Chronic ectopic pregnancy: Ultrasonic diagnosis

The classical ultrasonic description of a chronic ectopic pregnancy is a slightly enlarged uterus with uniform internal echoes and no evidence of an intrauterine pregnancy, combined with an extrauterine semicystic mass, gestational sac, or fetal structures. It is our experience that the ultrasonographer more commonly finds a midline pelvic mass containing irregular echo patterns and cystic areas. The mass may also be associated with abdominal or pelvic fluid and obliteration of normal anatomical structures. We wish to emphasize these variations from the classical description with illustrations that demonstrate the differences in the ultrasonic presentation of chronic ectopic pregnancy.