Vitamin K helps blood to clot. It is essential to prevent serious bleeding.

Babies do not get enough vitamin K from their mothers during pregnancy, or when they are breast feeding. Without vitamin K, they are at risk of getting a rare disorder called Vitamin K Deficiency Bleeding, or VKDB. VKDB can cause bleeding into the brain, and may result in brain damage or even death.

VKDB can be prevented by giving new babies extra vitamin K. By the age of about six months, they have built up their own supply.

How is vitamin K given?

The easiest and most reliable way to give babies vitamin K is by injection. One injection just after birth will protect a baby for many months. Since about 1980, most newborn babies in Australia have been given a vitamin K injection.

Vitamin K can also be given by mouth. Several oral doses are essential to give enough protection, because vitamin K is not absorbed as well when it is given by mouth and the effect does not last as long.

If you choose vitamin K by mouth, your baby must have three doses:

Dose 1: at birth
Dose 2: usually three to five days later, and
Dose 3: in the fourth week, if the baby is fully breast fed. (Babies fed mainly by formula do not need the third dose)

If your baby vomits within one hour of swallowing the vitamin K, the baby will need to have another dose.

Can all babies have vitamin K?

All babies need to have vitamin K. Very small or premature babies may need smaller doses – your paediatrician will advise you about this if your baby is in Special Care Nursery.

Vitamin K by mouth is not suitable for some babies. Babies who are premature or sick should be given the vitamin by injection. There are two main reasons for this: the very small dose needed is difficult to measure by mouth, and these babies are also more likely to have feeding difficulties. If you choose vitamin K by mouth but your baby is unwell when a dose is due, the baby may need to have the injection instead.

If, while you were pregnant, you took medication for epilepsy blood clots or tuberculosis, you should tell your doctor or midwife. Your baby may not be able to absorb vitamin K by mouth, and may need the injection indeed

Does Vitamin K have any side effects?

Over 30 years vitamin K has been given to new babies in Australia, it seems to have caused no problems.

Previous studies suggested that injections of vitamin K might be linked to childhood cancer, but recent studies have not found any link with cancer at all. The National Health and Medical Research Council has looked carefully at these studies and other evidence, and has concluded that vitamin K is not associated with childhood cancer, whether it is given by injection or by mouth.

Does my baby have to have vitamin K?

This is your choice. However, giving vitamin K to your newborn baby is a simple way of preventing a very serious disease.

Medical authorities in Australia strongly recommend that all babies be given vitamin K. This includes babies who are premature or sick, and babies having surgery (including circumcision).

Parents who decide against vitamin K need to watch very carefully for any symptoms of VKDB.

What should I look out for?

You should always see your doctor or health care worker if your baby has any unexplained bleeding or bruising –this is particularly important if your baby has not had vitamin K. Or if, when your baby is over three weeks old, there are any signs of jaundice (yellow colouring of the ski or whites of the eyes).

Babies with liver problems are particularly at risk, even if they have had vitamin K.

How do I get vitamin K for my baby?

During your pregnancy, your doctor or midwife should ask whether you want your baby to have vitamin K by injection or by mouth, and they will arrange to provide it.

Soon after birth, your baby will have a vitamin K injection or the first dose by mouth. This will be given by a doctor.

If you  have chosen vitamin K by mouth:

  • The second oral dose can be given when your baby has the newborn screening test in the hospital, or by your local doctor or health care worker.
  • You need to remember the important third oral dose when your baby is between 3 and 4 weeks old. Talk to your doctor or health care worker if you need help or advice.

Make sure that your baby’s vitamin K doses are recorded in the baby’s personal health record.

For more information about your baby and Vitamin K, please speak to your obstetrician or midwife.