Coexistent hydatidiform mole and live fetus in the second trimester: an ultrasound study

The authors describe 4 cases of hydatidiform mole with a live fetus delivered between 20 and 22 weeks gestation. The ultrasound and clinical findings and the pathological classification are discussed. In 2 patients the mole completely replaced a separate placenta in a multiple gestation; in the other 2, the mole partially replaced a solitary placenta.