Let’s start by defining terms. Growth refers to a change in size. Development refers to an increase in skills or abilities (physical, emotional, social, or intellectual).

How much does a baby grow in the first year?
By the end of the first year, the average baby triples its birth weight. Heredity, feeding habits, and level of physical activity all have an effect on an individual’s weight, however.

The average baby grows about 10 inches (25cm) in height during the first year. Heredity more strongly influences height than weight.

Proportion refers to the size relationship between different parts of the body. A baby’s head and abdomen are proportionally larger than those of an adult, while its arms and legs are proportionally shorter. During the first year, the head grows rapidly to accommodate the developing brain. Over half the total growth of the head occurs during this time.

How does a baby develop in the first year?
Three basic patterns of physical development are explained below.

Head to Foot	Near to Far	Simple to Complex
The head leads development both before and after birth. Muscle control that allows an infant to focus its eyes and lift and turn its head purposefully occurs first. Then, the infant reaches for what it wants with its arms. Finally, the infant crawls or walks to what it wants, using its legs.	Development starts at the trunk and moves outward. At first, infants wave their whole arms at objects they want. Then, they grab at objects with their palms. Finally, they learn to pick up objects with their thumb and fingers.	At first, a newborn must be guided to the breast or bottle to eat. Later, the infant begins to feed itself with its hands. Later, the toddler learns to use a spoon and fork.