[Observation on ultrasonic placental grading of the toxemia and chronic hypertension of pregnancy].
D005260:Female; D005317:Fetal Growth Retardation / Q000209:etiology; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D010920:Placenta / Q000473:pathology*; D011225:Pre-Eclampsia / Q000503:physiopathology*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000503:physiopathology*; D014463:Ultrasonography