Why are newborns often administered Vitamin K at birth?

Administering Vitamin K to newborns at birth is primarily done to prevent Haemorrhagic Disease of the Newborn, also known as Vitamin K Deficiency Bleeding (VKDB). Newborns are particularly at risk for this condition because they are born with low levels of Vitamin K, which is essential for the synthesis of certain clotting factors that help blood to coagulate. Without adequate Vitamin K, a newborn's body may struggle to form blood clots, leading to uncontrolled bleeding.

This condition can manifest in various forms, including early onset (within the first 24 hours) and late onset (typically after the first week) forms of VKDB. The preventive administration of Vitamin K at birth effectively reduces the risk of these serious bleeding complications, ensuring that the infant has the necessary Vitamin K levels to promote proper clotting.

Other options, while they may relate to aspects of newborn care, do not reflect the primary reason for Vitamin K administration. Options related to bone growth or immune response do not accurately capture the critical role of Vitamin K in coagulation. Metabolic acidosis is a separate concern not directly addressed by Vitamin K supplementation. Thus, the focused aim of preventing bleeding disorders establishes the necessity of Vitamin K administration in newborns.