The echoic pseudogestational sac of ectopic pregnancy simulating early intrauterine pregnancy.

The sonographic features of ectopic pregnancy have been well documented. When an early intrauterine pregnancy is identified or an obvious extrauterine sac is visualized, diagnosis is not a problem; but often a sac is seen within the uterus that may contain a well-defined rind and even internal echoes simulating an early fetal pole. This has been mistaken for an early intrauterine pregnancy. In this review, four patients with pseudogestational sacs had internal echoes within the sac, and two of them ultimately underwent dilatation and curettage, which revealed blood clots. This supports the assertion that fetal cardiac activity and/or fetal motion should be demonstrated within a fetal pole before the diagnosis of ectopic pregnancy is excluded.