Large rectovaginal fistula due to a cube pessary despite routine follow-up; but what is 'routine'?

Vaginal pessaries are generally considered a safe and effective form of management for pelvic organ prolapse. Serious complications such as rectovaginal fistula can develop with or without regular follow-up. This case report describes the rapid development over a 10-week period of a large rectovaginal fistula in a 75-year-old woman, despite routine follow-up and replacement of her cube pessary. Currently, there is a lack of evidence-based guidelines for pessary care and, in particular, the frequency of pessary replacement. Intervals for pessary replacements vary greatly and are often based on the manufacturer's recommendations. This case highlights the rapidity at which serious complications can develop and also represents the first reported case of a cube pessary-induced rectovaginal fistula.