【参考文献】

［1］Faltin DL，Sangalli MR，Roche B，et.al.Weil A：Does a second delivery increase the risk of anal incontinence？BJOG：an international journal of obstetrics and gynaecology，2001，108（7）：684-688.

［2］Fynes M，Donnelly V，Behan M，et al.Effect of second vaginal delivery on anorectal physiology and faecal continence：a prospective study.The Lancet，1999，354（9183）：983-986.

［3］Aigmueller T，Umek W，Elenskaia K，et al.Guidelines for the management of third and fourth degree perineal tears after vaginal birth from the Austrian Urogynecology Working Group.Int Urogynecol J，2013，24（4）：553-558.

［4］Barber MD.Towards evidence-based management of delivery following previous obstetric anal sphincter injury.BJOG：An International Journal of Obstetrics & Gynaecology，2014，121（13）：1704-1704.