Perineal hernia because of retroflexion of the urinary bladder in a rottweiler bitch during pregnancy

A young pregnant rottweiler bitch was presented with a large mass of tissue protruding through the vulvar lips. Foetal death was diagnosed on ultrasonography, and ovariohysterectomy was performed, at which time the bladder was observed to be dislocated caudally into the pelvic cavity under the vagina. The bladder was manually repositioned during surgery. One week later, the bitch was healthy with no evidence of dysuria, stranguria or urinary incontinence. Two months later, the owner reported that the bitch was clinically normal with no recurrence of the retroflexion. To the authors' knowledge, this is the first reported case of retroflexion of the urinary bladder during pregnancy.