Blood flow velocities in the cerebral arteries and descending aorta in small-for-dates infants.

Resistive indices (RI) in the anterior cerebral artery (ACA), basilar artery (BA), middle cerebral artery (MCA) and descending aorta (DA) were obtained in 15 small-for-dates (SFD) infants who were, growth retarded because of maternal pregnancy-induced hypertension and in 20 appropriate-for-dates (AFD) infants matched for gestational age between 24 h and 48 h after birth. The RIs in the MCA, ACA and BA were significantly lower, while the RI in the DA was significantly higher, in the SFD infants than in the AFD infants. These changes in RIs in the SFD infants might be similar to the "brain sparing" effect as reported in growth-retarded fetuses.