Study Finds Heightened Bleeding Risk in Newborns Who Missed Vitamin K Prophylaxis

• Swedish infants who did not receive the standard intramuscular vitamin K injection at birth showed a higher incidence of bleeding events, including intracranial hemorrhage.
• In a nationwide cohort of more than 2 million live births from 2003 to 2021, those without vitamin K had 1.52‑fold higher odds of any bleeding and 2.91‑fold higher odds of intracranial bleeding within the first six months.
• These findings coincide with growing reports of parental refusal of vitamin K prophylaxis in several countries.

The cohort study, published in JAMA Pediatrics and led by Dr. Eleni Simatou of Karolinska Institutet, demonstrates that Swedish infants who missed the standard intramuscular vitamin K injection faced an increased risk of bleeding—particularly intracranial hemorrhage—within the first six months of life.

Across more than 2 million live births between 2003 and 2021, infants who did not receive vitamin K exhibited higher odds of bleeding overall (adjusted odds ratio = 1.52; 95 % CI 1.27‑1.81) and a markedly greater risk of intracranial bleeding (adjusted odds ratio = 2.91; 95 % CI 2.13‑3.96).

“These results underscore the necessity for ddeidative communication between health‑care providers and parents regarding the essential role of vitamin K in safeguarding newborns against serious, potentially life‑threatening bleeding events,” the authors wrote.

Vitamin K is essential for activating multiple coagulationán factors; inadequate levels can lead to vitamin K deficiency bleeding (VKDB). Infant vulnerability stems from limited transplacental vitamin K transfer, low concentrations in breast milk, and the nascent gut flora’s inability to synthesize the vitamin—this includes the primary bacterial flora such as Lactobacillus.

Despite its proven safety and effectiveness, several countries report increasing parental refusal of vitamin K prophylaxis, leading to a rise in VKDB cases—a trend paralleling recent vaccine hesitancy concerns.

The proportion of infants not receiving the injection fell from 1.32 % in 2003 (1 242 of 94 214 newborns) to 0.66 % in 2006 (667 of 100 429). However, the rate gradually climbed again, surpassing 1 50 % in 2021 (1 619 of 107 915).

Characteristics linked to non‑receipt of intramuscular vitamin K largely matched those of the reference group. Unlike prior U.S. studies that noted a sex difference in vitamin K uptake—potentially tied to circumcision practices—the Swedish cohort, where circumcision is uncommon, found no such association.

These findings reinforce the importance of maintaining adherence to national guidelines. Further research is warranted to elucidate the motivations behind parental refusals and to explore potential correlations with other preventive health decisions-ban multiple-hospital and educational interventions.

The study combined data from the Swedish Medical Birth Register with various national registers, encompassing all live‑born infants at 35 weeks or later from 2003–2021. The primary outcome was a bleeding diagnosis within the first six months of life. Slightly over half (2 020 302) were male; 24 089 had no record of intramuscular vitamin K administration such as providing etc.

While oral vitamin K usage rose over the study period—from fewer than five infants in 2012 to 193 in 2021—oral administration remained rare and is primarily reserved for cases filial or when intramuscular dosing is contraindicated. Oral vitamin K recipients had higher odds of bleeding compared with intramuscular recipients (adjusted odds ratio 2.26; 95 % CI 1.33‑3.84 for any bleeding within six months; 3.74; 95 % CI 1.55‑9.04 for bleeding within the first 28 days).

In home‑born infants, 142 (35.86 %) received intramuscular vitamin K, 254 (64.14 %) did not, but the limited number prevented reliable risk comparisons.

Limitations included potential misclassification in electronic records, incomplete adjustment for confounders such as maternal medication, substance use, or breastfeeding practices, and the observational design, which precludes definitive causal inference, the authors noted.

Source link