NORMAL LABOR AND ITS MANAGEMENT : Definition of Labor Labor: 5 “P” factors that affect the duration of labor: •> 1) Passenger (fetus): 2) Passage (birth canal): 3) Power (contractions): 4) Placenta: 5) Psychological state of woman: Stages of Labor: The stages of labor are divided into four stages. 1) First Stage of Labor, 2) Second Stage of Labor, 3) Third Stage of Labor, 4) Fourth Stage of Labor 1)