title: Effect of one interval vaginal delivery on the prevalence of stress urinary incontinence: a prospective cohort study.
abstract: OBJECTIVE
  To analyze the effect of one interval vaginal delivery on the prevalence of stress urinary incontinence amongst a cohort of nulliparous women.
  
  
  METHODS
  A cohort of 276 nulliparous women without incontinence was recruited consecutively in 1996, after they had vaginal delivery, and were followed-up for urinary incontinence in 2000. The age, obstetric variables of the 1996 delivery (mode of delivery, genital tract trauma, birth weight, epidural analgesia, episiotomy, durations of labor, postpartum urinary retention), and the presence of interval vaginal delivery during the follow-up period were recorded. The obstetric factors and the prevalence of urinary stress incontinence at follow-up were then compared between women with and without interval vaginal delivery. Logistic regression analysis was performed to test the independence of the obstetric variables in the index pregnancy and the presence of one interval vaginal delivery, with urinary stress incontinence being the dependent variable.
  
  
  RESULTS
  A total of 148 (53.6%) women were followed-up. The prevalence of urinary incontinence was 28.6% in women without interval delivery and 21.1% in women with one interval delivery. There was no significant difference in the prevalence of urinary incontinence between the two groups (chi(2) test, P = 0.31). Logistic regression showed that none of the obstetric variables or the presence of one interval vaginal delivery was significantly associated with urinary incontinence.
  
  
  CONCLUSIONS
  One interval vaginal delivery does not increase risk of urinary stress incontinence 4 years after the index vaginal delivery.
authors.affiliation: Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Sha Tin, New Territories, Hong Kong. yipsk@cuhk.edu.hk
authors.forename: Shing-Kai
authors.initials: SK
authors.lastname: Yip
authors.forename: Daljit
authors.initials: D
authors.lastname: Sahota
authors.forename: Allan
authors.initials: A
authors.lastname: Chang
authors.forename: Tony
authors.initials: T
authors.lastname: Chung
mesh_terms: D000328:Adult; D002584:Cervix Uteri / Q000502:physiology; D015331:Cohort Studies; D036861:Delivery, Obstetric; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D010298:Parity / Q000502:physiology; D011446:Prospective Studies; D014550:Urinary Incontinence, Stress / Q000453:epidemiology*; D016055:Urinary Retention / Q000453:epidemiology; D014590:Uterine Contraction