Intraperitoneal foreign body as a cause of acute abdomen in pregnancy.

Although surgical textbooks commonly include foreign bodies in the differential diagnosis of acute abdomen, this cause of abdominal pain has not been reported in the obstetric literature. A 35-year-old woman presented at 24 weeks' gestation with right lower quadrant pain and peritoneal signs. The only abnormal finding at exploratory laparotomy was a free-floating intraperitoneal foreign body, presumably left inadvertently during prior surgery. The differential diagnosis of acute abdomen in pregnancy should include intraperitoneal foreign body in any woman with a history of previous abdominal surgery.