A prospective cohort study of women after primary repair of obstetric anal sphincter laceration

OBJECTIVE: This study was undertaken to prospectively assess subjective anorectal symptoms by questionnaire and to prospectively assess the integrity of the anal sphincter by physical and ultrasonographic examination in women with and without obstetric anal sphincter laceration. STUDY DESIGN: Fifteen subjects who sustained obstetric anal sphincter lacerations at the time of vaginal delivery were matched with 15 control subjects and followed up prospectively. Women underwent physical and ultrasonographic evaluations and answered questionnaires regarding anorectal symptoms at 6 weeks and at 4 months post partum. Data were evaluated with the Fisher exact test, the Wilcoxon exact and signed rank tests, and the McNemar test. RESULTS: On postpartum examination the subjects with lacerations had more separated sphincters and decreased anal resting and squeeze tones with respect to control subjects (P < .05). According to ultrasonographic evaluation the anal sphincters were more commonly disrupted in the laceration group than in the control group (external anal sphincter, 40% vs 20%; P = .43; and internal anal sphincter, 47% vs 7%; P = .035). Subjective rating of fecal incontinence was significantly greater in the laceration group than in the control group (P < .05). There was no correlation between fecal incontinence symptoms and the integrity of the external anal sphincter. At the 4-month visit, fecal incontinence was resolved in 36% of subjects; however, continued anorectal dysfunction was reported by 43% of subjects in the laceration group versus only 7% of the control subjects (P = .08). CONCLUSION: Reports of fecal incontinence were significantly greater among women with a history of primarily repaired obstetric anal sphincter lacerations than among control subjects. Ultrasonographic examination revealed separated anal sphincters in 40% of the women with obstetric anal sphincter lacerations, despite repair at the time of delivery.