The following primary variables were analyzed: parity (nulliparous or multiparous); brith plan (yes or no); type of birth (eutocic [spontaneous; normal ], instrumented, or cesarean); third/fourth-degree tears (yes or no ); Apgar score; and umbilical artery cold blood pH value. Secondary variables were history of previous cesarean (yes or no ), start of labor (spontaneous or induction of labor), epidural anesthesia (yes or no ), and episiotomy (yes or no ). Sociodemographic variables were age, salaried employee (yes or no ), and university education (yes or no ).