One of the first things your care provider will want to do after the birth of your baby is give them a vitamin K injection.

The vitamin K injection, often erroneously called a vaccine, is offered to all babies; its purpose is to supplement the Vitamin K deficiency in many newborn babies as it assist the body’s blood clotting capabilities.

Your first thought might be that allowing your baby to have the vitamin K injection is a ‘no-brainer’. After all, you want to do everything you can to ensure the safety and wellbeing of this tiny newborn.

Questioning the necessity of the injection might seem pointless, even if it is still an optional procedure.

As parents, however, you should make your own informed decision about whether to allow the vitamin K injection. So let’s look at the information:

Why Is Vitamin K Offered At Birth?

The vitamin K injection is a routine procedure, offered to all newborns in the first hours after birth.

The purpose of this is to act as a prophylaxis, or prevention, of a condition called Vitamin K Deficiency Bleeding or VKDB, which is the occurrence of bleeding, or haemorrhage, in babies in the first 12 weeks of life. It used to be known as Haemorrhagic Disease of the Newborn (HDN).

VKDB is separated into three different categories, based on the time at which symptoms occur:

Early VKDB happens in the first 24 hours after birth. It is very rare, and bleeding usually happens in the skin, brain, and abdomen.
Classic VKDB happens between 24 hours and 7 days after birth, usually on days 2-3. It is the most common form, and bleeding usually occurs in the gastrointestinal system, umbilical cord site, skin, nose, and circumcision site.
Late VKDB occurs in babies between 2 and 12 weeks of age (usually in weeks 3-8). Bleeding usually occurs in the brain, skin, and gastrointestinal tract.

How Common Is VKDB?

The incidence of early VKDB – in newborns of mothers who take certain drugs, without vitamin K supplementation – varies from 6% to 12%.

The frequency of classic VKDB varies, but the AAP 2003 review estimates it at between 0.25 to 1.7%, with more recent reports putting the rate at to 0% to 0.44%.

The occurrence of late VKDB ranges from between 0.05% to 0.02%, or 1 in 15 000-20 000 infants.

What Are The Risk Factors For VKDB?

It’s important to remember VKDB is a rare occurrence, and can occur in preterm, or full term, babies.

Early VKDB risk factors include:

Maternal use of anti-seizure drugs that interfere with vitamin K metabolism (phenytoin, phenobarbital, carbamezepine, or primidone)
Maternal anti-coagulants (coumadin, aspirin)
Maternal antibiotics (cephalosporins).

Classic VKDB risk factors include:

Poor breastfeeding
Exclusive breastfeeding.

Late VKDB risk factors include:

Low levels of vitamin K in breast milk
Cystic fibrosis
Celiac disease
Chronic diarrhea
A1-antitrypsin deficiency
Hepatitis.

Around 75% of infants who experience late VKDB have an underlying condition that affects their ability to synthesise blood clotting factors, regardless of vitamin K levels.

You can read more here in Vitamin K and Newborns – Everything You Need To Know.

What’s In The Vitamin K Shot?

There are several different brands of the vitamin K injection and, depending on the country where it is administered, the amount of vitamin K is between 1 and 2mg.

This is 20 000 times the normal level of vitamin K in a newborn, and about 100 times the recommended intake for an adult.

The solution contains phytondione, or the synthetic version of phylloquinone (vitamin K1).

Some brands of vitamin K will contain the preservative benzyl alcohol. This preservative has been linked with toxicity in newborns.

Preservative-free brands of vitamin K have Polysorbate 80. This is a surfactant that is used to deliver certain drugs or chemicals across the blood-brain barrier.

A study done on rats several decades ago linked Polysorbate 80 with infertility. Since then, there has been little research into the effects of this preservative on human fertility.

These brands might also contain propylene glycol, which helps prevent moisture in certain medicines. Propylene glycol is generally considered safe, but used in high doses or for prolonged periods can cause toxicity to occur, especially in infants.

