What is vitamin K?
Vitamin K is a vitamin which occurs naturally in food (especially in liver and some vegetables) and helps to make the blood clot in order to prevent severe bleeding.
At birth all newborn babies have relatively low levels of Vitamin K in their blood (the reason for the low levels is unknown) and these levels are quickly used up in the first few days of life.
Once feeding is established the baby slowly builds up its own stores of Vitamin K.
In a small number of cases the low level of Vitamin K can leave the baby vulnerable to Vitamin K deficiency bleeding (VKDB). This can be prevented when a supplement of Vitamin K is given soon after birth.
What is Vitamin K Deficiency Bleeding (VKDB)?
This is a rare condition where the newborn baby may develop bruising or bleeding as a result of low levels of Vitamin K. The blood loss is not always visible.
What is the risk of VKDB?
The risk of VKDB is very small as it occurs in approximately 1:10,000 full-term babies if they do not receive extra vitamin K. This small risk is almost eliminated when a baby is given a Vitamin K supplement.
Which babies are at greater risk?
It is not possible to identify all babies who will develop VKDB. However, some babies are at greater risk, including:
- Those who are born premature
- Those who are born by forceps or ventouse
- Those who feed poorly or find it hard to absorb feeds properly
- Those who have underlying liver disease that may show as prolonged jaundice
- VKDB in the first 24 hours after birth is also more common in mothers on certain drugs, such as anti-convulsants
- Bleeding happens unpredictably in some babies and it is not possible to identify which babies will be at risk with absolute certainty. Of the babies who suffer bleeding, about a quarter have no evident risk factor.
Bottle fed babies have greater protection from VKDB as Vitamin K is added to artificial formula baby milk.
However, the undoubted benefits of breastfeeding greatly outweigh this small increased risk to breastfed babies – this is why Vitamin K supplements are recommended for ALL babies.
How is vitamin K given?
Vitamin K is given by injection into the muscle of the baby’s thigh. This way of giving Vitamin K is recommended by both the Department of Health and The National Institute for Health and Clinical Excellence (NICE).
Are there any risks?
The Department of Health recommends that all newborn babies are given a Vitamin K supplement at birth.
The risk of VKDB can be virtually eliminated by the administration of Vitamin K in the first 24 hours of life, as this is the period of particular risk.
The injection may be uncomfortable for your baby for a short period and this may be upsetting. You can comfort your baby by giving them a cuddle.
What happens if I don’t want my baby to have the injection?
If you prefer your baby not to have this injection, Vitamin K can be given by mouth.
The disadvantages of this are:
- Your baby will need to receive three doses for this to be effective
- Repeat doses will be needed at one week and one month, these will be given by the GP or alternatively the mother can be shown how to give their baby the final dose, by their midwife
- Studies have shown that it is less effective given by mouth
You may decide that your baby should not receive any Vitamin K. In these circumstances the small risk of bleeding due to VKDB will remain and you should be aware of the warning signs of VKDB.
Warning signs of VKDB
Many babies who later suffer serious bleeding in the brain due to VKDB have had prior minor bleeds from the skin, nose, or mouth.
Any minor bleeds or bruising any time in the first 6 months must be looked at urgently.
Any baby that is still jaundiced after 2 weeks of age should be seen by a doctor – this is even more important if they are not gaining weight, have pale stools and dark urine ,or are ill in any way.
If you have any further queries about Vitamin K your midwife or paediatrician will be pleased to help.
Date of Issue: April, 2022
Review Period: April, 2025