Reprinted with permission from the Canadian Paediatric Society

What is vitamin K?

Our bodies need vitamin K to form clots and to stop bleeding. 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. Not having enough can cause bleeding that doesn’t stop because there isn’t enough vitamin K to form a clot. 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 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.

The Canadian Paediatric Society recommends that doctors and healthcare providers give newborns 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. Babies who get vitamin K by mouth have a higher risk of later developing vitamin K deficiency. This can cause bleeding, which can happen 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. 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.

For more tips on reducing the pain click here.

More information from the CPS

• Guidelines for vitamin K prophylaxis in newborns (CPS position statement)

Additional resources

• Facts about Vitamin K Deficiency Bleeding (U.S. Centers for Disease Control and Prevention)