safe motherhood


Vitamin K

Vitamin K is needed to make blood clot. Babies are born with low levels of K but the amount is usually enough to stop bleeding. A few babies do not have enough Vitamin K to prevent bleeding problems. This can be very serious for the baby. Babies who are at risk cannot all be easily identified. The Department of Health recommends that all babies are given Vitamin K soon after birth. Vitamin K can be given by injection or by mouth and parents may want to think about which, if any, they prefer.

Here we outline the evidence on Vitamin K and the signs you should watch out for in your baby.

Can we pick out high-risk babies

Perhaps Vitamin K should only be given to babies at increased risk of HDN? Most people believe that high-risk babies include:

(i) Infants born after less than 37 weeks of the pregnancy.
(ii) Babies whose birth involved the use of forceps, ventouse, and Caesarean operations.
(iii) Babies who had trouble breathing and did not get enough oxygen when they were born.
(iv) Babies whose mothers are taking anti-convulsants, anti-coagulants, or drugs to treat tuberculosis.

This means that about 30% of babies would be thought of as high risk. Some studies suggest that many babies who develop bleeding problems have problems with their liver. It is hard to spot these babies before they bleed.

What is Vitamin K?

Vitamin K is a naturally occurring substance. It is needed to make several factors to help blood clot. Newborn babies have quite low levels of Vitamin K compared with adults. Scientists do not know why. Occasionally, infants develop bleeding problems. The risk of bleeding is highest in the first 13 weeks of life. If bleeding occurs in the first few days of life, doctors call it 'classic bleeding'. If bleeding occurs in later weeks, it is called Haemorrhagic Disease of the Newborn (HDN), or Vitamin K Deficiency Bleeding (VKDB).

HDN is a rare, but very severe disease. It affects about one in 10,000 low-risk babies if they are not given Vitamin K. Half of all babies who bleed haemorrhage into their brain (intracranial bleeding). This often causes brain damage and usually results in ther death of the baby.

How much Vitamin K should babies have?

There has never been a standard policy in the UK about the dose or the way Vitamin K should be administered. Scientists do not know enough to be sure about recommending Vitamin K doses. For example, they don't know the normal newborn levels of clotting factors. They are not sure if the levels in adults are a good guide to newborn levels. Perhaps infant levels of Vitamin K are naturally low for reasons that we do not yet understand? Although scientists are not sure what to recommend, artificial baby milks have Vitamin K added. This means that a baby fed on artificial milk has adult levels of Vitamin K. When a new baby is given Vitamin K by mouth or by injection, levels rise to many times the adult level. Scientists don't know if this is harmful.

Further reading

Department of Health. (2001) Vitamin K information for parents-to-be. London: Department of Health.
This leaflet is available in several languages from Department of Health, PO Box777, London, SE1 6XH and
(1998) Which Vitamin K Preparation for the Newborn? Drug and Therapeutics Bulletin; 36: 3, 17-19.
McNinch, A.W. (1997) The Vitamin K story. Midwives; 110: 1310, 56.
Cornelissen, M. et al. (1997) Prevention of Vitamin K deficiency bleeding: efficacy of different multiple dose schedules of Vitamin K. European Journal of Pediatrics; 156: 1, 126-130.
An abstract of and commentary on this paper is in MIDIRS's Midwifery Digest (September 1997), p365.
A longer article, written in 1998 by Cynthia Clarkson, complete with 47 references is available from the Librarian, NCT, Alexandra House, Oldham Terrace, Acton, London, W3 6NH.

Can Vitamin K injections increase the risks of leukaemia?

There are downsides to intramuscular injections of Vitamin K. These include infection at the place where the injection goes in and bleeding and bruising in the muscle. Mistakes are occasionally made with the injection and the wrong dose or drug is given. The baby feels pain, and according to some studies there is an increased risk of leukaemia.

A recent study calculated a 2.65 increase in childhood leukaemia following intramuscular Vitamin K compared with oral Vitamin K or no Vitamin K at all. But other studies have not found this.

So should your baby have a Vitamin K injection?

Several studies have tried to answer this question and have not resolved it. High-risk babies seem to benefit overall, but if you assume a small risk of leukaemia low-risk babies may not benefit much overall.

What about breastfed babies?

According to studies, HDN was more common among breastfed babies. We know Vitamin K levels are probably higher in colostrum than in mature milk.

Levels are also higher in the milk a baby has once it has been feeding for some time from one breast (hind-milk). In the past in hospitals babies often did not have a chance to breastfeed till some time after birth and strict four hourly feeding routines were usual. This probably meant babies got less Vitamin K than nature intended. Nowadays babies are usually helped to feed soon after birth and mothers are encouraged to breastfeed as often as their baby wants the breast. This should reduce the risk of HDN in babies that are breastfed. There is no evidence to support giving babies artificial milk if the mother wants to breastfeed.

Should the mother take Vitamin K?

Giving Vitamin K to mothers before and after they have their babies has been tried in small-scale studies. Vitamin K does go across the placenta and into breastmilk. But we do not know if it is safe to give women doses of Vitamin K that may be a hundred times more than they would normally eat in one day.

What about Vitamin K that is taken by mouth?

In 1996, an oral form of Vitamin K called Oral Konakion MM (mixed micelles) Paediatric became available for use in the UK.
If breastfed babies have Vitamin K by mouth they should have several doses - two in the first week of life and a third at one month of age. There is no need for further doses after this.

Babies who are high-risk of HDN benefit from Vitamin K by injection. Giving Vitamin K by intramuscular injection probably keeps levels higher longer as a store of the vitamin forms at the injection site.

Breastfed babies in Denmark and Holland are given small weekly or daily doses of Vitamin K. Both countries have low levels of HDN. The small daily dose given in Holland mimics the Vitamin K intake of infants fed on artificial baby milk and avoids huge concentrations. Parents may find it difficult to follow this treatment plan as doses are easy to forget.

What to watch out for

If your young baby bleeds, for example, if you find blood oozing from the cord stump, if bleeding continues for some time after the 'heel prick' blood test, or if your baby has a nose bleed or unexplained bruising, then please talk to your doctor or midwife. These babies need to be checked in case this bleeding is a sign of HND. If your baby has jaundice lasting longer than two to three weeks, you should talk to your doctor or midwife because this may be a sign of liver problems which increase the risk of abnormal bleeding.

How to decide

The evidence suggests that high-risk babies benefit from intramuscular administration of Vitamin K. Breastfed babies probably benefit from low doses of Vitamin K by mouth. There are risks and downsides to both types of Vitamin K. It is up to you to make sure the midwives and doctors that care for you and your baby know your wishes.


In the 1950s and 1960s it became standard practice for all babies to have an intramuscular injection of Vitamin K. Later, in the 1980s, people wondered if it was important to give Vitamin K injections to every baby as HDN is so rare. Single doses by mouth of an unlicensed oral preparation of Vitamin K became popular. Some babies who were thought to be at low risk were given no Vitamin K at all. A UK study, conducted over two years, confirmed that HDN was indeed rare. The study also showed that HDN was more prevalent where the baby had liver disease or was breastfed. Studies suggested a link between intramuscular Vitamin K and childhood cancers.

This meant that more babies were given Vitamin K by mouth. The number of babies with HDN went up slightly as a result. Across the UK, doctors and midwives have different views on what parents should do about Vitamin K.