01/12/2025
Why Every Newborn Should Receive Vitamin K₁ at Birth
One of the simplest yet most life-saving interventions in neonatal care is the administration of Vitamin K₁ (phytonadione) immediately after birth.
Yet many parents still don’t fully understand why this tiny injection is so critical.
Why newborns need Vitamin K₁
Newborns naturally have very low levels of Vitamin K, a nutrient essential for the activation of clotting factors. Their livers are still immature, and the good bacteria that later help produce Vitamin K in the gut are not yet established.
This puts babies at risk of a dangerous condition called Vitamin K Deficiency Bleeding (VKDB).
VKDB can lead to unexpected internal bleeding, especially in the brain or gastrointestinal tract. Even small bleeds can cause lifelong disability or be fatal. The heartbreaking part is that VKDB is almost entirely preventable.
How Vitamin K₁ Works (Mechanism of Action)
Vitamin K₁ plays a critical biochemical role:
It acts as a cofactor for the enzyme γ-glutamyl carboxylase.
This enzyme activates key clotting proteins: Factors II, VII, IX, and X, as well as Proteins C and S.
Without this activation, these factors remain nonfunctional, leading to impaired clot formation.
The intramuscular injection provides a reliable, long-lasting supply of Vitamin K that protects the baby for weeks until natural stores build up.
The IM injection is the gold standard
While oral Vitamin K exists, it is less effective and requires multiple doses.
The single intramuscular dose at birth:
Works immediately
Maintains stable levels
Has near-100% protection against VKDB
Bottom line
Vitamin K₁ injection is not optional — it is essential.
A single shot at birth prevents a completely avoidable cause of brain damage and death. As healthcare professionals, policymakers, and advocates, we all have a role in ensuring every newborn receives this life-saving intervention.
