In which way does conduction cause heat loss in newborns?

Conduction is the process of heat transfer that occurs directly through contact between surfaces. In newborns, conduction leads to heat loss primarily through contact with cold surfaces. When a newborn comes into contact with an object or surface that is cooler than their body temperature, heat is transferred from the baby to that surface. This can occur with items like metal examination tables, unheated incubators, or even clothing that isn't warm enough.

This form of heat loss is particularly significant in newborns due to their relatively large surface area compared to their body mass and the fact that they have less subcutaneous fat, making them more vulnerable to temperature changes in their immediate environment. Keeping a newborn warm involves minimizing exposure to such cold surfaces and using warm blankets or pre-warmed equipment to prevent conduction heat loss.

The other options, while related to heat loss, involve different mechanisms. Air exposure relates to convection; evaporation pertains to fluid loss in the form of moisture; and increased metabolic activity refers to an internal process that generates heat, thus countering heat loss rather than contributing to it.