Decidualized Ovarian Endometrioma in a Pregnant Woman Mimicking Ovarian Malignancy: Magnetic Resonance Imaging and Ultrasonographic Findings

Decidualized ovarian endometrioma is a rare phenomenon in pregnancy, which can mimic ovarian malignancy in imaging and often poses a diagnostic challenge. We report a case of a large ruptured decidualized ovarian endometrioma in a 15 weeks gestation patient, and we will describe the imaging characteristics (ultrasonography and MR imaging findings) and the histopathological findings (macro- and microscopically).