Anal and urinary incontinence 4 years after a vaginal delivery

Our purpose was to establish the incidence of anal and urinary incontinence 4 years following vaginal delivery in women with and without obstetric anal sphincter injuries (OASIS).

This was a prospective study of 241 having their first vaginal delivery who had independent verification and repair of OASIS by trained obstetricians. All obstetricians performing OASIS repairs had undergone structured hands-on training and were then directly supervised while repairing OASIS until they were deemed competent to repair independently. Patients were followed up for 4 years with validated bowel and urinary questionnaires. In order to minimise nonresponders, contact details were verified and obtained from their general practitioners, the local primary care trust and electoral roll.

Two hundred and fifty-four women were invited, and 241 (95 %) participated. Fifty-nine (25 %) women sustained OASIS. One hundred and forty-nine were contactable 4 years later, and 86 (58 %) agreed to participate in the study at 4 years. No woman had faecal incontinence, and there was no difference in rates of flatus incontinence prior to delivery up to 4 years postpartum, regardless of whether OASIS occurred or not. Urinary incontinence was more than four times more common after vaginal birth, and this was not affected by whether OASIS occurred and resulted in a significant deterioration in quality of life.

The previously reported higher rates of anal incontinence following OASIS can be minimised up to 4 years after delivery if repaired by trained doctors. There is a significant increase in urinary incontinence following vaginal delivery, and the mechanism for this is not linked to anal sphincter disruption.