What are the causes of recto-vaginal fistulae?

Q: Is a recto-vaginal fistulae common after a forceps delivery?

A:The most common cause of a recto-vaginal fistula is obstetric injury, followed by radiation injury, inflammatory bowel disease (most often Crohn’s disease), operative trauma, infectious causes, and neoplasm. Perineal lacerations are more common in primigravidas, in precipitous births, or when forceps or vacuum extraction is used.