What should be the injection site for a newborn's vaccinations?

The vastus lateralis muscle is the recommended injection site for newborn vaccinations due to its accessibility and size. This muscle is located on the outer thigh, making it a safe and effective location for intramuscular (IM) injections in infants.

Selecting the vastus lateralis is particularly important for newborns and young children because they have smaller muscle mass and a thinner layer of subcutaneous fat, which makes it challenging to use other sites safely without risking injury to underlying structures or causing significant pain. The vastus lateralis provides ample muscle tissue for proper absorption of the vaccine and minimizes potential complications associated with injections.

Other sites such as the dorsal gluteal and ventrogluteal areas are less preferred for infants due to the risk of hitting the sciatic nerve and other important structures, as well as the anatomical challenges posed by the smaller body size of newborns. The deltoid muscle is typically avoided in infants since it is underdeveloped and may not provide sufficient muscle mass for IM injections until the child is older. Therefore, the vastus lateralis is the best and safest choice for administering vaccinations in newborns.