A third- or fourth-degree tear involves the anal sphincter muscles and is also called an obstetric anal sphincter injury (OASI). Care includes repair by an appropriately trained clinician, infection prevention, bowel management and structured follow-up.

Good repair and planned follow-up reduce the risk of long-term pain, infection and bowel-control problems.

Laxatives, pain relief and pelvic-floor rehabilitation are important parts of recovery.

Persistent urgency, leakage, pain or sexual difficulties should be discussed rather than accepted as inevitable.

Original educational diagram for Third- and Fourth-Degree Perineal Tears (OASI) — Original educational diagram created for this topic. It explains the care pathway visually and is not a diagnostic image.

Repair and immediate care

Repair is usually performed in theatre with suitable anaesthesia and lighting. Antibiotics and a bowel-softening regimen are commonly used. Before discharge, patients should understand wound care, pain relief and which symptoms need review.

Recovery and pelvic-floor rehabilitation

Recovery varies. Gentle pelvic-floor work begins when comfortable, and specialist physiotherapy may be recommended. Adequate hydration, stool softening and avoiding straining protect the repair.

Follow-up assessment

Follow-up should ask specifically about flatus or stool leakage, urgency, pain, wound healing, sexual function and emotional wellbeing. Additional tests or referral may be needed when symptoms persist.

Future pregnancy and birth

The next-birth plan is individualised according to symptoms, examination or test results, previous birth details and preference. Vaginal birth may remain reasonable for many, while planned caesarean may be considered in selected cases.

Questions worth discussing at your consultation

What grade of tear occurred and how was it repaired?
When should pelvic-floor physiotherapy begin?
Which bowel symptoms require specialist review?
How will this affect planning for another birth?

When to seek urgent careSeek urgent review for fever, worsening wound pain, foul discharge, opening of the wound, inability to control stool, severe constipation with pain or heavy bleeding.

Medical note: This page is educational and is structured to support a specialist consultation. Diagnosis, investigations and treatment must be individualised. It has not been presented as a substitute for an examination or emergency assessment.