①: As evidence has accumulated discounting the direct effect of epidural analgesia on labor, greater emphasis has been placed on the role of the obstetric caregiver as the primary determinant of the risk of cesarean section.
[2] Nageotte MP, Larson D, Rumney PJ, Sidhu M, Hollenbach K: Epidural analgesia compared with combined spinal-epidural analgesia during labor in nulliparous women . N Engl J Med 1997,337:1715-1719.
[3] Bloom SL, McIntire DD, Kelly MA, Beimer HL, Burpo RH, Garcia MA, Leveno KJ: Lack of effect of walking on labor and delivery. N Engl J Med 1998,339:76-79.