Molar pregnancy: early diagnosis by ultrasound.

This report reviews four cases with vaginal bleeding and early ultrasound diagnosis of abnormal pregnancy before nine weeks gestation, who were followed by serial ultrasound examinations and subsequently diagnosed as hydatidiform mole. The findings support the view that hydatidiform mole may arise from a blighted ovum. It is concluded that vaginal bleeding in the first trimester should be investigated by diagnostic ultrasound, and the pregnancy by terminated if an abnormal development has been confirmed.