To the Editor .—Spontaneous renal rupture is a rare complication of pregnancy, but is hazardous to both the mother and the infant. It seems hardly possible to initially diagnose spontaneous renal rupture in a pregnant woman, mainly because it presents the symptoms of acute abdomen, and because the incidence of the disease is rare. We report a case of a pregnant women with spontaneous renal rupture in whom renal arteriography confirmed the diagnosis. Report of a Case .—A 31-year-old pregnant woman, in the third trimester, was admitted to the hospital on June 15, 1986, because of severe left flank pain of sudden onset that was accompanied by shock. When she recovered from the shock by means of multiple infusions, her blood pressure was 134/80 mm Hg, and her heart rate was 90 beats per minute. Fetal heart sounds were not audible. Marked tenderness was found in the lower left abdominal