Newborn Vitamin K Shot Refusals Rise as Studies Find Higher Bleeding Risk

More parents in the United States are declining the routine vitamin K injection given to newborns, and two major studies published in November 2026 have found an association between missing the injection and a higher risk of bleeding during infancy.

A study published in JAMA found that newborns who did not receive intramuscular vitamin K had a 47% higher adjusted risk of bleeding during their first six months than infants who received it. Their risk of intracranial bleeding was more than twice as high.

The research also documented that the percentage of newborns without recorded vitamin K administration increased from 3.1% in 2017 to 6.8% in 2025.

A separate study in JAMA Pediatrics found that recorded cases of vitamin K deficiency and vitamin K deficiency bleeding increased among US infants between 2017 and 2025.

Together, the findings have renewed attention on vitamin K deficiency bleeding (VKDB), a potentially life-threatening condition that can cause internal bleeding, including bleeding in the brain.

The studies do not prove that every recorded bleeding event was caused by vitamin K deficiency. However, their findings add to evidence supporting the longstanding recommendation that newborns receive vitamin K shortly after birth.

What the new vitamin K studies found

The November 5, 2026, research included two separate investigations published in major medical journals.

Although both examined vitamin K administration and infant bleeding, they used different datasets and measured different outcomes.

1. JAMA study found a 47% higher risk of bleeding

The study, titled Nonreceipt of Newborn Vitamin K and Risk of Bleeding, examined medical records for 5,240,780 infants born between 2017 and 2025.

Researchers found that the proportion of newborns without recorded intramuscular vitamin K administration increased from 3.1% in 2017 to 6.8% in 2025.

Across the study population, 234,825 infants, or 4.5%, had no documented administration of the injection.

The researchers compared bleeding outcomes among infants who received vitamin K and those who did not.

Their findings included:

  • Overall bleeding: 288.0 cases per 10,000 infants without documented vitamin K, compared with 185.9 per 10,000 among infants who received it.
  • Adjusted bleeding risk: Infants without the injection had a 47% higher adjusted risk of bleeding.
  • Intracranial bleeding: 33.0 cases per 10,000 infants without vitamin K, compared with 13.2 per 10,000 among those who received it.
  • Adjusted intracranial bleeding risk: The risk was 2.43 times higher among infants without documented vitamin K.
  • Death with a concurrent bleeding diagnosis during the birth hospitalization: 2.9 cases per 10,000 infants without vitamin K, compared with 1.1 per 10,000 among infants who received it.

The final finding is specifically about deaths during the birth hospitalization in which a bleeding diagnosis was also recorded. It should not be interpreted as an estimate of overall infant mortality.

The researchers concluded that nonreceipt of newborn vitamin K was associated with a significantly higher risk of bleeding during the first six months of life.

The study was published in JAMA on November 5, 2026.

Source: JAMA – Nonreceipt of Newborn Vitamin K and Risk of Bleeding

2. JAMA Pediatrics study found an increase in vitamin K deficiency bleeding

A second investigation, published in JAMA Pediatrics on the same day, examined changes in vitamin K administration, vitamin K deficiency and vitamin K deficiency bleeding among US infants between 2017 and 2025.

The researchers used records covering more than 11 million infants in the Epic Cosmos database.

The study found that recorded vitamin K deficiency and vitamin K deficiency bleeding increased during the period examined. The researchers reported a substantial rise in VKDB diagnoses, with the rate nearly quadrupling between 2017 and 2025.

The findings provide a different perspective from the JAMA study.

While the first study examined a broad range of bleeding diagnoses and compared outcomes according to whether infants received vitamin K, the JAMA Pediatrics investigation specifically examined recorded vitamin K deficiency and vitamin K-deficient bleeding diagnoses.

The researchers also acknowledged limitations, including the possibility of incorrect medical coding and incomplete recording of some cases.

The results should therefore be understood as trends in recorded diagnoses rather than proof that every infant bleeding episode was caused by vitamin K deficiency.

Source: JAMA Pediatrics – Vitamin K Deficiency and Associated Bleeding in Infants

A Swedish study found similar risks among infants who missed vitamin K

The November findings are consistent with an earlier study published online in JAMA Pediatrics on July 13, 2026.

That research examined 2,020,302 live births in Sweden between 2003 and 2021.

Researchers found that the proportion of newborns without recorded intramuscular vitamin K administration increased from 0.66% in 2006 to 1.50% in 2021.

The study also found that infants who did not receive the injection had:

  • 1.52 times the adjusted odds of bleeding during infancy.
  • 2.91 times the adjusted odds of intracranial bleeding.

The researchers followed infants through their first six months of life.

Although the Swedish and US studies involved different populations, healthcare systems and periods, their findings were broadly consistent: infants who missed intramuscular vitamin K had a higher associated risk of bleeding.

This international comparison strengthens the evidence supporting newborn vitamin K prophylaxis, while the observational nature of both studies means that the results should not be interpreted as proof of causation in every individual case.

