Vitamin K and newborn babies

Vitamin K is needed by the body for blood clotting. Older children and adults get most of their vitamin K from bacteria in the gut, and some from their diet. Without enough vitamin K, small cuts can keep bleeding for a very long time, and large bruises can result from minor injuries. Bleeding can also occur in other parts of the body, such as the brain, where it can cause one type of stroke.

Why newborns are at risk#

Babies have very little vitamin K in their bodies at birth. Vitamin K does not cross the placenta to the developing baby, and before birth the gut has no bacteria to make it.

After birth, there is little vitamin K in breast milk, so breastfed babies can be low in vitamin K for several weeks until the normal gut bacteria begin making it. Infant formula has added vitamin K, but even formula-fed babies have very low levels for the first few days.

With low levels of vitamin K, some babies can have very severe bleeding, sometimes into the brain, which can cause significant brain damage. This bleeding is called hemorrhagic disease of the newborn (HDN).

How vitamin K is given#

For many years, newborn babies have routinely been given vitamin K at birth by injection. This has been found to be very safe and highly effective at preventing HDN.

In the past, the injection was given routinely, but many parents received little or no information about why it was given. When some concern about its safety was published in an international journal, there was a considerable outcry. The concern was not really about safety, because the injection was quickly shown to be both safe and effective. Rather, it was about the fact that parents had not been given information about the need for the injection, or the chance to make an informed decision.

For a time, parents were given information so they could make an informed decision, and they were offered the option of vitamin K by drops rather than injection. Two doses of drops were needed for all babies (one at birth and one three to five days later), with a further dose in the fourth week if the baby was breastfed.

During the period when many babies were given vitamin K by drops, a number of babies had severe episodes of bleeding that were probably due to HDN. It became very clear that a single injection of vitamin K is safer and more effective than three separate sets of drops.

Parents have a choice#

Parents do not have to allow their baby to have a vitamin K injection, but it is very strongly recommended that they give permission for it. Vitamin K injections have been given routinely for many years, with no ill effects at the time of the injection or later. Some babies have slight soreness for a day or so at the injection site.

Vitamin K injections remain the best preventive measure for reducing the risk of hemorrhagic disease of the newborn.

Keeping a record#

When a baby is given vitamin K, whether by injection or oral dose, this should be recorded in the child’s personal health record. In many places, parents are given a child health record free of charge after the birth of their baby.

Key points#

• Vitamin K is needed for blood clotting, and newborn babies have very little of it at birth.
• A lack of vitamin K can lead to hemorrhagic disease of the newborn (HDN), which can cause severe bleeding, including into the brain.
• A single vitamin K injection at birth is safe and is the most effective way to prevent HDN.
• Vitamin K can also be given as drops, but this requires several doses and is less reliable than the injection.
• Parents can decline the injection, but it is strongly recommended, and the dose given should be recorded in the child’s health record.

Where to get help#