Why refusing the vitamin K injection for newborns is risky

Every newborn should have the vitamin K injection soon after birth. All babies are born with low vitamin K, and a few will bleed without it, sometimes into the brain with little warning. One injection in the thigh prevents the classic and late forms of this bleeding, and large studies have found no link with cancer.

What is the vitamin K injection given at birth?

It is a single injection of vitamin K into the thigh muscle, given soon after birth. It prevents a rare but serious condition called vitamin K deficiency bleeding.

The American Academy of Pediatrics first recommended it in 1961, and it has been standard care since.¹ European experts advise that every newborn should receive vitamin K, with the injection as the preferred route.² It takes a second, causes a moment's crying, and protects your baby for months.

Why do newborns need vitamin K?

Because every baby is born with very low vitamin K, and blood cannot clot properly without it. This is normal for all newborns, not a defect.

The reasons are simple:^3,4

• Very little vitamin K crosses the placenta
• The newborn liver has small stores
• Adults make some vitamin K with gut bacteria, but a newborn's gut has few bacteria at first
• Breast milk, for all its strengths, contains little vitamin K

Several clotting proteins made by the liver need vitamin K to work. With too little, bleeding can start with no injury at all.

What is vitamin K deficiency bleeding?

Vitamin K deficiency bleeding (VKDB) is bleeding in a young baby caused by low vitamin K. You may also see its old name, haemorrhagic disease of the newborn.

Doctors divide it into three types by when it appears: early, classic and late.³ Early bleeding happens in the first 24 hours. Classic bleeding happens in the first week.⁴ Late bleeding peaks at 3 to 8 weeks of age.⁴ Vitamin K at birth prevents the classic type well and the late type largely.⁴ The early type is different and needs a plan before birth.

What is early vitamin K deficiency bleeding?

Early VKDB happens in the first 24 hours. It is rare and is usually linked to medicines the mother took in pregnancy that interfere with vitamin K.

These include some anti-epilepsy medicines, some tuberculosis medicines such as rifampicin, and blood thinners like warfarin. Vitamin K given to the baby after birth does not reliably prevent this early type. Oral vitamin K is also not suitable for these babies.² If you take any of these medicines, tell your obstetrician and paediatrician well before delivery so a plan can be made. Bleeding in these babies can be severe.

What is classic vitamin K deficiency bleeding?

Classic VKDB appears between day 2 and day 7. It shows as bleeding from the cord stump, blood in vomit or stool, nosebleeds, oozing after circumcision, or unusual bruising.

Without vitamin K, early and classic VKDB together affect about 0.25 to 1.7 percent of babies.³ It is linked to slow or poor feeding in the first week, and small doses of vitamin K at birth prevent it well.⁴ It is usually less dangerous than the late type, but it can still be serious.

What is late vitamin K deficiency bleeding and why is it so dangerous?

Late VKDB appears after the first week, with a peak at 3 to 8 weeks of age. It typically presents as bleeding inside the skull.⁴

This is the form that worries Dr Dutta most. A baby who seemed well becomes pale, sleepy, irritable, vomits, or has a fit. Many survivors have lasting brain injury, and some die. Sometimes there is a small warning bleed first, like a nosebleed, but often there is not.

Without vitamin K, late VKDB affects about 4 to 7 babies per 100,000 in high-income countries.³ In low and middle income countries the figure is far higher, around 80 per 100,000.⁵

Which babies are most at risk of vitamin K deficiency bleeding?

Babies who did not get vitamin K at birth and are exclusively breastfed are most at risk of the late form. Babies with hidden liver disease are at very high risk.⁴

Liver problems such as biliary atresia reduce how much vitamin K the gut can absorb.⁴ Often nobody knows the baby has a liver problem until the bleed happens. One clue is jaundice that lasts beyond 2 weeks, especially with pale stools. Breastfeeding is still the best feeding choice. The answer is to give vitamin K, not to avoid breastfeeding.

How well does the vitamin K injection work?

