Vitamin K for newborns

What is vitamin K?

Our bodies need vitamin K to stop bleeding by forming clots. We get vitamin K from the foods we eat, such as green leafy vegetables, fish, meat, and eggs.

Why does my newborn need vitamin K?

Babies are born with a very small amount of vitamin K, which isn't enough to help their bodies form clots. This can cause bleeding that doesn’t stop. The bleeding can happen inside or outside of the body – including the brain – at any time up to 6 months of age.   

How is vitamin K given to babies?

There are two ways newborns can receive vitamin K:

• A single injection in the thigh muscles within 6 hours of birth, or
• 3 doses by mouth—one at baby’s first feeding, another at 2 to 4 weeks of age, and another at 6 to 8 weeks of age. Your baby must receive all 3 doses to prevent bleeding from lack of vitamin K.

The Canadian Paediatric Society recommends that all newborns get a single does of vitamin K by injection.

Giving vitamin K by mouth is not as effective as by injection. Vitamin K is not absorbed as well when given by mouth and does not last as long. Even if all 3 doses are given, babies who get vitamin K by mouth still have a higher risk of later developing vitamin K deficiency, which can cause bleeding between 2 weeks and 6 months of age.

Is the vitamin K injection safe?

Yes, the vitamin K shot is very safe. There are no side effects. There may be some redness, swelling, or pain at the injection site.

Can’t my baby get vitamin K from my breast milk?

Breast milk contains very low amounts of vitamin K, so babies who only breastfeed will not get enough vitamin K. Even formula-fed babies have very low levels of vitamin K for several days.

What about the injection pain? My baby is so little!

To reduce pain from the injection, hold your baby during the vitamin K shot. You can also try breastfeeding at the same time to comfort your baby.