Sonographic diagnosis of a pregnancy with a diffuse hydatidiform mole and coexistent 46,XX fetus: a case report.

Placental molar change with a coexistent live fetus is an unusual entity, particularly when diagnosed in the second trimester of pregnancy. In this case report, the sonographic findings of an abnormally enlarged, diffuse molar placenta with a normal living fetus in the second trimester prompted karyotype analysis. Although triploidy was anticipated, a normal 46,XX chromosomal complement was identified. Histopathology of the placenta after delivery confirmed the rare syndrome of diploid partial mole. Antenatal management of this unusual pregnancy complication is addressed.