Very well. In surveillance studies, babies given vitamin K by injection had about 98 percent lower risk of late VKDB than babies who had none.⁵

A CDC report estimated that babies who do not receive the injection are 81 times more likely to develop late VKDB.³ One injection protects against the classic and late types, because the vitamin is released slowly from the muscle. A systematic review by Indian authors concluded that injected vitamin K should be given to all newborns at birth.⁵

Does the vitamin K injection cause cancer?

No. Large studies have found no link between the vitamin K injection and childhood cancer.

In 1992, a British study suggested a possible link with childhood cancer.⁶ This caused real alarm. Since then, much larger studies have looked carefully. An American study found no association with any childhood cancer.⁷ The large United Kingdom Childhood Cancer Study, with more than 2500 children with cancer, also found no link with leukaemia or other cancers.⁸

This is science working as it should. A worrying signal was taken seriously, tested properly, and did not hold up.

Can my baby have vitamin K by mouth instead of the injection?

Oral vitamin K is possible, but it is less reliable. The injection is the preferred route.²

A single oral dose gave much less protection than the injection.⁵ Oral vitamin K works only when several doses are given on time, for example three doses: one at birth, one when the baby is 4 to 6 days old and one at 4 to 6 weeks.² Even then, babies with hidden liver disease may not absorb it.⁴ Oral vitamin K is not suitable for premature babies, unwell babies, or babies whose mothers took medicines that affect vitamin K.² In India, the right oral preparation can also be hard to find. If you still choose oral dosing, plan it with your paediatrician and do not miss a dose.

Does the vitamin K injection hurt my baby?

It causes a brief sting, like any injection. You can make it easier for your baby.

Babies held skin-to-skin during an injection cry for a shorter time.⁹ Ask the nurse to give it while your baby lies on your chest or is breastfeeding. Mild redness at the injection site can happen and settles on its own.

My baby had a gentle birth, so is the risk low?

No. Vitamin K stores are low in every baby at birth, and breast milk contains little vitamin K.⁴ The late form happens because those low stores are not topped up.

In Dr Dutta's view, this means a calm, easy birth gives no protection. A home birth, a water birth or a short labour does not change the baby's vitamin K stores. Nor, as far as we know, does the mother eating more green leafy vegetables.

Is vitamin K deficiency bleeding becoming more common?

In some countries, yes. The American Academy of Pediatrics reports that cases appear to be rising, mainly because more parents refuse the injection.¹

In 2013, doctors in Tennessee reported several babies with late VKDB whose parents had declined vitamin K.³ Dr Dutta understands why parents question medical routines. Questioning is healthy. For vitamin K, the questions have been asked and answered many times, and the answer is clear.

Do premature babies need vitamin K?

Yes. Premature babies need vitamin K too, and the American Academy of Pediatrics statement covers both term and preterm babies.¹

Oral vitamin K is not suitable for premature babies.² Very small babies are often given a smaller injected dose, and your neonatal team will choose the right one.

What other blood problems can newborns have?

Apart from bleeding, the most common newborn blood problems involve red blood cells: too few (anaemia), too many, or cells that break down too fast. Most are mild.

• G6PD deficiency: an inherited enzyme problem that makes red cells fragile and can cause severe jaundice. It is common in South Asia.¹⁰
• Blood group mismatch: the mother's antibodies can break down the baby's red cells, causing early jaundice and anaemia.
• Anaemia: waiting at least a minute before clamping the cord gives babies more blood and better iron stores.¹¹
• Low platelets: platelets help blood clot. Low levels can cause tiny red spots or bruising.

Tell your doctor about any family history of bleeding disorders, thalassaemia or G6PD deficiency.

When should I take my baby to hospital for bleeding?

Whether or not your baby received vitamin K, go to hospital urgently if you notice:

• Bleeding from the cord stump, nose or mouth that does not stop quickly
• Blood in vomit, or black or bloody stools after the first few days
• Bruises without a reason, or tiny red or purple spots on the skin
• Oozing from injection or heel prick sites
• Unusual sleepiness, pallor, a bulging soft spot, repeated vomiting or a fit
• Jaundice beyond 2 weeks, especially with pale stools⁴

Tell the doctor whether your baby had vitamin K at birth. It changes how quickly they will act.