Recent impact of anal sphincter injury on overall Caesarean section incidence

Because of increasing recognition of obstetric anal sphincter injury and faecal incontinence, we examined the recent impact of these indications on our institutional Caesarean section incidence.

Retrospective review of the indications for multiparous Caesarean section was performed at the National Maternity Hospital for the 4 years 2000-2003, inclusive, to identify women in whom previous anal sphincter injury was an indication. Individual charts were reviewed and data regarding the nature and extent of previous anal sphincter injury were obtained.

Among 17 586 consecutive multiparous deliveries, previous anal sphincter trauma constituted the indication for Caesarean delivery in 67 women, representing 0.4% of all multiparae, 2.9% of multiparous Caesarean sections and 1.3% of all Caesarean sections performed. Fifty (85%) of the 67 women who opted for prelabour Caesarean delivery following previous obstetric anal sphincter injury had symptoms of faecal incontinence (mean continence score 5, range 1-17).

Notwithstanding recent increased awareness and documentation, anal sphincter problems represent a small influence on total Caesarean incidence.