Comparison of dynamic image and pulsed Doppler ultrasonography for the diagnosis of the small-for-gestational-age fetus.

Abstract

Because poor fetal growth is a significant cause of perinatal morbidity and mortality, a prospective study was undertaken to evaluate the ability of real-time ultrasonography and Doppler velocimetry to detect the small-for-gestational-age fetus. A prospective study of 136 women at risk for fetal growth abnormalities was conducted. Patients were delivered within 3 weeks and had live-born, nonanomalous, singleton infants. The relative estimated fetal weight (estimated fetal weight divided by the median birth weight for gestational age) and the systolic/diastolic ratio were measured and compared with receiver-operator characteristic curves. In this method the area under the curve is the index of performance. Forty-six infants were small for gestational age. Although both relative estimated fetal weight (area under the curve = 0.923) and systolic/diastolic ratio (area under the curve = 0.837) were significantly associated with the small for gestational age fetus, the former was more strongly correlated, p = 0.021. Relative estimated weight is more sensitive and specific and should be the preferred parameter when gestational age is known.