A 4-year-old Suffolk ewe in the last trimester of gestation was referred to Veterinary Teaching Hospital with history of an acute, progressive, bilateral abdominal distention. After 10 days of hospitalization, the animal underwent a cesarean section in the paramammary region that revealed a grossly distended, thin-walled, fluid-filled uterus with 18 liters of allantoic fluid and 2 lambs. Two days after surgery, the ewe was alert, able to stand and had normal appetite. Abdominal distention did not recur after surgery and neither retention of fetal membranes nor septic metritis signs were observed. Ten days after surgery the animal was discharged to the farm. Rebreeding was discouraged in this case.