More parents are refusing vitamin K shots for their newborns, according to a study published Monday in the journal Journal of the American Medical Association found. Experts fear the trend could have deadly consequences.
Babies are born with very low levels of vitamin K, a nutrient the body needs for blood clotting, putting them at risk of heavy bleeding early in life. In the early 1960s, US hospitals began giving vitamin injections to newborns within the first six hours of birth to prevent bleeding, including bleeding in the gastrointestinal tract or brain.
Dr. Kristan Scott, a neonatologist at Children's Hospital of Philadelphia and the study's leader, said he and his co-authors noticed increase in the number of parents refusing vaccinations in his own practice, which prompted the research.
Still, Scott says he didn't quite expect the results.
“The increase is not surprising, but the extent of the increase took me by surprise,” he said.
The study analyzed electronic health record data from Epic Systems' Cosmos database, including whether the child received a vitamin K shot. The study included more than 5 million babies born at 403 hospitals in all 50 states between 2017 and 2024. The researchers found that about 4% of children – about 200,000 – born during this time period did not receive a vitamin K shot. This percentage increased from less than 3% in 2017 to more than 5% in 2024. The highest trend was observed among non-Hispanic white children.
The study found that this rate actually began to rise from 2019 to 2020 and accelerated during and after the Covid pandemic.
Scott said there have been no major policy changes regarding vitamin K injections in hospitals or changes in recommendations from medical organizations. That means the increase in children not getting vitamin K shots is almost certainly due to parental refusal, he said.
Reports of the trend predate 2017. 2016 study in the journal. Hospital pediatrics looked at why parents refuse vaccinations.
Widespread disinformation on social networks and growing vaccine skepticism are likely contributing to the increasing number of parents refusing vitamin K shots for their newborns, said Dr. Tiffany McKee-Garrett, an assistant professor of pediatrics at Texas Children's Hospital in Houston, who was not involved in the new study.
“Parents equate vitamin K injections with vaccines,” McKee-Garrett said, adding that a vitamin K shot is not a vaccine but a supplement derived from a plant.
Dr. Ivan Hand, director of neonatology at NYC Health + Kings County Hospitals in Brooklyn, has also noticed this trend in his practice.
“I think this is due to a general distrust of government that probably started in the second half of the 2010s,” said Hand, who was not involved in the new study.
In 2022, Hand became co-author American Academy of Pediatrics Policy Statement about parents who refuse vitamin K vaccinations for newborns.
Newborns who do not receive a vitamin K vaccine are 80 times more likely to have bleeding due to vitamin K deficiency than those who receive the vaccine, according to scientists. Centers for Disease Control and Prevention. Bleeding may occur up to six months after birth.
“We're creating a population of newborns who are at risk of bleeding,” Scott said, adding that this could include anything from bruising to blood loss from cutting the umbilical cord to gastrointestinal bleeding. “Brain bleeding is what we're really worried about; it's essentially a stroke,” he said. “This can ultimately lead to death.”
It is unclear whether the decline in the number of infants receiving the vaccine that doctors are seeing correlates with an increase in bleeding due to vitamin K deficiency in infants.
Hand said he has not seen an increase in his practice, but added that he only sees babies immediately after they are born. Scott said he believes further research will find an increase in bleeding events.
“What we do know is that when infants do not receive vitamin K, they are at increased risk of bleeding,” he said, adding that CHOP has not only seen an increase in vitamin K refusals, but also an increase in bleeding.
In Houston, McKee-Garrett heard reports of bleeding due to vitamin K deficiency, which was extremely rare in the decades after vitamin K shots began being widely administered in the United States.
“This disease is preventable, so we shouldn't be watching it at all,” Hand said.
In some countries, children are given oral doses of vitamin K supplements. However, these formulas may be inconsistent Each baby's digestive system absorbs different amounts of the nutrient, Hand said, adding that breast milk also isn't a good enough source of vitamin K to prevent deficiency. Oral vitamin K supplements also need to be given multiple times, whereas vitamin K injections only need to be given once. Research in Europe also showed that although oral vitamin K supplements may be effective in the first week of life, they may be much less effective in preventing late bleeding due to vitamin K deficiency, which can occur before 6 months of age.
“This late-onset hemorrhage, internal bleeding, has a mortality rate of 20%,” McKee-Garrett said. Some studies have shown that this up to 50%.
Because vitamin K shots have been widely administered in the U.S. for more than 60 years, Hand said parents may not understand the risks of not taking the preventative drug.
“These treatments have been so effective that people don't understand the consequences. They've never seen a baby with heavy bleeding, so they think it doesn't exist,” he said. “But you don’t see it because we’re treating these kids.”
