A live birth of a human being occurs when a fetus is expelled and separated from the mother's body and subsequently shows some sign of life, such as voluntary movement, heartbeat, or pulsation of the umbilical cord, for however brief a time. In the absence of such sign, the event is considered a stillbirth. This definition was created by the World Health Organization in 1950 and is chiefly used for public health and statistical purposes. Whether the birth is vaginal or by Caesarean section, and whether the baby is ultimately viable, is not relevant to this statistical definition.