1Morkved S, Salvesen KA, Be K, et al. Pelvic floor muscle strength and thickness in continent and incontinent nulliparous pregnant women[J]. Int Urogyneeol J Pelvic Floor Dysfunct, 2004,15(6) :384-389.
3Nygaard I. Urinary incontinence: is cesarean delivery protective? Semin Perinatol,2006 ,30 :267-271.
4Ege E, Akin B, Ahuntug K, et al. Prevalence of urinary incontinence in the 12-month postpartum period and related risk factors in Turkey. Urol Int, 2008,80 : 355 -361.
5Groutz A, Helpman L, Gold R, et al. First vaginal delivery at an older age : Does it carry an extra risk for the development of stress urinary incontinence. Neurourol Urodyn,2007 ,26 :779-782.
6Foldspang A, Hvidman A, Mommsen S, et al. Risk of postpartum urinary incontinence associated with pregnancy and mode of delivery. Acta Obstat Gynecol Scand ,2004,83:923-927.
7Herrmann V, Scarpa K, Palma PC, et al. Stress urinary incontinence 3 years after pregnancy: correlation to mode of delivery and parity. Int Urogynecol J Pelvic Floor Dysfanct,2009, 20 : 281-288.
8Rahn DD, Ruff MD, Brown SA, et al. Biomechanical properties of the vaginal wall : effect of pregnancy, elastic fiber deficiency, and pelvic organ prolapse. Am J Obstet Gynecol,2008,198:590. e1- 6.
9Clark AL, Slayden OD, Hettrich K, et al. Estrogen increases collagen Ⅰ and Ⅲ mRNA expression in the pelvic support tissues of the rhesus macaque. Am J Obstet Gynecol, 2005,192: 1523- 1529.
