An unusual case of diverticulitis complicating pregnancy at 33 weeks' gestation.

A 38-year-old para 2 presented with the gradual onset of nausea vomiting and increasing left lower quadrant pain, at 33 weeks' gestation. She was known to have uterine leiomyomas, with ultrasonography depicting an 8-cm intramural fundal leiomyoma. In addition a left lateral nondiscrete 10 x 8-cm mass was depicted at the point of maximum tenderness. Magnetic resonance imaging (MRI) demonstrated diverticulosis of the descending and sigmoid colon. The patient remained afebrile and received repeated doses of intramuscular analgesics and was cleared by the surgical consultant, only to be readmitted with similar symptomatology 24 hours later. Subsequently, following repeat discharge she delivered at 34 weeks' gestation, and developed a small bowel obstruction during the immediate postpartum course. With the continued finding of a left lower abdominal mass and computed tomography findings suggestive of perforated sigmoid diverticulitis and resulting small bowel obstruction, laparotomy was performed. Multiple adhesions and phlegmon sequelae of chronic perforation of the sigmoid were confirmed, and a diverting descending colostomy and Hartman's procedure were performed. We present unusual MRI findings of diverticulitis in the third-trimester and review the literature pertaining to this unusual complication of pregnancy.