Summary: Newborns are born with low stores of vitamin K, a nutrient essential for normal blood clotting. To prevent a serious and potentially fatal condition called vitamin K deficiency bleeding, most hospitals offer a single vitamin K injection at birth. A recent systematic review, to be presented at the American Academy of Neurology’s 78th Annual Meeting, finds a worrying increase in parents refusing this routine newborn protection, putting infants at higher risk of preventable brain hemorrhage and lifelong neurological harm.
The review shows that infants who do not receive the vitamin K shot are far more likely to develop vitamin K deficiency bleeding. This rare but severe bleeding disorder often involves intracerebral hemorrhage — bleeding inside the brain — which can cause permanent disability or death. The analysis also links refusal of the vitamin K injection to broader hesitancy about other newborn preventive measures and to misinformation.
Key facts
- Dramatically increased risk: Babies who do not receive the vitamin K injection were 81 times more likely to develop vitamin K deficiency bleeding.
- Severe outcomes documented: Among cases of vitamin K deficiency bleeding, 63% experienced brain hemorrhages, about 40% suffered long-term neurological disabilities (such as seizures, cognitive impairment, or motor deficits), and roughly 14% died.
- Rising refusal rates: Refusal of the vitamin K shot appears to be growing in some areas. For example, rates in Minnesota nearly doubled from 0.9% in 2015 to 1.6% in 2019, while several birthing centers reported refusal rates exceeding 30%.
- Not a vaccine: Vitamin K is a nutritional supplement given once at birth to prevent bleeding; it is distinct from vaccines. Nevertheless, refusal of vitamin K has been a strong predictor of future vaccine refusal.
- Associated healthcare hesitancy: Parents who refused the vitamin K injection were significantly more likely to decline other newborn protections, including the hepatitis B vaccine and eye prophylaxis.
Source: AAN
Vitamin K is naturally low in newborns because they have limited stores and have not yet developed the gut bacteria needed to produce it. The single intramuscular injection given shortly after birth safely supplies the vitamin necessary for proper clotting until the baby begins producing it naturally or receives it from feeding. Without this early dose, a baby’s blood may not clot properly, which can lead to spontaneous bleeding — sometimes in the brain — with catastrophic consequences.
The systematic review analyzed 25 studies spanning roughly two decades of international data. Researchers examined rates of vitamin K refusal, the incidence and outcomes of vitamin K deficiency bleeding, reasons parents decline the injection, and any association with refusal of other routine newborn interventions.
Geographic findings in the review included refusal rates of 0.2% to 1.3% in parts of the United States during 2018–2019, and rates of 1% to 3% reported in Canada, New Zealand, and Scotland. Some individual birthing centers reported refusal rates above 30%. Health care staff in multiple U.S. hospitals reported perceiving an increase in parental refusal in recent years.
Case series within the review documented severe outcomes among infants diagnosed with vitamin K deficiency bleeding. Approximately 63% of affected babies experienced brain bleeds, about 40% were left with long-term neurological impairments, and around 14% died. These numbers underscore how a single preventive injection can avert catastrophic lifelong consequences.
The review also found strong links between refusal of vitamin K and refusal of other newborn protections. In U.S. data, parents who declined vitamin K were 90 times more likely to refuse both the hepatitis B vaccine and prophylactic eye medication. In Canada and New Zealand, parents who refused vitamin K were substantially more likely to delay or skip routine infant vaccinations by 15 months of age.
Common reasons parents cited for declining the vitamin K injection included worries about pain from the needle, concerns about preservatives, and exposure to inaccurate or misleading information online. Researchers emphasize that the brief discomfort of a single injection is minimal compared with the risk of a preventable intracerebral hemorrhage and its lifelong impact.
Lead author Kate Semidey, MD, of Florida International University, noted that while overall refusal remains uncommon in most hospitals in the United States, the observed increases in some settings are concerning. The review highlights an urgent need for clear prenatal counseling so parents understand the safety and critical protective benefit of vitamin K administered at birth.
A limitation of this review is that it synthesized previously published studies rather than following new cohorts of infants prospectively, so it does not provide individualized risk estimates for any single baby. Still, the pooled findings consistently show that receiving the vitamin K injection substantially reduces the likelihood of a preventable and potentially fatal bleeding disorder.
Key Questions Answered
A: No. Vitamin K is an essential nutrient required for blood clotting. Newborns have very low vitamin K levels and need an initial dose to protect them until they can produce it naturally or obtain it from feeding.
A: Parents commonly cite concerns about pain, preservatives, or information they have found online. Researchers stress that the risk from a single injection is far smaller than the risk of a preventable brain bleed.
A: Without sufficient vitamin K, a baby’s blood cannot clot properly, which may cause spontaneous bleeding. If bleeding occurs in the brain, it can cause an intracerebral hemorrhage, leading to permanent brain injury or death.
Editorial Notes
- This article was edited by a Neuroscience News editor.
- The journal paper referenced in the review was examined in full.
- Additional context and clarification were provided by editorial staff.
About this neurodevelopment research news
Author: Renee Tessman
Source: AAN
Contact: Renee Tessman – AAN
Image: The image is credited to Neuroscience News
Original Research: Findings will be presented at the American Academy of Neurology’s 78th Annual Meeting.