7Lin HC, Xirasagar S. Maternal age and the likelihood of a maternal request for cesarean delivery : a 5-year population-based study. [ J ]. Am J Obstet Gynecol,2005,192:848 - 855.
9Nerum H, Halvorsen L, Sorlie T, et al. Maternal request for cesarean section due to fear of birth : can it be changed through crisisoriented counseling? [ J]. Birth,2006,33(3) :221 -228.