One of the greatest concerns parents have is the possibility the injection includes aluminium. The brand Hospira contains a minute amount of aluminium (well under the recommended maximum level), but no other brands of the vitamin K injection contain any aluminium.

Does The Vitamin K Injection Cause Cancer?

A study published in the British Medical Journal in 1990 suggested the risk of cancer was doubled in babies who had received the vitamin K injection at birth. As a result, many parents switched to using the oral vitamin K. During the next few decades, more studies were initiated to look at this potential link.

You might like to read two high quality studies, published in 2002 and 2003, which found there was no convincing evidence that vitamin K injections were associated with a higher risk of childhood leukaemia.

Does Vitamin K Injection Cause Jaundice?

In the mid 1950s there were cases of hemolytic anemia and hyperbilirubinemia severe enough to cause kernicterus (complication of neonatal jaundice). Care providers were administering high doses (50mg) of vitamin K2, and when this was changed to lower dose vitamin K1, this no longer occurred.

Hyperbilirubinemia has only been associated with Vitamin K1 given in extremely high doses (25–30mg). The effect was particularly seen in premature babies, although it was also present in full term newborns. This has not been a problem when vitamin K1 has been given in normal therapeutic doses (0.5–1mg).

What About Birth Trauma?

Many parents worry about the potential for overlooking, or missing, the development of VKDB, if their baby experiences some kind of trauma during birth. Trauma includes pressure on the skull, or bruising from the use of forceps or vacuum, scalpel incisions during c-sections, or scalp fetal monitors.

There is no evidence to show these occurrences increase the risk of VKDB occurring in a newborn. Birth trauma itself doesn’t affect vitamin K intake, absorption, and activation of blood clotting factors.

However, this is worth bearing in mind: babies whose mothers have interventions during labour can experience lethargy from the drugs used. They might also be separated from their mother for some time, interrupting skin to skin, and the early establishment of breastfeeding.

These factors have the potential to interfere with vitamin K being passed to the baby, and to affect the colonising of beneficial bacteria. There is little to no research looking at these possibilities in interventive births.

Can I Prevent VKDB In My Newborn?

Studies have shown the vitamin K injection is the most effective way to prevent classic and late VKDB in newborns (read more here and here).

The oral form of vitamin K lowers the risk of classic and late VKDB, but is not as effective as the injection. In babies fed infant formula fortified with vitamin K, cases of VKDB are virtually unknown.

For many parents, it’s enough to know their baby has received an adequate dose of vitamin K at birth, and they need not be concerned.

Other parents, however, have concerns about giving vitamin K, and look for alternatives. There is some evidence to show supplementation of 5mg of vitamin K daily can raise levels in breast milk, and this most likely raises levels in babies.

However, we can’t determine how this affects newborn risk for VKDB because, in all studies, both mothers and babies were given supplements, and researches haven’t tested how maternal vitamin intake affects rates of VKDB in newborns.

What Are The Signs Of VKDB?

Unfortunately, in most cases of VKDB, there are often only subtle signs before a serious bleeding event. These signs might include:

Low weight for baby’s age, or slow increase in weight
Bruising, particularly around the head and face
Bleeding from nose, or umbilical cord site, or penis, if circumcised
Bleeding from sites where babies have had needles, such as heel prick, or vaccinations
Skin that is paler than before (babies with darker skin might have pale gums)
Stool that has blood present, is black, or dark, or sticky (after meconium has passed)
Vomiting of blood
Irritability, seizures, excessive sleepiness, or excessive vomiting can be signs of bleeding in the brain
Whites of the eyes might turn yellow (usually after 3 weeks)
A lump appearing on the head early might be a haematoma from blood vessels that have ruptured during labour, and usually resolves on its own. If the lump appears later on it could be an intercranial haemorrhage, which is bleeding inside the skull; this is life-threatening.

If care providers suspect your baby has VKDB, they will perform blood clotting tests, and give your baby an injection of vitamin K1. If this stops the bleeding, care providers will confirm the diagnosis as VKDB. There might be a specific treatment plan, depending on the timing and severity of the bleeding, and any potential complications.