Hemorrhagic disease of the newborn is a bleeding disorder that usually develops shortly after a baby is born.

A lack of vitamin K causes hemorrhagic disease of the newborn. Vitamin K plays an important role in blood clotting.

Babies usually have low levels of vitamin K for a variety of reasons. Vitamin K doesn't move easily across the placenta from the mother to the baby. As a result, a newborn doesn't have much vitamin K stored up at birth. Also, there isn't much vitamin K in breast milk.

Your baby may develop this condition if:

• A preventive vitamin K shot is not given at birth (if vitamin K is given by mouth instead of as a shot, it must be given more than once and it may not be as effective)
• You take certain anti-seizure drugs

The condition is grouped into three categories:

• Early onset hemorrhagic disease of the newborn is very rare. It occurs during the first hours of birth and certainly within 24 hours. Use of anti-seizure drugs or a blood thinner called coumadin during pregnancy is a common cause.
• Classic onset disease develops in breastfed infants who did not receive a vitamin K shot within the first week after birth. It is also rare.
• The late onset form is seen in infants older than 2 weeks up to 2 months old. It is more common in children who did not receive a vitamin K shot, and in those of Asian descent.

Newborns and infants with the following problems are more likely to develop this disorder:

• Alpha1-antitrypsin deficiency
• Biliary atresia
• Celiac disease
• Cystic fibrosis
• Diarrhea
• Hepatitis