[Acute appendicitis caused by pregnancy-associated ectopic decidua. Case report and discussion of pathogenesis]

The occurrence of pregnancy-associated ectopic decidua is a well-documented phenomenon. It has been observed most often in the ovaries, uterus, and cervix. An extragenital localization is less frequent and usually an asymptomatic, incidental finding. We report on a 32-year-old woman in her third trimester of pregnancy who developed acute appendicitis caused by ectopic decidua. This case illustrates a rare differential diagnosis of acute appendicitis and discusses the pathogenesis of pregnancy-associated ectopic decidua in such cases.