A rectovaginal fistula is an abnormal tunnel between the rectum and the vagina. Stool or gas leaks through this side door, so symptoms are hard to miss and tough to live with.

Passing gas or stool from the vagina is the hallmark. You feel bubbles or see brown streaks on your panties that have nothing to do with your period.

Foul vaginal odor persists. A constant stool smell lingers even after bathing and changing underwear.

Recurrent vaginal or urinary infections follow. Bacteria from the bowel irritate the vagina and bladder, causing burning, itching, or discharge.

Staining shows up daily. Panty-liners are soaked with brown or yellow fluid minutes after a bowel movement.

Pain is usually mild but spikes during sex or when the area becomes inflamed.

Late signs include a hard lump or red streaks on the skin—an alarm that the infection is spreading.