This article is about the very young child. Baby” and “Infants and children prenatal through middle childhood free pdf” redirect here.
The term may also be used to refer to juveniles of other organisms. A newborn is, in colloquial use, an infant who is only hours, days, or up to one month old.
When a human child learns to walk, the term “toddler” may be used instead. In British English, an infant school is for children aged between four and seven.
As a legal term, “infancy” continues from birth until age 18. A newborn’s shoulders and hips are wide, the abdomen protrudes slightly, and the arms and legs are relatively long with respect to the rest of their body.
In first world nations, the average total body length of newborns are 35. The Apgar score is a measure of a newborn’s transition from the uterus during the first minutes after birth.
In developed countries, the average birth weight of a full-term newborn is approximately 3. A newborn’s head is very large in proportion to the body, and the cranium is enormous relative to his or her face.
At birth, many regions of the newborn’s skull have not yet been converted to bone, leaving “soft spots” known as fontanels. The two largest are the diamond-shaped anterior fontanel, located at the top front portion of the head, and the smaller triangular-shaped posterior fontanel, which lies at the back of the head.
Later in the child’s life, these bones will fuse together in a natural process. A protein called noggin is responsible for the delay in an infant’s skull fusion. During labour and birth, the infant’s skull changes shape to fit through the birth canal, sometimes causing the child to be born with a misshapen or elongated head. It will usually return to normal on its own within a few days or weeks.
Special exercises sometimes advised by physicians may assist the process. Some newborns have a fine, downy body hair called lanugo.