4Queenan J T. How to stop the relentless rise in cesarean deliv- eries[J]. Obstetrics and Gynecology, 2011, 118(2 Pt 1) : 199.
5Aasheim V, Nilsen A B, Lukasse M, et al. Perineal tech- niques during the second stage of Labour for reducing perineal trauma[J]. Cochrane Database of Systematic Reviews (On- line), 2011, 7(12): CD006672.
6Feng XL,Xu L, Guo Y,et al. Factors influencing rising cae-sarean section rates in China between 1988 and 2008[J]. Bulle-tin of the World Health 0rganization,2012,90(1):30-39.
7Lung Q, KleineLLi R,Wang Y, et al. High caesarean sectionrate in rural China : Is it related to health insurance (New Co-operative Medical Scheme)? [J]. Social Science &? Medicine,2012,75(4):733-737.