Rates of life-threatening bleeding in infants have risen sharply since 2017 as parents increasingly decline protective newborn doses of vitamin K, according to two nationwide studies published on November 5, 2026. Researchers analyzed millions of electronic health records and found that climbing refusal rates coincide with a wave of vaccine hesitancy and eroding public health trust.
Infants are born with deficient levels of vitamin K because the nutrient does not transfer efficiently across the placenta, and breast milk contains low concentrations. Newborns face severe risks of vitamin K deficiency bleeding, which can trigger spontaneous internal bleeding, without the prophylactic injection recommended by the American Academy of Pediatrics since 1961.
Studies Track Millions of Births and Climbing Refusal Rates
Kristan Scott and colleagues at the Children’s Hospital of Philadelphia analyzed electronic health records for more than 5.2 million U.S. infants born between 2017 and 2025 using the Epic Cosmos database, discovering that the proportion of newborns skipping the vitamin K shot more than doubled from 3.1% to 6.8% (JAMA study). Two separate investigations published in JAMA and JAMA Pediatrics on November 5, 2026, quantified the nationwide shift. Infants who missed the injection faced a 47% higher overall bleeding risk during their first six months of life and more than twice the risk of bleeding in the brain compared to infants who received the prophylactic dose.
Elizabeth Wolf, a pediatrician at Children’s Hospital of Richmond, led a research team that examined medical records for more than 11 million infants born between 2017 and 2025 (JAMA Pediatrics study). That analysis revealed that the percentage of newborns receiving injectable vitamin K dropped from 97.7% to 95.0%. The rate of vitamin K deficiency and vitamin K deficiency bleeding increased by 216% and 347%, respectively, over the same multi-year span.
Parents Reject Routine Infant Supplements Amid Growing Medical Skepticism
Steven Woolf, an epidemiologist at Virginia Commonwealth University and a co-author of the VCU study, pointed to the direct fallout of parents stepping away from decades of established clinical standard care. Physicians emphasize that the simple intramuscular injection is a benign vitamin supplement rather than a vaccine, yet it has become caught in skepticism toward medical interventions.
Now we’re stepping away from that and we’re seeing the consequences,
Steven Woolf, an epidemiologist at Virginia Commonwealth University
Woolf and his co-authors noted that the steep climb in infant complications developed against the backdrop of eroding trust in public health in the wake of the COVID-19 pandemic, increasing vaccine hesitancy, and growing parental unease about interventions in newborns.
The peak in bleeding events during 2025 coincided directly with these cultural shifts, with researchers noting that the rate in 2025 was approximately double what it was in 2024.
As with childhood immunizations, vitamin K prophylaxis may be a victim of its own success; the rarity of (vitamin K deficiency bleeding) may leave today’s families largely unaware of its grave consequences,
the VCU researchers wrote. Medical experts suggest that the efficacy of the intervention has masked its necessity for modern families. Elizabeth Wolf added that the current trajectory mirrors other preventable setbacks:
Similar to the recent measles outbreaks, we are seeing the real-world implications of growing mistrust of doctors and public health professionals,
Elizabeth Wolf, a pediatrician at Children’s Hospital of Richmond
Pediatricians Face Longer Counseling Hours as Refusal Rates Climb
Pediatricians on hospital floors report that counseling hesitant parents has extended clinical workflows. Lawmakers called on the CDC to track vitamin K compliance and deaths from vitamin K deficiency bleeding and to make the information publicly available in response to an investigation ProPublica published last May.
Truveta data analyzed exclusively for Reuters indicated that vitamin K refusals accelerated by more than 57% in the first half of 2026 alone. Continued monitoring is vital as refusal rates climb further. As Laura R. Kair, MD, MAS, of the University of California Davis School of Medicine noted in an accompanying journal editorial, communicating the risk of bleeding with vitamin K declination just got a little easier.
Earlier coverage: US Parents Opt for Earlier Measles Shots Amid Outbreaks