Obstetric anal sphincter injuries: strategies for prevention, diagnosis, and management.

Obstetric anal sphincter injuries (OASIS) are one of the most common causes of anal incontinence (AI) in women of reproductive age and can have a significant impact on quality of life. However, many women do not report symptoms to their physicians because of embarrassment and shame. Therefore, prevention and diagnosis of the tear is essential. Diagnostic strategies have evolved considerably in recent years, with an increase in prevalence of OASIS as a consequence. The use of 3D endoanal (3D-EAUS) and 4D transperineal ultrasound (4D-TPUS), in addition to standard clinical examination have enhanced the detection of OASIS. Once identified, adequate repair by a skilled practitioner and optimal postpartum management should be ensured in order to reduce the risk of anal incontinence. This review presents the available evidence on strategies for prevention, diagnosis, and management of OASIS.