5Hill K, Thomas K, AbouZahr A, et al. Estimates of maternal mortal- ity worldwide between 1990 and 2005 : an assessment of available da- ta[ J]. Lancet,2007,10(13) :1311 - 1319.
6Kanyighe C , Channon A, Tadesse E, et al. Determinants of post-par-tum maternal mortality at queen elizabeth central hospital, b|antyre, malawi: A case-control study 2001-2002 [ J ]. Afr J Reprod Health, 2008,12(3) :35 -48.
7Olsen BE, Hinderake SG, Lie RT, et al. Risk factors for maternal death in the highlands of rural northern Tanzania: a case-control stud- y[J]. BMC Public Health,2008, 8(52) :1 -9.
8Taguchi N, Kawabata M, Maekawa M, et al. Influence of socio-eco- nomic background and antenatal care programmes on maternal mortal- ity in Surabaya, Indonesia [ J ]. Tropical Medicine and International Health,2003,8 (9) :847 - 852.
9Panchal S, Arria AM, Labbsetwar SA. Maternal mortality during hos- pital admission for delivery: A retrospective analysis using a state- maintained database [ J ]. Anesth Analg, 2001,93 ( 1 ) : 134 - 141.