Age-independent assessment of abnormal fetal growth in the third trimester

This study assessed the use of the sonographic growth rate of a fetus in the third trimester independently of its gestational age as a tool to evaluate adequacy of fetal growth. Ultrasonographic records were reviewed to calculate our third trimester growth rate, and three rates of fetal growth were established. One hundred and thirty-three patients having two third trimester sonographic examinations were then studied, and our average, above average, and below average growth rate zones were found to be excellent predictors for fetal size at birth. The below-average zone identified fetuses who were not clinically suspected of having IUGR but were determined to be SGA at birth.