1Mahony R,O'Herlihy C,Foley ME.Correlation of perineal outcome at first and second vaginal deliveries[J].Ir Med J,2008,101 (10):302 -4.
2Lowder JL,Burrows LJ,Krohn MA,et al.Risk factors for primary and subsequent anal sphincter lacerations:a comparison of cohorts by parity and prior mode of delivery[J].Am J Obstet Gynecol,2007,196(4):344.e1-5.
3Samarasekera DN,Bekhit MT,Preston JP,et al.Risk factors for anal sphincter disruption during child birth[J].Langenbecks Arch Surg,2009,394 (3):535-8.
4Mikolajczyk RT,Zhang J,Troendle J,et al.Risk factors for birth canal lacerations in primiparous women[J].Am J Perinatol,2008,25(5):259 -64.
5王木兰 王淑娟.软产道裂伤的相关因素及处理.安徽医学,1997,18(6):60-60.
6Eskandar O,Shet D.Risk factors for 3rd and 4th degree perineal tear[J].J Obstet Gynaecol,2009,29 (2):119 -22.