Anal incontinence can be caused by vaginal deliveries. This Cochrane review examined whether Caesarian delivery prevents this condition
McLoughlin G (2011) Does Caesarean delivery prevent anal incontinence? Nursing Times; 107: early on-line publication.
- Does Caesarean delivery protect maternal pelvic floor function – where damage may occur during vaginal delivery – to prevent postpartum anal incontinence?
- When is the optimum time following childbirth to assess for anal incontinence?
Anal incontinence is the leakage of faecal material spontaneously – fluid or solid – the passing of flatus, or mucoid discharge.
The condition can be caused by labour and vaginal deliveries. It can occur in the immediate postnatal period and can also persist throughout life.
Caesarean delivery may help prevent anal incontinence by preserving pelvic floor function, while avoiding the direct trauma that may occur during a vaginal delivery.
However, Caesarean section is associated with higher risks than a vaginal delivery, such as admission into intensive care, transfusions, hysterectomy and a longer hospital stay.
A systematic review was undertaken to investigate whether Caesarean delivery prevents anal incontinence.
The review looked at 21 non-randomised controlled trials. It included 31,198 births, of which 6,028 were Caesarean and 25,170 were vaginal deliveries. While a large number of deliveries were included in this review, many of the studies were small and may not have had sufficient statistical power to demonstrate a benefit.
The intervention of interest was Caesarean delivery compared with vaginal delivery. Anal incontinence – both faecal and flatus – was the main outcome of
concern and was measured by a validated anal continence assessment instrument and a self-reporting questionnaire.
Meta-analysis was not possible. The review incorporated bias measures, such as adjustments for age and parity, pregnancy and delivery history, a separate analysis of emergency and elective Caesarean sections, and the timing of assessment of pelvic function and continence.
Summary of key evidence
No studies showed a significant benefit of Caesarean delivery over vaginal delivery in relation to continence or flatus.
All studies compared anal incontinence following Caesarean delivery versus vaginal delivery. Of the 21 studies, only two showed Caesarean delivery had a protective effect.
Some studies merged faecal matter and flatus as a single outcome measure when using a continence assessment tool so the results of anal incontinence post-vaginal delivery varied from 1% to as high as 48%.
Six studies compared emergency versus elective Caesarean delivery. These studies separated pregnancy factors from the influence of labour on pelvic floor function. There was no significant difference in faecal incontinence between women having either type of Caesarean delivery. There was also no significant difference in faecal incontinence between an elective Caesarean delivery and a vaginal delivery.
Women who had given birth one or more times had significantly higher rates of faecal incontinence than those who had never had a baby, regardless of type of delivery. This demonstrates an association between pregnancy itself and increased risk of faecal incontinence.
Evidence from a review of 21 non- randomised studies of average risk women suggested Caesarean deliveries were not more beneficial than vaginal deliveries for preventing anal incontinence.
The timing of assessment for anal incontinence is an important factor in determining the effectiveness of Caesarean delivery over vaginal delivery. When assessment is done at three months postpartum, it is likely the pelvic floor is still trying to repair itself, so the results will not be correct. Continence assessment should be performed at a time remote from the baby’s delivery. NT
To access the full review report, including references, click here
Author Geraldine McLoughlin is lecturer, Catherine McAuley School of Nursing and Midwifery, University College Cork, Ireland, and a member of the Cochrane Nursing Care Field (CNCF)
Nelson RL et al (2010) Caesarean delivery for the prevention of anal incontinence. Cochrane Database of systematic Reviews; Issue 2, Art No: CD006756. DOI: 10.1002/146518578.CD0066756.pub2