Purpose: One of the most common causes of faecal incontinence in women is a third or fourth degree obstetric anal sphincter injuries (OASI). Endoanal ultrasound and manometry are commonly used to assess anal sphincter defects and function after childbirth. However, its role in asymptomatic patients is less well defined. In addition, the recommended mode of delivery post OASI injury is variable in the absence of clinical symptoms of incontinence. Methodology: This is a cross-sectional audit of all ultrasound and manometry for women who had a third or fourth degree tear between 1/1/2022 and 31/12/2024 and attended the perineal clinic at Royal Prince Alfred Hospital. Results: Ultrasound and manometry findings were discordant and unpredictable in those who developed a third or fourth degree tear after childbirth. Bowel function and continence scores provided better correlation to ultrasound and manometry findings than the incident injury. Conclusion: Whilst third and fourth degree OASI were higher risk for incontinence, post injury ultrasound and manometry findings did not provide a direct correlation with bowel function.