Normal Labor

Labor is the physiological process by which a fetus is expelled from the uterus to the outside world. The World Health Organization (WHO) defines normal birth as: spontaneous in onset, low-risk at the start of labor and remaining so throughout labor and delivery, the infant is born spontaneously in the vertex position between 37 and 42 completed weeks of pregnancy, and after birth, mother and infant are in good condition. The three main factors which affect the mechanics of active labor are the power (uterine contractions or maternal expulsive forces), the passage (pelvis or soft tissues), and the passenger (the fetus). Labor is divided into three main stages that delineate milestones in a continuous process: the first stage (cervical dilation), the second stage (delivery of the fetus), and the third stage (delivery of the placenta). This book provides a comprehensive review of normal labor along with its mechanism and management, which will be of immense value for obstetricians and allied health professionals.