Newborn Bleeding Cases Rise Alongside Vitamin K Shot Refusals
WHO:
NBC News - Dr. Steven Woolf, an epidemiologist at Virginia Commonwealth University, and colleagues studied infant medical records.
NBC News - Dr. Elizabeth Wolf, a pediatrician at Children’s Hospital of Richmond, led the VCU study.
NBC News - Dr. Kristan Scott and colleagues at Children’s Hospital of Philadelphia conducted studies of newborn vitamin K shot refusals.
NBC News - Health Secretary Robert F. Kennedy Jr. was identified as having spent decades sowing mistrust about vaccines before taking the nation’s top health post; NBC News said he later dropped childhood recommendations for six vaccines.
NBC News - Representative Kim Schrier of Washington and Senator Angela Alsobrooks of Maryland, both Democrats, called on the CDC to track bleeding events.
The Washington Post - Scientists published research about infant bleeding and newborn vitamin K shot refusals in JAMA Pediatrics.
WHAT:
NBC News - A 2017 study by Dr. Kristan Scott and colleagues found that more than 5% of U.S. babies did not receive a vitamin K shot in 2024, a 77% increase in refusals since 2017.
NBC News - Woolf said, “Now we’re stepping away from that and we’re seeing the consequences.”
NBC News - Dr. Elizabeth Wolf said, “Similar to the recent measles outbreaks, we are seeing the real-world implications of growing mistrust of doctors and public health professionals.”
NBC News - A Department of Health and Human Services spokesperson said the CDC still recommends newborn vitamin K shots but declined to say whether it would begin tracking refusals or bleeding events.
The Washington Post - The research was released in JAMA Pediatrics.
NBC News - Two studies found that U.S. infant bleeding rates rose alongside increased parental refusals of newborn vitamin K shots; the studies did not prove causation.
NBC News - Vitamin K deficiency bleeding nearly quadrupled in the records studied, while the share of newborns receiving a shot fell from 97.7% to 95%.
NBC News - The study identified 5,217 bleeding events among more than 11 million births.
NBC News - The 2025 bleeding rate was approximately double the 2024 rate, Woolf said.
NBC News - In a study of more than 5.2 million infants, the share without a vitamin K shot rose from 3.1% to 6.8%; infants without the shot had a 47% higher risk of bleeding within six months, more than twice the risk of brain bleeding, and higher risk of death with a bleeding diagnosis during their birth hospitalization.
NBC News - Researchers calculated that one additional bleeding event would occur for every 114 newborns who did not receive the shot.
The Washington Post - Research reported a surge in infant bleeding cases alongside more parents refusing newborn vitamin K injections.
WHERE:
NBC News - The studies examined U.S. infants; the records covered births nationwide.
NBC News - Schrier represents Washington and Alsobrooks represents Maryland.
WHEN:
NBC News - The research examined records from 2017 through 2025; the studies were published in JAMA and JAMA Pediatrics.
NBC News - Truveta’s analysis found vitamin K refusals rose by more than 57% from January through June 2026.
NBC News - Vitamin K injections have been standard newborn care since 1961.
NBC News - The CDC recommendation to give newborns vitamin K shots remains in place.
WHY:
NBC News - Health experts said mixed messages about childhood vaccination recommendations have raised parental doubts about routine newborn treatments, including vitamin K.
NBC News - Researchers said rising refusals coincided with growing vaccine hesitancy, parental skepticism about newborn interventions, and eroding trust in public health after the COVID pandemic.
The Washington Post - Scientists noted that the increase occurred amid growing skepticism around public health, fueled partly in recent years by President Donald Trump’s administration.
HOW:
NBC News - Woolf’s team analyzed medical records for 11 million infants aged six months or younger; Scott’s team analyzed records for more than 5.2 million U.S. infants.
NBC News - Truveta analyzed more than 1 million births nationwide for Reuters.
NBC News - Babies are born without enough vitamin K, which helps blood clot; newborn injections have been standard care for over 60 years.
(UPDATED November 6, 2026 17:04 UTC)
Studies found infant bleeding increased alongside parental refusals of newborn vitamin K shots, though causation remains unproven. Researchers reported bleeding nearly quadrupled as shot coverage declined. The CDC still recommends the injections amid rising mistrust of health guidance.
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(UPDATED November 6, 2026 13:06 UTC)
Two studies found infant bleeding rose as more U.S. parents refused newborn vitamin K shots. Infants missing the shot faced higher bleeding risks, though researchers did not prove causation. The CDC still recommends the injection, standard newborn care for more than 60 years.