At birth you will be asked whether or not you would like your baby to have Vitamin K. The human body requires Vitamin K in order to make blood clot. When babies are born, their level of Vitamin K is low in comparison to adult levels. Regardless, this level of Vitamin K is usually enough to stop bleeding in most babies.

How is Vitamin K administered?

Vitamin K can be administered either by a single injection at birth, or by three doses of a liquid given orally. The latter is administered at birth, on day four and at four weeks respectively.

Why is Vitamin K recommended?

In around 1 in 10,000 babies, the natural level of Vitamin K at birth is insufficient. If these babies do not receive Vitamin K, around half will suffer a brain haemorrhage (intracranial bleeding) resulting in brain damage and very often death.

When Vitamin K is low bleeding can result. This bleeding is known as Vitamin K Deficiency Bleeding (VKDB). While VKDB is very rare, the likelihood of its occurrence cannot be predicted. For this reason, Vitamin K supplementation has been recommended and practiced since the 1950s.

Are some babies at higher risk of VKDB?

Little is known about how much Vitamin K a newborn needs but we do know some babies are at increased risk of VKDB. This equates to approximately one third of babies including those:

• Born before 37 weeks of pregnancy
• Delivered using medical interventions resulting in bruising, such as forceps, ventouse or caesarean
• Experiencing breathing difficulties and/or oxygen deprivation during or after birth
• Born to mothers taking anticonvulsants, anti-coagulants, or drugs to treat tuberculosis

Historically a slightly elevated rate of VKDB has been observed in breastfed babies and in babies given Vitamin K by mouth rather than via injection. Vitamin K is routinely added to baby formula, which has been thought to account for an elevated rate of VKDB in breastfed babies.

Does this mean breastfeeding puts my baby at greater risk?

The simple answer is – unlikely! It is entirely possible that the elevated rate of VKDB in breastfed babies seen historically could be attributed to feeding practices of the time. Vitamin K levels are higher in colostrum and hindmilk (the milk produced late in a prolonged feed). In the past, babies were not breastfed till some time after birth, and strict schedules were recommended including four-hourly and timed feeds. This quite possibly meant that breastfed babies were deprived of Vitamin K available in colostrum and hindmilk, effectively skewing scientific results.

With breastfeeding now recommended as soon as possible after birth, and mothers encouraged to breastfeed for as long and as often as their baby desires, we should see a reduction in the risk of VKDB in babies that are breastfed.

Does choosing oral administration put my baby at greater risk?

The simple answer is – probably not! It is known that Vitamin K is absorbed less effectively orally than by injection. However, this effect is combated by administering three doses. Routine studies that concluded a higher rate of incidence of VKDB in babies administered Vitamin K orally, were mostly conducted at a time when only one dose was given.

An additional constrain of oral administration is the risk of vomiting. Occasionally babies may vomit after administration of Vitamin K. Whether as a result of the dose itself or the spitting up that many babies do, vomiting quite obviously has the possibility of reducing the amount of the Vitamin K dose retained in the body. Consequently, if a baby vomits shortly after their Vitamin K dose, re-dosing is generally recommended as adequate protection cannot be determined. An injection is generally recommended if vomiting continues.

Parents may choose oral administration for a variety of reasons. These include a desire to avoid inflicting pain on their young baby, and concerns about possible side effects of intramuscular administration. While the evidence for and against the method of administration is inconclusive, research suggests that higher-risk babies benefit from an injection of Vitamin K rather than receiving it orally. Conversely babies not considered higher risk are probably adequately protected by three doses of Vitamin K by mouth.

Will taking Vitamin K during pregnancy and breastfeeding help my baby?

A number of small studies have been conducted to attempt to judge the effects on babies of administering Vitamin K to mothers before and after their baby’s birth. While we know Vitamin K crosses the placenta and is present in breast milk, these studies show no reduction in the instance of VKDB as a result of maternal Vitamin K dosing.

How do I decide?

It is ultimately up to parents to decide what they consider best for their child and it is up to the doctors, midwives and nursing staff to respect these wishes.  There is no conclusive or current evidence of a risk to newborns in administering Vitamin K, although there is certainly speculation about its safety. While the incidence of VKDB is extremely low, when it does occur the result is often catastrophic. Consequently you may wish to administer Vitamin K in order to protect against the unlikely, but none the less present risk of VKDB.

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