Why is it important not to miss an obstetric anal sphincter injury?

A missed (undiagnosed) OASIS goes unrepaired, leaving a persistent sphincter defect that causes long-term anal/faecal incontinence, perineal pain, dyspareunia, and a poor quality of life - which is much harder to treat later (secondary repair has poorer results).

This is why every woman should have a systematic perineal and rectal examination after vaginal delivery to detect and correctly grade any injury.

Clinical relevance. Systematic post-delivery examination prevents missed OASIS, which otherwise causes long-term incontinence that is harder to treat later.

More Detail

Importance of not missing an OASIS

Missing an OASIS has serious long-term consequences, so systematic detection is essential.

Why it matters

• A missed injury is not repaired at the time, leaving a persistent anal sphincter defect.
• This causes long-term anal/faecal incontinence, perineal pain, dyspareunia/sexual dysfunction, and reduced quality of life.
• Delayed (secondary) repair has poorer outcomes than immediate primary repair, so missing the diagnosis worsens the prognosis.

How to avoid missing it

• Systematic examination after every vaginal birth - a perineal AND rectal examination to detect sphincter involvement and correctly classify the tear.
• Examination by a clinician trained to recognise and grade OASIS.
• Part of the OASI care bundle.

Message

• 'Do not miss an OASIS' - early accurate diagnosis and repair protect long-term continence.