The neonatal period (birth to 1 month) is a time of extensive and ongoing system transition from uterine environment to external world, this includes the initial period after birth which is referred to as the perinatal period. It would seem obvious to say that development does not stop at birth. In fact many systems (cardiovascular, respiratory, gastrointestinal, homeostasis) undergo significant changes at birth, and many others (neural) have not yet completed their development. Note this current project focuses on prenatal development, so postnatal content is not as detailed.Postnatal development can be broadly divided into the age categories of: Neonatal (birth to 1 month), Infancy (1 month to 2 years), Childhood (2 years to puberty), Puberty (12 years to mid-teens) and Young Adult which is a new category (late teens to early twenties). Neonatal care begins as soon as the baby is born. In fact, suctioning of the nose and mouth may take place as the baby is in the process of being delivered—with the head out, and while the mother is taking a pause before the next push. In utero the infant is swimming in amniotic fluid. As he or she comes down the birth canal, the contractions exert pressure on the body and push some of the amniotic fluid out of the lungs. It is this fluid that is suctioned out during those first few moments. Shortly after delivery, the umbilical cord is clamped and then cut. Shortly after clamping, the cord will be checked for the presence of two arteries and one vein. Once the cord is clamped, the baby must breathe and function independently from the mother.