primarily in exclusively breast-fed infants who have received no or inadequate neonatal vitamin K prophylaxis. In addition, infants who have intestinal malabsorption defects (cholestatic jaundice, cystic fibrosis, etc) may also present with late HDN. The rate of late HDN (often manifested by sudden central nervous system hemorrhage) ranges from 4.4 to 7.2 per 100 000 births based on reports from Europe and Asia. When a single dose of oral vitamin K has been used as neonatal prophylaxis, the rate has decreased to 1.4 to 6.4 per 100 000 births. Parenteral neonatal vitamin K prophylaxis prevents the development of late HDN, with the rare exception of infants with severe malabsorption syndromes. Oral regimens that have a similar efficacy as parenteral vitamin K in prevention of late HDN include the repeated administration of oral vitamin K1 (Germany) or K2 (Japan) at birth, 1 week, and 2 to 4 weeks.
In 1990 Golding et al2 reported a study of a 1970 birth cohort in Britain in which they noted an unexpected association between childhood cancer and pethidine given in labor and the neonatal administration of vitamin K. Subsequently, Golding and others3 conducted a case-control study designed to examine the risk of cancer associated with intramuscular vitamin K administration among infants born in two hospitals in Avon between 1965 and 1987 and diagnosed with cancer between 1971 and 1989.