Newborns receive a single injection of vitamin K at birth because breast milk is a poor source of vitamin K.
Vitamin k is a fat soluble vitamin.
Vitamin k is present in green leafy vegetables, fishes, tomatoes, avocado, etc.
It is necessary because it controls the bleeding and help in blood clotting in any injuries.
The breast milk does not have a great source of vitamin K that's why babies need vitamin K injection to prevent blood loss.
Thus, Newborns receive a single injection of vitamin K at birth because breast milk is a poor source of vitamin K.
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