3Hess PE, Pratt SD, Soni AK, et al. An association between severe labor pain and cesarean delivery. Anesth Analg, 2000,90:881-886.
4Fogel ST, Shyken JM, Leighton BL, et al. Epidural labor analgesia and the incidence of cesarean delivery for dystocia. Anesth Analg, 1998,87: 119-123.
5Chestnut DH. Epidural analgesia and the incidence of cesarean section: time for another close look. Anesthesiology, 1997, 87:472-476.
6Lieberman E, Davidson K, Lee-Parritz A, et al. Changes in fetal position during labor and their association with epidural analgesia. Obstet Gynecol,2005,105 : 974-982.
7Philip J, Alexander JM, Sharma SK, et al. Epidural analgesia during labor and maternal fever. Anesthesiology, 1999, 90:1271-1275.
8Howell CJ, Kidd C, Roberts W, et al. A randomised controlled trial of epidural compared with non-epidural analgesia in labour. BJOG, 2001, 108:27-33.
9Alexander JM, Sharma SK, McIntire DD, et al. Intensity of labor pain and cesarean delivery. Anesth Analg, 2001,92: 1524-1528.
10Lee BB, Ngan Kee WD, Ng FF, et al. Epidural infusions of ropivacaine and bupivacaine for labor analgesia: a randomized, double-blind study of obstetric outcome. Anesth Analg, 2004, 98: 1145-1152.