Vitamin K and your newborn baby

We advise giving your baby extra vitamin K when they are born.

Vitamin K is a substance that is found naturally in the body. It's important for the normal process of blood clotting, which prevents bleeding in the body.

Newborn babies have low levels of vitamin K in their blood. Sometimes, this causes bleeding. This is called vitamin K deficiency bleeding (VKDB) in newborn babies.

We can prevent VKDB by giving your baby extra vitamin K after they are born.

It is strongly recommended that all newborn babies receive vitamin K soon after birth to prevent VKDB, until they build up their own supplies. 

Symptoms of VKDB

If your baby develops VKDB in the first few months, they may have obvious bleeding:

  • from their umbilical cord stump
  • in their pee (urine)
  • from their bottom
  • from their skin and mucous membranes, such as from the nose and gums

Bleeding might appear as bruises on the skin. There is also a risk of internal bleeding, such as inside the head. 

Risks of VKDB

Babies are more at risk of developing VKDB if: 

  • they were born prematurely (before 37 weeks)
  • they were delivered by forceps, ventouse (suction cap) or caesarean section 
  • they are bruised after birth  
  • they had breathing difficulties at birth
  • you are on certain drugs during your pregnancy, such as anticonvulsants (medicine for epilepsy)
  • they are circumcised

Even if your baby is not at a higher risk, they could still develop a vitamin K deficiency. About 1 in 3 babies with VKDB do not have any of the risk factors.

Bleeding because of a vitamin K deficiency only happens in a very small number of babies (about 1 in 10,000).

The impact of VKDB can be mild. However, in rare cases (7 in 100 babies with VKDB) it can lead to death.

About 30 out of 100 of babies with VKDB are left with a neurological impairment because of bleeding to the brain. 

How vitamin K is given

The best method of giving your baby vitamin K is an injection soon after birth. The injection is given by a midwife into the muscle of your baby’s thigh.  

If you choose an injection, your baby will only need to have this once.

Vitamin K by mouth

If you don’t want your baby to have the injection, vitamin K can be given by mouth, unless your baby cannot accept feeds by mouth.  

Given by mouth, your baby will need 3 doses:

  1. the first dose soon after birth 
  2. a second dose when your baby is around 7 days old (given by your midwife), and
  3. a third dose when your baby is about 6 weeks old (given by your health visitor or GP)

If you are bottle-feeding your baby formula milk, they will only need the first 2 doses, as vitamin K is added to all formula milk. 

How feeding affects VKDB

    Babies who are entirely breastfed are more likely to develop VKDB compared to babies that are bottle-fed. This is because manufacturers add vitamin K to formula milk.

    However, although formula milk contains higher levels of vitamin K than breastmilk, this is not a reason to bottle feed your baby. 

    If you choose not to give vitamin K

    If your baby is given vitamin K, the risk of your baby getting VKDB is 1 in 1,000.

    If you choose not to give them vitamin K, the risk of them getting VKDB increases to 1 in 10.

    As a parent you have the right to refuse. However, we strongly encourage you to allow your baby to have this simple treatment.

    If you do not wish your baby to have vitamin K, please discuss this with your midwife or paediatrician in order to get further information before making your decision.

    Resource number: 2313
    Last reviewed: March 2023
    Next review: March 2026

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