Coexistent endometriomas in pregnancy: Sonographic appearance

Sonography has proven to be an invaluable tool in the diagnosis of normal and pathological processes occurring during pregnancy. One of the commonest reasons for performing diagnostic ultrasound is to examine patients who are large for dates, which is often secondary to inaccurate patient dating of the pregnancy. Ultrasound may be useful in diagnosing other causes of patients being large for dates, such as twin pregnancy, polyhydramnios, molar pregnancy, or a concomitant pelvic mass. One of the rare concomitant pelvic masses occurring during pregnancy that should be considered in a patient large for dates is an endometrioma. No sonographic cases of an endometrioma occurring during pregnancy have been presented in the literature. Such a case in a twin pregnancy is presented here, along with a review of endometriosis and its sonographic findings.