Detection of an adnexal mass during pregnancy has increased during the last decade due to liberal use of sonographic examination during the first trimester. While most are benign or physiologic, the probability of a malignant tumor should always be considered. Deciduosis, a phenomenon related to pregnancy, refers to the presence of decidua outside the uterine cavity, most commonly seen within the pelvis. It is a benign condition, which usually regresses during the postpartum period. However, during pregnancy, this ectopic decidua may enlarge and mimic malignancy.
Endometriosis ; Pregnancy