Vitamin K at Birth

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Vitamin K at Birth

Vitamin K is essential for the body to be able to manufacture the components of the blood which help it to clot. It is given to newborns at birth because the baby's Vitamin K levels are low and continue to reduce during the first few days of life.


These low levels of Vitamin K at birth make newborn babies susceptible to exessive bleeding if they are injured during the birth and also to Vitamin K Deficiency Bleeding (VKDB) (formerly known as Haemorrhagic Disease).


Why are newborn babies born with low Vitamin K levels?

Vitamin K from the mother's diet does not cross the placenta well. The other form of Vitamin K which is created by healthy bacteria in the gut, is not available to the newborn baby as its gut is sterile at birth. Once the baby's gut has been colonised with the helpful bacteria, its Vitamin K levels will begin to rise slowly. This tends to happen after 3-4 days of feeding.


What is Vitamin K Deficiency Bleeding?

Vitamin K Deficiency Bleeding (VKDB) is divided 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. It is generally confined to infants born to mothers who have received medications that interfere with vitamin K metabolism e.g. anti-seizure drugs or a blood thinner called coumadin. The reported incidence in infants of mothers who have received such medications without vitamin K supplementation is between 6% and 12%.

  • Classic onset disease is also rare,  but more common that late onset VKDB. It is more common in babies who are unwell at birth or who have a delay in beginning feeding delayed onset of feeding. The incidence reported is variable, with rates of 0.25% to 1.5%  in early reports of both sick and well infants to 0 to 0.44% in recent reviews predominantly of well infants. This type of VKDB is usually mild and involves bleeding at the umbilical cord site or circumcision site. However, blood loss can be significant.

  • Late onset disease is seen in breastfed babies older than 2 weeks up to 2 months old. Although late VKDB is again rare (between 0.05% - 0.02%), the consequences can be catastrophic. More than half of infants who develop late VKDB will have bleeding in the brain. The mortality rate for late VKDB is approximately 20% (Shearer 2009; Lippi and Franchini, 2011).

How is Vitamin K given to newborn babies at birth?

For parents who wish to give their newborn baby a dose of Vitamin K, there are two options:

Intramuscular injection route

Vitamin K is given within 1 hour of birth, by injection into your baby's thigh.


  • This is the easiest and most reliable way to protect the baby against VKDB.
  • Eliminates the risk of classic and late VKDB. Australian incidences of VKDB were 0 per 100,000 live births (Cornelissen, 1997).
  • Vitamin K is slowly released over time from the injection site, thus providing sufficient Vitamin K1 until the baby’s Vitamin K levels reach adult levels naturally (6 months)
  • Most cost-effective option for hospitals.


  • Pain for the baby/ distress for parent;
  • Risk of tissue or nerve damage from the procedure.


Oral Route

Vitamin K is given orally as liquid drops given within 1 hour of birth, then at the time of newborn screening (3-5 days), and then a final dose in the 4th week if the baby is fully breastfed. If the baby is bottlefed, this will not be required as most formula milks are supplemented with Vitmamin K.



  • Lowers the risk of classic and late VKDB. Australian incidences of VKDB were 2.5 per 100,000 live births (Cornelissen, 1997).
  • You will need to take your baby to your GP for the final dose at 4 weeks in order to complete the treatment.
  • Avoids the potential risks of the intramuscular injection.


  • Not 100% effective at preventing VKDB (although it is better than nothing).

  • You will need to take your baby to the GP clinic at 3-4 weeks for the final dose.
  • Vitamin K is not as well absorbed via the mouth and the effects do not last as long, so several doses are required.
  • If your baby vomits within one hour of swallowing the vitamin K, the baby will need to have another dose.
  • If your baby is born with difficulties sucking and swallowing for example being premature, this option may not be suitable.
  • Infants with underlying (and sometimes undetected) gallbladder or liver disorders may not be able to absorb the oral Vitamin K.
  • If you took medication for epilepsy, blood clots or tuberculosis during pregnancy, you should tell your doctor or midwife. These medication can interfere with your baby's ability to absorb vitamin K by mouth.

The authors of the most up-to-date review from the Cochrane Collaboration, make the following conclusions about giving newborn babies Vitamin K at birth to prevent classic and late haemorrhagic disease of the newborn (HDN):

  • The injection and the oral route increase the baby's blood clotting abilities at 1-7 days.
  • An intramuscular injection of vitamin K after birth is effective in the prevention of classic HDN.
  • Neither the injection nor the oral route for giving the baby vitamin K at birth have been tested in randomized trials for addressing late HDN.
  • Oral vitamin K, has not been tested in randomized trials for its effect in either classic or late HDN.

(Offringa et al. 2000).



  • Cornelissen, M., R. von Kries, et al. (1997). “Prevention of vitamin K deficiency bleeding: efficacy of different multiple oral dose schedules of vitamin K.” Eur J Pediatr156(2): 126-130. link
  • Lippi, G. and Franchini, M. (2011). Vitamin K in neonates: facts and myths. Blood Transfusion. Jan 2011; 9(1): 4–9. doi:  10.2450/2010.0034-10 link
  • Offringa, M. Puckett, R.M. (2000). Prophylactic vitamin K for vitamin K deficiency bleeding in neonates. Cochrane Database Syst Rev. 2000;(4):CD002776. link
  • Paling, J (1997). Risks with which we are all at home. Risk perspective scale. Published online link
  • Shearer, M. J. (2009). “Vitamin K deficiency bleeding (VKDB) in early infancy.” Blood Rev23(2): 49-59. Click here.Shearer, M. J., S. Rahim, et al. (1982). “Plasma vitamin K1 in mothers and their newborn babies.” Lancet2(8296): 460-463. link
  • WHO ed. (2013). Global Status Report on Road Safety 2013. Supporting a Decade of Action. Official Report. Geneva, Switzerland: WHO World Health Organisation. pp. vii, 1 - 8, 53ff (countries), 244-252 (Table A2), 296-303 (Table A10) link







0.005% to 0.02%


The risk of late onset Vitamin K Deficiency Bleeding in breastfed babies.






0.0001% to 0.01%


The range of risk in everyday activities that most people feel comfortable with (Paling 1997). We know that they come with a remote chance of serious accidents, but we rarely alter our lifestyles to avoid them.








An australian's annual risk of dying in a road accident in Australia (WHO 2013)