Sonographic diagnosis of complete mole and co-existent fetus: case report.

Coexistence of a complete mole and a normal fetus is a rare event. First trimester sonographic appearance of a complete molar pregnancy with a coexistent fetus and its sonographic differentiation from entities that may simulate a hydatidiform mole in its early stages is discussed. The reported case is one of a 19 y/o woman G2P1001 who was hospitalized several times for abnormal uterine bleeding. Characteristically, the sonographic appearance of a hydatidiform mole is of a moderately echogenic, multicystic intrauterine soft tissue mass. In this particular case, the initial presentation was that of a complex intrauterine fundal mass adjacent to a normal embryo, thus molar pregnancy was considered as part of the differential diagnosis. Doppler evaluation of the echogenic intrauterine mass has been proposed in addition to HCG evaluation, in order to differentiate from trophoblastic and non-trophoblastic disease. In differentiating between a partial and a complete molar pregnancy it is most important to realize that the diagnosis is difficult by ultrasonography because both present with the same multicystic or vesicular pattern. However, if there is a coexistent fetus such as in our reported case, the differentiation would be possible on basis of the presence of a sonographically normal placenta separated from the degenerated placenta.