Source: JAMA Pediatrics – Vitamin K Prophylaxis in Newborns and Bleeding in Infancy

What is vitamin K deficiency bleeding?

Vitamin K deficiency bleeding, commonly called VKDB, is a condition in which a baby experiences bleeding because the body does not have enough vitamin K to support normal blood clotting.

Vitamin K helps the body produce proteins needed to form blood clots. Without enough of it, bleeding may continue longer than normal or occur internally.

The bleeding can happen in different parts of the body, including the intestines and brain.

Some cases are visible through bruising or bleeding from the umbilical cord. Others occur internally and may not be noticed until the condition becomes serious.

According to the US Centers for Disease Control and Prevention (CDC), babies who do not receive the vitamin K injection at birth can develop VKDB at any time during their first six months.

The condition is preventable, which is why healthcare authorities recommend vitamin K administration shortly after birth.

Source: CDC – About Vitamin K Deficiency Bleeding

Why are newborn babies given vitamin K?

Babies are born with naturally low levels of vitamin K.

There are several reasons for this:

1. Limited transfer during pregnancy

Only small amounts of vitamin K pass from the mother to the baby through the placenta. As a result, newborns have limited reserves when they are born.

2. Their intestines are still developing

The bacteria that help produce vitamin K in the intestines are not yet established in newborn babies.

This means they cannot depend on intestinal production to provide enough vitamin K during the early months of life.

3. Breast milk contains relatively little vitamin K

Breast milk provides important nutrients and health benefits, but it contains relatively low amounts of vitamin K.

Consequently, exclusive breastfeeding does not provide enough vitamin K to reliably prevent VKDB.

These factors make newborns vulnerable to vitamin K deficiency during the first months of life.

Is the newborn vitamin K injection a vaccine?

No. The vitamin K injection is not a vaccine.

It is a preventive dose of a nutrient that helps the body form blood clots.

Vaccines train the immune system to recognize and respond to infections. Vitamin K administration has a different purpose: it helps prevent bleeding caused by insufficient vitamin K.

The injection is given shortly after birth to provide protection during a period when babies naturally have low vitamin K reserves.

Confusing the vitamin K injection with a vaccine can lead to misunderstandings about why it is given and what it does.

When can vitamin K deficiency bleeding happen?

Healthcare providers generally classify VKDB into three types according to when bleeding begins.

Early VKDB

Early VKDB occurs within the first 24 hours after birth.

It is often associated with certain medications taken by the mother during pregnancy, including some medicines used to treat seizures or other medical conditions.

This form can be severe.

Classical VKDB

Classical VKDB usually occurs between two days and one week after birth.

Possible signs include bruising and bleeding from the umbilical cord or other areas.

Late VKDB

Late VKDB develops between one week and six months after birth. It most commonly occurs between two and eight weeks.

This form is particularly concerning because bleeding can happen internally.

The CDC reports that approximately 30% to 60% of late VKDB cases involve bleeding inside the brain.

Late VKDB can occur without obvious warning signs and may lead to serious complications.

Source: CDC – About Vitamin K Deficiency Bleeding

What are the warning signs of vitamin K deficiency bleeding?

One of the challenges with VKDB is that many affected babies show no obvious warning signs before a serious bleeding event begins.

However, possible symptoms include:

  • Unexplained bruising, especially around the head and face.
  • Bleeding from the nose or umbilical cord.
  • Unusual paleness.
  • Blood in the stool.
  • Black, dark or sticky stools.
  • Vomiting blood.
  • Yellowing of the whites of the eyes after the first three weeks of life.
  • Unusual irritability.
  • Excessive sleepiness.
  • Repeated vomiting.
  • Seizures.

Some of these symptoms can indicate internal bleeding, including bleeding in the brain.

Parents should seek urgent medical assessment if a newborn develops unexplained bleeding, blood in the stool, seizures, unusual drowsiness or other concerning symptoms. Do not wait for additional symptoms to appear.

The absence of visible symptoms does not guarantee that a baby is protected from VKDB.

Is the vitamin K shot safe for newborns?

The vitamin K injection has been used as a preventive treatment for newborn bleeding for decades.

The American Academy of Pediatrics has recommended routine vitamin K administration at birth since 1961.

The CDC describes the injection as a safe and effective way to prevent VKDB.

The standard US recommendation is a one-time intramuscular injection into the baby's thigh shortly after birth. The CDC says it can be delayed for up to six hours to allow immediate bonding and contact between the mother and newborn.

Parents who have concerns about ingredients, side effects or the timing of the injection should discuss them directly with their baby's healthcare provider.

The decision should be based on reliable medical information rather than assuming that the injection is a vaccine or that babies can obtain enough vitamin K naturally.

Sources:

Does breastfeeding provide enough vitamin K?

No. Breast milk contains relatively low levels of vitamin K and does not provide enough to reliably prevent vitamin K deficiency bleeding.

This is why the CDC and American Academy of Pediatrics recommend the vitamin K injection for all newborns, regardless of whether they will be breastfed or formula-fed.

