{Reference Type}: Case Reports {Title}: Deciduosis of the appendix: a rare cause of acute abdomen during pregnancy (a case report). {Author}: Smits L;Bockstal MV;Frezin J; {Journal}: Pan Afr Med J {Volume}: 37 {Issue}: 0 {Year}: 2020 暂无{DOI}: 10.11604/pamj.2020.37.316.26728 {Abstract}: Appendectomy is the most common non-obstetric surgical intervention in pregnant patients. In rare cases, deciduosis can develop during pregnancy in the appendix and cause inflammation through appendiceal occlusion by ectopic decidua tissue. We report a 28-year-old woman at 32 weeks of pregnancy, who presented at the emergency room with the diagnosis of an acute appendicitis. After successful appendectomy and histopathological examination of the appendectomy specimen, a diagnosis of appendiceal deciduosis with acute appendicitis was established. Here, we discuss the origin of appendiceal deciduosis, as well as its clinical and histopathological presentation.