Which hormone is significant for temperature regulation during neonatal transition?

The significance of cortisol in temperature regulation during neonatal transition lies in its role in the body's response to stress and the adaptation to extrauterine life. After birth, a newborn must rapidly adjust to a new environment, and cortisol facilitates this transition by promoting the metabolism of fat and protein, which helps in generating heat.

Cortisol also plays a role in promoting the production of surfactant in the lungs, aiding respiratory function, which is essential for maintaining stable body temperature. Newborns are particularly susceptible to hypothermia due to their high surface area-to-volume ratio and limited subcutaneous fat, so the thermogenic effects of cortisol are crucial during the immediate postnatal period.

In contrast, insulin primarily regulates glucose homeostasis rather than temperature. Thyroid hormone does play a role in metabolism and energy expenditure, but its effects on temperature regulation are not as immediate in the neonatal phase. Aldosterone is involved in electrolyte balance and blood pressure regulation but does not have a direct role in thermoregulation during transition to life outside the womb.