Intrauterine growth retardation (IUGR) is associated with increased fetal and neonatal morbidity and mortality. In a previous study from the authors' laboratory, it was found that a grade 3 placenta on ultrasound examination was helpful in diagnosing the growth-retarded fetus. The present study was designed to evaluate whether this technique would be applicable in clinical practice. In the present study of 191 pregnancies, positive sonographic screening, defined as a fetal biparietal diameter of 87 mm or less, and a grade 3 placenta were found to detect 59% of all growth-retarded fetuses; in addition, half of the identifications of growth-retarded fetuses were correct. Overall risk for IUGR was increased 8.5 times in the presence of a positive sonographic screen--3.5 times for the preterm (less than 38 weeks' gestation) fetus and 18 times for the term fetus. This suggests that information readily available from real-time ultrasound examination--placental maturity grading and biparietal diameter--can improve the detection of IUGR.