02/04/2026
I have had a few questions and also a lot of misunderstanding about vitamin K and its utility and use in newborns. The trend to omit vitamin K has went from less than 3% to over 5% from 2017-2024. It even seems more prevalent now. I'll go over what vitamin K actually does and why we do it.
Vitamin K is a fat-soluble vitamin essential for synthesizing clotting factors II, VII, IX, and X, as well as proteins C and S.Newborns are physiologically deficient in vitamin K due to poor placental transmission, immature hepatic synthesis (30-50% of adult levels), and lack of intestinal bacterial colonization that produces vitamin K.
The American Academy of Pediatrics recommends intramuscular vitamin K prophylaxis (1 mg for infants >1500 g) within 6 hours of birth to prevent vitamin K deficiency bleeding (VKDB). This has been since 1961. VKDB manifests as bleeding from mucosal surfaces, circumcision sites, generalized ecchymoses, intramuscular hemorrhages, and intracranial hemorrhage, with more than 50% of late-onset VKDB cases presenting with intracranial bleeding. Parenteral administration is significantly more effective than oral regimens at preventing late-onset VKDB (occurring 1-3 months after birth), which remains problematic even with multiple-dose oral schedules.
Parental refusal has increased in recent years, leading to a resurgence of VKDB cases.Common reasons for refusal include:
- Concerns about a debunked 1990 study linking vitamin K to childhood cancer (multiple larger studies have found no association with leukemia or other cancers)
- Desire for a "natural" birth without interventions
- Lack of understanding of the indication or belief it is unnecessary
- Concerns about injection pain or preservatives (benzyl alcohol), though no evidence supports toxicity from the small preservative amount
Incidence of VKDB without prophylaxis ranges from 0.25% to 1.7% for early and classic forms, and 4.4 to 7.2 per 100,000 infants for late-onset disease, with infants who do not receive intramuscular vitamin K having an 81-fold increased risk of developing late VKDB compared to those who receive it. A single intramuscular dose at birth has virtually eliminated VKDB. Oral regimens have been explored but adherence is the main issue.
In summary vitamin K and its use has been well studied and is needed to prevent brain bleeds in infants. The risk is small if you choose not to but the risk is there of permanent neurological damage.
If you are pregnant and have questions please ask your pediatrician/OB for their recommendations. I always recommend it and my children had it! Feel free to share with expecting families as there is a lot of bad info out there.
Thank you!
Dr. Parker
References below
1.Evaluating for Suspected Child Abuse: Conditions That Predispose to Bleeding. Carpenter SL, Abshire TC, Killough E, Anderst JD. Pediatrics. 2022;150(4):e2022059277. doi:10.1542/peds.2022-059277.
2. Vitamin K and the Newborn Infant. Hand I, Noble L, Abrams SA. Pediatrics. 2022;149(3):e2021056036. doi:10.1542/peds.2021-056036.
3. Notes From the Field: Late Vitamin K Deficiency Bleeding in Infants Whose Parents Declined Vitamin K Prophylaxis--Tennessee, 2013. MMWR. Morbidity and Mortality Weekly Report. 2013;62(45):901-2.
4. Neonatologists and Vitamin K Hesitancy. Rogers TP, Fathi O, Sánchez PJ. Journal of Perinatology : Official Journal of the California Perinatal Association. 2023;43(8):1067-1071. doi:10.1038/s41372-023-01611-w.
5. Late Vitamin K Deficiency Bleeding in Infancy: The Time to Ensure Effective Prevention. Perrone S, Beretta V, Petrolini C, et al. Nutrition Reviews. 2025;:nuaf214. doi:10.1093/nutrit/nuaf214.
6. Vitamin K Deficiency Bleeding in Infancy. Araki S, Shirahata A. Nutrients. 2020;12(3):E780. doi:10.3390/nu12030780.
7. Oral Neonatal Vitamin K Deficiency Bleeding Prophylaxis in Switzerland (2018-2024), Still Valid Guidelines for Healthy Infants. Laubscher B, Schubiger G, Rizzi M, Swiss Paediatric Surveillance Unit (SPSU). European Journal of Pediatrics. 2026;185(2):82. doi:10.1007/s00431-025-06730-4.
8. Belgian Consensus Recommendations to Prevent Vitamin K Deficiency Bleeding in the Term and Preterm Infant. Fiesack S, Smits A, Rayyan M, et al. Nutrients. 2021;13(11):4109. doi:10.3390/nu13114109.
https://jamanetwork.com/journals/jama/article-abstract/2842444?fbclid=IwRlRTSAPwU1lleHRuA2FlbQIxMQBzcnRjBmFwcF9pZAo2NjI4NTY4Mzc5AAEexSA7S42OKE05AR5wD6L9QTeTuuyvZGzkuSeAjIlxbp8IbHle2HXjv26cJFE_aem_4KCVb7GB6UgqREr_jygi_w
This study evaluates whether the proportion of newborns in the US not receiving intramuscular vitamin K has increased in recent years and identifies factors associated with nonreceipt.
