• At birth: 18 g/dl
• By the age of 3 months: 10 g/dl
• by one year: 12 g/dl

basal oxygen consumption of a neonate is 7-8 ml/kg per minute

• 2-3 times that of an adult

surface area:body weight ratio of a neonate is around twice greater than that of an adult

• Together with reduced subcutaneous adipose tissue and immature heat producing mechanisms (for example, shivering), they are particularly susceptible to heat loss and hypothermia.

Temperature regulation

• Neonates are homeothermic and vasoconstrict in response to cold.
• There is an increase in triglyceride metabolism in brown fat stores, which is under sympathetic nervous system control.