Obstetric trauma is the most common cause of rectovaginal fistula (RVF), typically resulting from prolonged labor, perineal tears, or instrumental delivery. These injuries lead to necrosis and subsequent fistula formation between the rectum and vagina. The fistula causes fecal contamination of the vagina and significant morbidity. Surgical repair often requires careful debridement of necrotic tissue and layered closure to restore the integrity of both the rectal and vaginal walls. Early recognition and prevention of obstetric injury are critical in reducing RVF incidence.

Reference: Principles of Surgery, Schwartz, 11th Edition.