Breastfeeding remains beneficial and is recommended for many health reasons. The vitamin K injection addresses a separate nutritional need that breast milk alone does not reliably meet.

The CDC also does not recommend relying on oral vitamin K as an equivalent replacement for the standard injection. Oral vitamin K is not consistently absorbed and may not provide adequate protection, particularly against late VKDB.

Parents considering alternatives should discuss the risks and available options with a qualified healthcare professional.

Source: CDC – Vitamin K and Breastfeeding

Why are more parents refusing the vitamin K shot?

The recent studies document an increase in nonreceipt, but they do not establish one single reason why parents decline the injection.

Concerns about medical interventions, misinformation online and confusion between vitamin K and vaccines are among the issues being discussed in public health reporting.

Some parents also question whether a newborn needs an injection immediately after birth or whether breastfeeding and other approaches can provide sufficient protection.

These concerns make clear communication important.

Healthcare providers need to explain what vitamin K does, why newborns have low reserves, how VKDB can develop and why the injection is recommended.

A November 5, 2026, commentary in JAMA also highlighted the challenge of communicating the risks of declining vitamin K. It noted that serious outcomes are uncommon, which can make the danger seem theoretical to parents who have never encountered a case.

The authors discussed the finding that approximately 114 infants would need to miss the injection for one additional bleeding event to occur, based on the US study's calculation.

That estimate is a population-level comparison, not a prediction that a particular baby will develop bleeding.

Source: JAMA – Communicating Risk of Intramuscular Vitamin K Declination in the US

What parents should know before declining the injection

Parents have the opportunity to discuss newborn care decisions with their healthcare team.

Before declining vitamin K, they should understand that:

  • Newborns naturally have low vitamin K reserves.
  • Breast milk alone does not provide enough vitamin K to reliably prevent VKDB.
  • VKDB can develop during the first six months of life.
  • Some cases involve internal or intracranial bleeding.
  • Late VKDB may occur without obvious warning signs.
  • The recommended intramuscular injection is designed to prevent these complications.

Parents who are unsure about the injection should ask their pediatrician or maternity care team to explain its benefits, risks and available alternatives.

They should not substitute an unverified online recommendation or supplement schedule for professional medical guidance.

Frequently asked questions

What happens if a newborn does not receive the vitamin K shot?

A newborn who does not receive vitamin K has a higher risk of vitamin K deficiency bleeding. The condition can cause bleeding inside the body, including the brain, and may become life-threatening.

Not every baby who misses the injection will develop VKDB, but the preventive dose substantially reduces the risk.

Does every newborn need a vitamin K injection?

The CDC and American Academy of Pediatrics recommend a one-time intramuscular vitamin K injection for all newborns. The recommendation applies to breastfed and formula-fed babies.

Is vitamin K a vaccine?

No. Vitamin K is a nutrient needed for normal blood clotting. The injection is not designed to prevent an infection or train the immune system.

Can breastfeeding prevent vitamin K deficiency bleeding?

Breastfeeding alone does not provide enough vitamin K to reliably prevent VKDB. Breast milk contains relatively low amounts of the nutrient.

When does late vitamin K deficiency bleeding occur?

Late VKDB can occur between one week and six months after birth, most commonly between two and eight weeks.

Can vitamin K deficiency bleeding cause brain damage?

Yes. VKDB can cause intracranial bleeding. Bleeding inside the brain can result in permanent neurological damage or death.

Is oral vitamin K an alternative to the injection?

Oral vitamin K is not considered an equivalent replacement for the recommended intramuscular injection in US guidance. Its absorption and protection can be inconsistent. Parents should discuss any alternative with their healthcare provider.

What did the November 2026 JAMA study discover?

The study of 5,240,780 infants found that the proportion without recorded newborn vitamin K administration increased from 3.1% in 2017 to 6.8% in 2025. Infants without the injection had a 47% higher adjusted risk of bleeding during their first six months and 2.43 times the adjusted risk of intracranial bleeding.

What the findings mean

The November 2026 studies add important evidence to the discussion about newborn vitamin K administration.

The US research found that nonreceipt increased between 2017 and 2025, while infants without documented administration experienced higher rates of bleeding. A separate investigation found an increase in recorded vitamin K deficiency and VKDB diagnoses. Research from Sweden also found a higher associated risk of bleeding among infants who missed the injection.

The studies have limitations, and observational findings cannot establish that every bleeding event was caused by vitamin K deficiency. Nevertheless, the consistency of the findings supports the importance of newborn vitamin K prophylaxis.

For parents, the central point is that vitamin K is not a vaccine or an optional treatment for an existing illness. It is a preventive nutrient given to protect babies during a period when their natural reserves are low.

The CDC and American Academy of Pediatrics continue to recommend the injection shortly after birth. Parents with questions should speak with a qualified healthcare professional before making a decision.

Medical information notice: This article is for general educational purposes and is not a substitute for medical advice, diagnosis or treatment. Parents should consult a qualified healthcare professional about their newborn's care.

Last updated: November 11, 2026.

Related Articles

Originally published at Flames Nova