Purpose: Doppler flow parameters of fetal umbilical artery (UA) and middle cerebral artery (MCA) have been widely used for fetal growth restriction (FGR), but their diagnostic efficacy remains contentious. The purpose of this study is to clarify the superiority of cerebroplacental ratio (CPR) and umbilicocerebral ratio (UCR) in terms of their correlation and predictive accuracy in diagnosing FGR.