Birth (calving in livestock and some other animals, whelping in carnivorous mammals) is the act or process of bearing or bringing forth offspring from the uterus. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world. Different forms of birth are oviparity, vivipary and ovovivipary.
Pediatrics (or paediatrics) is the branch of medicine that deals with the medical care of infants, children, and adolescents. A medical practitioner who specializes in this area is known as a pediatrician, or paediatrician. The word pediatrics and its cognates mean healer of children; they derive from two Greek words: παῖς (pais = child) and ἰατρός (iatros = doctor or healer).
In the United States, a pediatrician (US spelling) is often a primary care physician who specializes in children, whereas in the Commonwealth a paediatrician (British spelling) generally is a medical specialist not in primary general practice.